UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

___________________________________

FORM 10-K



x	ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, ~~2012~~2013



o	TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Commission File Number 001-33213

___________________________________

AFFYMAX, INC.

(Exact name of registrant as specified in its charter)

___________________________________



Delaware		77-0579396
(State or other jurisdiction of incorporation or organization)		(I.R.S. Employer Identification Number)

~~4001 Miranda~~19200 ~~Avenue~~Stevens Creek Blvd. Suite 240

~~Palo Alto~~Cupertino, CA ~~94304~~95014

(650) 812-8700

(Address, including zip code, and telephone number, including

area code, of registrant’s principal executive offices)

Securities registered pursuant to Section 12(b) of the Act:

Title of Each Class		Name of Each Exchange on Which Registered
Common stock, par value $0.001 per share		Over The ~~NASDAQ~~Counter ~~Stock Market LLC~~(OTC)

Securities registered pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes o No ý

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes o No ý

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes x No o

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes x No o

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K ý

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer o Accelerated filer xo Non-accelerated filer ox(Do not check if a smaller reporting company) Smaller reporting company o

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o No x

The aggregate market value of the registrant's common stock, $0.001 par value, held by non-affiliates of the registrant as of June 30, ~~2012~~2013 was $~~463~~38,~~771~~370,~~551~~661 (based upon the closing sales price of such stock as reported on the ~~Nasdaq~~Over-the-Counter ~~Global~~electronic ~~Select~~market ~~Market~~ on such date). Excludes an aggregate of ~~139~~237,~~248~~026 shares of the registrant's common stock held by officers, directors and affiliated stockholders. For purposes of determining whether a stockholder was an affiliate of the registrant at June 30, ~~2012~~2013, the registrant has assumed that a stockholder was an affiliate of the registrant at June 30, ~~2012~~2013 if such stockholder (i) beneficially owned 10% or more of the registrant's common stock and/or (ii) was affiliated with an executive officer or director of the registrant at June 30, ~~2012~~2013. Exclusion of such shares should not be construed to indicate that any such person possesses the power, direct or indirect, to direct or cause the direction of the management or policies of the registrant or that such person is controlled by or under common control with the registrant.

As of February 28, ~~2013~~2014, 37,~~400~~490,~~135~~095 shares of the registrant’s common stock, $0.001 par value, were outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Specified portions of the Proxy Statement for the ~~2013~~2014Annual ~~Annual~~ Meeting of Stockholders (the "Proxy Statement"), to be filed with the Securities and Exchange Commission within 120 days of the end of the fiscal year ended December 31, ~~2012~~2013, are incorporated by reference into Part III of this Annual Report on Form 10-K. Except with respect to information specifically incorporated by reference into this Annual Report on Form 10-K, the Proxy Statement is not deemed to be filed as part hereof.

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AFFYMAX, INC

TABLE OF CONTENTS

		Page
	PART I.
Item 1.	Business	3
Item 1A.	Risk Factors	1211
Item 1B.	Unresolved Staff Comments	2927
Item 2.	Properties	3027
Item 3.	Legal Proceedings	3028
Item 4.	Mine Safety Disclosures	3029
	PART II.
Item 5.	Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities	3130
Item 6.	Selected Financial Data	3231
Item 7.	Management's Discussion and Analysis of Financial Condition and Results of Operations	3433
Item 7A.	Quantitative and Qualitative Disclosure About Market Risk	5244
Item 8.	Financial Statements and Supplementary Data	5345
Item 9.	Changes in and Disagreements with Accountants on Accounting and Financial Disclosure	8577
Item 9A.	Controls and Procedures	8577
Item 9B.	Other Information	8778
	PART III.
Item 10.	Directors, Executive Officers and Corporate Governance	8879
Item 11.	Executive Compensation	8879
Item 12.	Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters	8879
Item 13.	Certain Relationships and Related Transactions and Director Independence	8879
Item 14.	Principal Accountant Fees and Services	8879
	PART IV.
Item 15.	Exhibits and Financial Statement Schedules	8980

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This Annual Report on Form 10-K contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, which are subject to the “safe harbor” created by those sections. Forward-looking statements are based on our management's beliefs and assumptions and on information currently available to our management. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “could,” “would,” “expect,” “intend,” “plan,” “anticipate,” “believe,” “estimate,” “project,” “predict,” “potential” and similar expressions intended to identify forward-looking statements. These forward-looking statements include, but are not limited to, statements regarding our ability to continue our business, operations, and investigation following the recall of ~~OMONTYS,~~OMONTYSand the continuation and success of our collaboration with Takeda Pharmaceutical Company Limited~~, and the timing, design and results of our clinical trials and drug development program~~. These statements involve known and unknown risks, uncertainties and other factors, which may cause our actual results, performance, timing or achievements to be materially different from any future results, performance, timing or achievements expressed or implied by the forward-looking statements. We discuss many of these risks, uncertainties and other factors in this Annual Report on Form 10-K under Item 1A “Risk Factors.” Given these risks, uncertainties and other factors, you should not place undue reliance on these forward-looking statements. Also, these forward-looking statements represent our estimates and assumptions only as of the date of this filing. You should read this Annual Report on Form 10-K completely and with the understanding that our actual future results may be materially different from what we expect. We hereby qualify our forward-looking statements by these cautionary statements. Except as required by law, we assume no obligation to update these forward-looking statements publicly, or to update the reasons actual results could differ materially from those anticipated in these forward-looking statements, even if new information becomes available in the future.

PART I.

Item 1. Business.

Overview

We are a biopharmaceutical company ~~committed~~in ~~to discovering, developing and delivering innovative therapies that improve~~ the ~~lives~~process of ~~patients~~restructuring ~~with kidney disease and other serious and often life-threatening illnesses~~operations. In March 2012, the U.S. Food and Drug Administration, or FDA, approved ~~our~~the Company’s first and only product, OMONTYS® (peginesatide) Injection for the treatment of anemia due to chronic kidney disease in adult patients on dialysis. OMONTYS is a synthetic, peptide-based erythropoiesis stimulating agent, or ESA, designed to stimulate production of red blood cells~~. Our~~ ~~product~~and ishas been the only once-monthly ESA ~~that has been~~ available to the adult dialysis patient population in the U.S. In We ~~2012, we~~ co-commercialized OMONTYS ~~in the U.S.~~ with our collaboration partner, Takeda Pharmaceutical Company Limited, or Takeda during 2012 until February 2013, when we and Takeda announced a nationwide voluntary recall of OMONTYS as a result of safety concerns. Effective April 1, 2013, we entered into an amendment of our collaboration with Takeda pursuant to which Takeda assumed full responsibility for OMONTYS, including responsibility for the ~~largest~~ongoing ~~pharmaceutical~~recall ~~company~~and investigation with the FDA, and we granted them an exclusive license to OMONTYS in ~~Japan.~~consideration for potential royalties and milestones.

InRestructuring February 2013 and in consultation with the FDA, we and Takeda voluntarily recalled OMONTYS nationwide from the market as a result of post-marketing reports regarding serious hypersensitivity reactions, including anaphylaxis, which can be life-threatening or fatal. In connection with the recall, we and Takeda suspended all promotional and marketing activities for OMONTYS. While we continue to investigate the potential cause of the safety concerns at this time, we face significant challenges to our business. We are unable to estimate the scope or timelines associated with the investigation, which may be costly and time-consuming, and with our limited funds and resources, we may not be able to complete the investigation or ever identify the causes of the safety concerns.

In March 2013, we ~~undertook~~implemented plans to ~~reorganize~~restructure our operations in order to reduce operating costs and focus on the OMONTYS safety and other related FDA issues associated with the recall of the product. As Inof December 31, 2013, in addition to transitioning many of the ongoing activities to our collaborator, Takeda, ~~our~~we ~~plans~~completed ~~include~~ a ~~significant~~ reduction in force of ~~approximately~~almost ~~230~~all ~~employees (75% of~~ our ~~workforce)~~personnel, including all of our commercial and medical affairs field forces as well as other employees throughout the organization. We ~~expect~~have torecorded ~~incur between~~ $816.01 million ~~and $10.0 million~~ in restructuring charges related to the workforce reduction during the ~~first~~year ~~quarter~~ending ofDecember 31, 2013. As a result of this restructuring and the recall, we ~~may~~ also ~~incur~~recorded ~~additional~~impairment charges ~~depending~~of on$4.4 ~~further~~million ~~review~~with ~~and~~respect ~~additional~~to ~~reductions~~our inproperty ~~operations~~and equipment and ~~may~~intangible ~~also~~assets ~~experience~~related ~~impairment~~to ~~changes~~our ~~with~~license ~~respect~~from toJanssen ~~our~~Biotech, ~~property~~Inc. ~~and~~(a ~~equipment~~subsidiary of Johnson & Johnson) and ~~long~~certain ~~lived~~of ~~assets~~its affiliated companies, collectively referred to as Janssen, in the ~~first~~year ~~quarter~~ended ofDecember 31, 2013.

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~~operations even in the near term, however, we may not be successful. We are particularly dependent on~~ Takeda's willingness to continue the collaboration in a modified form that reduces our operating expenses and responsibilities under the collaboration, but we may also be required to reduce our share of OMONTYS profits if and when the product may be re-introduced in the future. Even if Takeda is willing to assume additional responsibilities under the collaboration, including the conduct of most or all of the ongoing investigation, the loss of critical personnel and functions means that we may not be able to maintain our operations, support the New Drug Application or NDA, continue as a going concern or ever re-introduce OMONTYS. Amendment

InEffective ~~view~~April of1, ~~our~~2013, ~~limited~~we ~~resources~~and Takeda, collectively the Parties, entered into the Fourth Amendment, or the Amendment, to the February 13, 2006 and ~~funds~~June 27, we2006 ~~plan~~Collaboration and License Agreements to ~~explore~~amend ~~various~~and ~~strategic~~restate ~~alternatives~~the ongoing respective roles and responsibilities and related commitments and financial terms between the Parties, including athe ~~sale~~termination of the ~~company~~Collaboration orand ~~its~~License ~~assets~~Agreement ordated as of February 13, 2006, under which we had granted Takeda a ~~corporate~~certain ~~merger~~right and license for the development and commercialization in Japan of OMONTYS, as amended by the First Amendment, dated April 1, 2007, the Second Amendment, dated January 1, 2008 and the Third Amendment, dated November 7, 2011, as well as the related manufacturing supply, safety, quality and co-promotion agreements between the parties. We The ~~are~~Amendment ~~considering~~revised ~~all~~the ~~possible~~economics ~~alternatives~~from a profit-sharing arrangement to a milestone and royalty-based compensation structure to us effective as of April 1, ~~including~~2013. This ~~further~~Amendment was part of our restructuring ~~activities~~efforts resulting from the voluntary recall announced on February 23, ~~wind-down~~2013 related to OMONTYS, the suspension of ~~operations~~U.S. ormarketing ~~even~~and ~~bankruptcy~~promotional ~~proceedings~~activities, and the ongoing investigation with the FDA. The arrangement with Takeda including the Amendment is referred to as the Arrangement.

IfThe weAmendment ~~and~~effectuated ~~Takeda~~a ~~are~~transfer ~~unable to rapidly identify and rectify the causes~~ of ~~the~~regulatory ~~safety concerns to the satisfaction of the FDA~~responsibilities, ~~which~~including ~~is highly uncertain, OMONTYS may be permanently withdrawn from~~ the ~~market. The recall of~~ OMONTYS ~~has~~New ~~severely~~Drug ~~harmed~~Application, ~~our~~or ~~business~~NDA, ~~financial condition~~ and ~~prospects~~all asmanufacturing, ~~a going concern. The recall has also limited our access to funds~~ and ~~the~~development ~~resources~~responsibilities ~~that~~from ~~may~~us ~~be required in order~~ to ~~address the safety concerns~~Takeda. As Takeda received a ~~result~~worldwide, weexclusive ~~may~~royalty-bearing belicense ~~unable~~under ~~to continue~~ our ~~operations. In order to reintroduce OMONTYS, we would have to complete our ongoing thorough investigation, identify the causes of the safety concerns~~ and ~~provide~~joint aTakeda-Affymax ~~suitable~~patents ~~plan~~ to ~~the FDA for approval. Accordingly~~develop, ~~there~~manufacture ~~can be no assurance that we can address the safety concerns~~ and ~~meet~~commercialize ~~the requirements of the FDA for reintroduction. Moreover, even if~~ OMONTYS ~~could be reintroduced, the commercial prospects for this product may be permanently diminished and the product may no longer be commercially viable~~.

WeAs ~~were~~a ~~incorporated~~result inof ~~Delaware~~the inAmendment, ~~July~~Takeda ~~2001~~assumed ~~under~~full ~~the~~responsibility ~~name~~for ~~Affymax~~OMONTYS, ~~Inc.~~ ~~The~~including ~~address~~the ongoing recall and investigation of ~~our~~OMONTYS ~~principal~~as ~~executive~~well ~~office~~as any subsequent decisions as to whether the product may be subject to reintroduction if Takeda is ~~4001~~able ~~Miranda~~to ~~Avenue,~~complete ~~Palo~~the ~~Alto~~investigation and address the safety concerns to the satisfaction of the FDA. If Takeda decides to reintroduce OMONTYS, ~~California~~which ~~94304~~is highly uncertain, we are eligible to receive royalties and ~~our~~(i) ~~telephone~~potential ~~number~~commercial milestone payments totaling up to $180.0 million which consists of the following: (a) $10.0 million is payable upon the first commercial sale after reintroduction of OMONTYS in the U.S.; (~~650~~b) ~~812~~ $10.0 million and another $10.0 million relates to U.S. sales-~~8700~~based milestones, and (c) $150.0 ~~Our~~million ~~website~~relates ~~address~~to issales-based ~~www~~milestones in amounts as previously disclosed outside of the U.~~affymax~~S.~~com~~ but now including Japan as a result of the Amendment and (ii) a potential development milestone payment of $5.0 million payable either upon regulatory approval in the E.U. or Japan. WeThe doroyalties ~~not~~are ~~incorporate~~tiered in the ~~information~~range onof ~~our~~13% ~~website~~to ~~into~~17% ~~this~~with ~~Annual~~respect ~~Report~~to onnet ~~Form 10-K,~~sales ~~and~~in ~~you~~the ~~should~~U.S. ~~not~~and ~~consider~~in itthe ~~part~~range of ~~this~~13% ~~Annual~~to ~~Report~~24% depending on ~~Form 10-K~~the level of net sales by Takeda worldwide outside of the U.S.

WeIn ~~have~~2012, ~~registrations~~we orco-commercialized ~~pending~~OMONTYS ~~applications~~with ~~for~~Takeda. The commercial launch of the ~~trademarks~~product ~~“Affymax”,~~occurred ~~“Affymax~~in ~~and~~April ~~logo,”~~2012. To “commercialize OMONTYS,” ~~and~~we ~~"OMONTYS~~established commercial and ~~logo"~~medical inaffairs ~~the~~infrastructures Uin 2012.S. The functions of our commercial and ~~select~~medical ~~foreign~~affairs ~~countries~~infrastructures included marketing and sales, medical education, coverage and reimbursement and account management.

In 2012 and in 2013 up until the recall of OMONTYS, we marketed our product primarily to dialysis organizations. Associated costs are included in selling, general and administrative costs or SG&A in our accompanying financial statements.

In 2012 and in 2013 up until the recall of OMONTYS, Takeda was responsible for account management, pricing and contracting. Specifically, Takeda had sole responsibility for invoicing and collection of receivables with regard to sales of OMONTYS. Takeda also had the rights and responsibility for establishing and modifying terms and conditions with customers with respect to the sale of OMONTYS in the U.S., including pricing discounts available to third-party payers, price adjustments and other allowable discounts and allowances. Both parties also had shared responsibilities such as joint marketing activities, business analytics and account management allocated by customer segments.

Prior to the Amendment, outside of the U.S., Takeda held an exclusive license to develop and commercialize OMONTYS and has primary responsibility for filing regulatory submissions and obtaining product approvals in those territories.

We were incorporated in Delaware in July 2001 under the name Affymax, Inc. The address of our principal executive office is 19200 Stevens Creek Boulevard, Suite 240, Cupertino, California 95014, and our telephone number is (650) 812-8700. Our website address is www.affymax.com. We do not incorporate the information on our website into this Annual Report on Form 10-K, and you should not consider it part of this Annual Report on Form 10-K.

Our Product: OMONTYS

In March 2012, the FDA approved our first product, OMONTYS, for the treatment of anemia due to chronic kidney disease in adult patients on dialysis. ~~Although~~In ~~the regulatory approval has not been permanently withdrawn, in~~ February 2013, the product ~~has~~was ~~been~~ recalled nationwide and all promotion and marketing activities have been suspended.

Anemia Background

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Anemia is a serious condition in which blood is deficient in red blood cells and hemoglobin. Red blood cells are normally formed in the circulating blood from precursor cells which are initially present primarily in the bone marrow. These cells are stimulated to divide and differentiate and are mobilized into circulation by erythropoietin, or EPO, a hormonal factor produced by the kidney. EPO acts by binding to and activating the EPO receptor on precursor cells. The activation of the EPO receptor stimulates the proliferation and maturation of the precursor cells to form red blood cells that contain hemoglobin. Hemoglobin is an iron-containing protein in red blood cells that functions primarily in the transport of oxygen to, and carbon dioxide from, the tissues of the body.

Anemia generally exists in men when the hemoglobin level in blood, which is a measure of red blood cells, is less than 12 g/dL, or the hematocrit, which is a ratio of the volume packed red blood cells to the volume of whole blood, is less than 36%, and in women when hemoglobin is less than 11 g/dL or hematocrit is less than 33%. Anemia is common in patients with chronic kidney disease, cancer, heart failure, inflammatory diseases and other critical illnesses, as well as in the elderly. If left untreated, anemia may lead to chronic fatigue or increase the risk of other diseases or death. Currently, ESAs are used to treat chemotherapy-induced anemia in cancer patients and to treat anemia due to chronic kidney disease in patients on dialysis and not on dialysis.

Anemia and Chronic Kidney Disease

One of the most common forms of chronic anemia occurs in patients with chronic kidney failure. According to the Center for Disease Control, chronic kidney failure affects over 20 million adults in the U.S. As kidney function deteriorates due to the underlying disease, the ability of the kidney to produce adequate EPO is impaired, resulting in decreased production of new red blood cells and anemia.

Over time, chronic kidney disease usually progresses to irreversible end-stage renal disease, the most severe stage of the disease. End-stage renal disease patients require either lifetime dependence on renal dialysis, a medical procedure in which blood is cleansed of impurities, or a kidney transplant. Patients with end-stage renal disease are nearly always moderately to severely anemic unless treated with an ESA. According to U.S. Renal Data System, there were approximately 415,000 end-stage renal disease patients on dialysis in the U.S. in 2010.

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blood is cleansed of impurities, or a kidney transplant. Patients with end-stage renal disease are nearly always moderately to severely anemic unless treated with an ESA. According to U.S. Renal Data System, there were approximately 415,000 end-stage renal disease patients on dialysis in the U.S. in 2010.

Anemia Therapy and Limitations

Prior to the introduction of OMONTYS, all ESAs were recombinant EPO, or rEPO. Forms of rEPO variants have been used successfully to manage the anemia of dialysis, non-dialysis and cancer patients. rEPOs are similar, but not necessarily identical, to a patient's naturally occurring EPO. Differences exist among rEPOs with regard to composition and structure. As a result, differences also exist among rEPOs with regard to frequency of dosing, duration of effect and rate of rise in hemoglobin.

Since its initial U.S. market introduction in 1989, rEPO has revolutionized the treatment of patients with anemia resulting from chronic diseases. Two current ESAs, epoetin alfa and epoetin beta, are biologically engineered hormones produced in mammalian cells by recombinant DNA technology. Both are relatively short-acting forms of rEPO that typically require frequent dosing, one to three times per week or up to every two weeks, to obtain a sustained correction of anemia in chronic kidney disease patients on dialysis.

OMONTYS Profile

Less Frequent Dosing. OMONTYS is a synthetic peptide-based ESA designed for less frequent dosing compared to other ESAs available to treat dialysis patients in the U.S. Peptides are composed of amino acids, commonly known as the building blocks of proteins. Typically, a peptide is composed of fewer than 50 amino acids, while a protein contains from 50 to well over 5,000 amino acids. Peptide-based therapeutics may display certain advantages compared to recombinant proteins, including simplicity and low cost of manufacture. In the past, development of peptide-based drug candidates was often slowed by low potency. A second problem historically associated with peptide-based drugs has been a requirement of frequent dosing in vivo. More recently, however, it has been possible to develop peptide-based drugs with potencies nearly equivalent to recombinant proteins and with less frequent dosing requirements. Through the use of our technology, OMONTYS requires less frequent dosing than other ESAs in the U.S. for dialysis patients. OMONTYS is designed to be dosed once every four weeks, compared to recombinant products sold in the U.S. that are predominately dosed either one to three times per week or up to every two weeks in the dialysis setting.

Intravenous or Subcutaneous Administration. Our clinical trials to date have shown similar positive effects on red blood cell formation when OMONTYS is given at comparable doses either intravenously or subcutaneously. These results suggest that OMONTYS may be similarly effective in humans when administered by either route. We believe it may be easier to use OMONTYS than some forms of rEPO, which often have different clinical effects when given subcutaneously versus intravenously.

Room Temperature Storage. Based on the product label, OMONTYS can be stored at room temperature in the hands of the health care providers for limited durations after refrigerated distribution. Other ESAs in the U.S. require cold storage conditions throughout the distribution and storage process until administration to patients.

OMONTYS Voluntary Recall

In February 2013 and in consultation with the FDA, we and Takeda voluntarily recalled OMONTYS nationwide from the market as a result of post-marketing reports regarding serious hypersensitivity reactions, including anaphylaxis, which can be life-threatening or fatal. In connection with the recall, we and Takeda suspended all promotional and marketing activities for OMONTYS.

WeEffective ~~and~~April ~~Takeda~~1, ~~are~~2013, ~~actively investigating these events. If~~ we ~~are~~entered ~~able~~into toan ~~identify~~amendment ~~and~~of ~~address~~our ~~the~~collaboration ~~underlying cause, which is highly uncertain, we will work~~ with Takeda ~~and~~pursuant ~~the FDA~~ to ~~determine~~which ~~the~~Takeda ~~appropriate~~assumed ~~next~~full ~~steps~~responsibility ~~and direction~~ for ~~the product. During this period~~OMONTYS, weincluding ~~have~~responsibility ~~undertaken~~for ~~efforts to suspend or terminate our existing third party arrangements relating to~~ the ~~manufacture~~ongoing ~~and~~recall ~~commercialization of OMONTYS,~~ and ~~depending~~investigation onwith the ~~timing~~FDA, and ~~results of the investigation,~~ we ~~may~~granted ~~not~~them bean ~~able~~exclusive license to ~~reintroduce~~ OMONTYS in aconsideration ~~timely~~for ~~manner,~~potential ifroyalties atand ~~all~~milestones.

Manufacturing and Supply

InUntil ~~2012~~the product recall in February 2013, final OMONTYS drug product was manufactured as a buffered aqueous solution for intravenous or subcutaneous administration. Under our collaboration with Takeda, we ~~are~~were responsible, through our contract manufacturing organizations, or CMOs, for the manufacture and supply of all quantities of OMONTYS active pharmaceutical ingredient, or API, to be used in development and commercialization worldwide, and Takeda iswas responsible for final drug product manufacture and control. ~~We have established long-term commercial supply agreements with two CMOs for OMONTYS API.~~

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~~The~~In ~~two~~connection ~~CMOs~~with ~~are~~the ~~responsible~~recall ~~for~~and ~~procurement~~in ofconsultation ~~raw~~with ~~materials~~Takeda, ~~needed~~we ~~for~~have terminated manufacturing ~~the~~activities. Effective ~~product~~April 1, 2013, we entered into an amendment of our collaboration with Takeda pursuant to which Takeda assumed full responsibility for OMONTYS, including responsibility for the ~~exception~~ongoing ofrecall ~~bulk~~and ~~poly~~investigation ~~(ethylene)~~with ~~glycol~~the ~~reagent~~FDA, orand ~~PEG. We~~we ~~have~~granted athem an exclusive license, ~~manufacturing~~to ~~and~~OMONTYS ~~supply~~in ~~agreement~~consideration ~~with~~for ~~Nektar~~potential ~~Therapeutics~~royalties ALand ~~Corporation~~milestones. In addition, orTakeda ~~Nektar,~~assumed ~~who~~full weresponsibility ~~engaged~~for any subsequent decisions as to ~~manufacture~~whether the product may be subject to reintroduction if Takeda is able to complete the investigation and ~~supply~~address the ~~requirements~~safety concerns to the satisfaction of ~~PEG~~the FDA. We provided transition support to Takeda through April 30, 2013. After April 30, 2013 we have no performance obligations under our agreement with Takeda.

In connection with the recall and in consultation with Takeda, we have undertaken efforts to suspend or terminate manufacturing activities to the extent practicable pending consideration of next steps with OMONTYS. If we are successful in identifying the cause of the recent safety concerns and addressing them successfully, we and Takeda will determine the appropriate next steps to take with OMONTYS. Prior to such time, we are undertaking strategies to decrease our ongoing manufacturing costs and commitments, including but not limited to, termination of orders and agreements, which may lead to disputes or in any event, negatively impact our ability to reintroduce OMONTYS. If we are able to reintroduce OMONTYS, we intend to continue to rely on third-party manufacturers to produce API, which may require significant effort and validation of new CMOs.

Takeda is responsible for supply chain and distribution management. Specifically, Takeda has sole responsibility for order processing, handling all returns, and manufacturing and distribution of finished goods inventory with regard to sales of OMONTYS. We are unable to predict and do not have control over the decisions of Takeda on these activities resulting from the recall of OMONTYS.

Intellectual Property

We protect our technology through the use of patents, trade secrets and proprietary know-how. WeAs ~~have~~previously ~~more~~announced ~~than~~in 20our ~~issued~~Report ~~U.S.~~on ~~patents~~Form 8-K, ~~including~~filed ~~claims~~April ~~covering~~10, ~~compositions~~2013, ofwe ~~compounds~~entered ~~comprising~~into ~~peptides~~the ofFourth aAmendment ~~broad~~(the ~~genus~~"Amendment") between us and Takeda Pharmaceutical Company Limited amending the Collaboration and License Agreement of ~~ESA~~February ~~peptide~~13, ~~sequences~~2006 and June 27, ~~methods~~2006 ofCollaboration ~~treating~~and ~~EPO~~License ~~disorders~~Agreements ~~using~~to ~~these~~amend ~~compounds~~and restate the ongoing respective roles and ~~methods~~responsibilities ofand ~~synthesizing~~related ~~these~~commitments ~~types~~and offinancial ~~ESA~~terms ~~peptide~~between ~~compounds. Our~~the ~~issued~~parties, ~~U.S.~~including ~~patent(s)~~the ~~covering~~termination ~~OMONTYS~~of the Collaboration and ~~any~~License ~~U.S.~~Agreement ~~patent(s)~~dated ~~that~~as ~~may~~of ~~issue~~February ~~based~~13, on2006, ~~pending~~under ~~patent~~which ~~applications~~Affymax ~~containing~~has ~~claims~~granted ~~covering~~Takeda ~~OMONTYS~~a ~~including~~certain ~~issued~~right ~~claims~~and ~~relating~~license tofor ~~composition~~the development and commercialization in Japan of ~~matter~~OMONTYS, ~~begin~~as ~~expiring~~amended noby ~~earlier~~the ~~than~~First ~~2024. We~~Amendment, ~~own~~dated ~~several~~April ~~pending~~1, ~~U.S.~~2007, ~~patent~~the ~~applications~~Second Amendment, ~~all~~dated ofJanuary ~~which~~1, ~~relate~~2008 toand ~~our~~the ~~core~~Third ~~peptide~~Amendment, ~~technologies~~dated orNovember to7, ~~particular~~2011, ~~peptide~~as ~~compounds. We~~well ~~own~~as ~~foreign~~the ~~equivalent~~related ~~patents~~manufacturing supply, safety, quality and ~~patent~~co-promotion ~~applications~~agreements ~~based~~between onthe ~~our~~parties ~~U.S.~~(collectively, ~~patents~~as ~~and~~amended, ~~patent~~the ~~applications~~"Agreement"). WeThe ~~also~~Amendment ~~retain~~changed ~~technical~~not ~~information~~only ~~related~~the tofinancial ~~manufacture~~terms ~~and~~of ~~analysis~~the relationship but also involved the transfer to Takeda of ~~OMONTYS~~all asthe ~~trade~~intellectual ~~secrets~~property rights, including the control of patent prosecution matters.

WeThroughout ~~own~~the ~~and~~course ~~have~~of ~~rights~~the toyear, ~~several~~Takeda ~~proprietary~~has ~~peptide~~elected ~~screening~~to ~~technologies,~~limit ~~including~~or terminate the ~~patented~~continued ~~technologies~~prosecution of ~~peptide~~the ~~phage~~various ~~display~~U.S. and ~~peptides-on-plasmids~~international patents covering OMONTYS, including those covering most of the European countries. ~~This~~We ~~technology~~have ~~enables~~elected, usas tois ~~identify~~our ~~initial~~right ~~novel~~under ~~peptide~~the ~~sequences~~Agreement, ~~and~~not ~~provides~~to ~~information~~continue ~~that~~prosecution ~~our~~of ~~scientists~~those ~~can~~patents ~~use~~when Takeda has determined to ~~design~~terminate aits ~~variety~~prosecution ofrights ~~peptide~~for ~~compounds~~such patents. Accordingly, we or Takeda will likely not be able to ~~optimize~~maintain ~~bioactivity~~patent ~~and~~protection ~~produce~~for ~~pharmaceutical~~OMONTYS ~~candidate~~in ~~compounds~~any ~~having~~country, ~~desired~~including ~~properties~~the U.S., should the product be reintroduced into the market.

The table below sets forth our ESA-related U.S. patents and their current anticipated expiry and a related description of related foreign patents as provided below:

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ESA-Related U.S. Patents Assigned or Exclusively Licensed

Pat No.	Title	Expiry
5,773,569	Compounds and Peptides that Bind to the Erythropoietin Receptor	6/30/2015
5,830,851	Methods of Administering Peptides that Bind to the Erythropoietin Receptor	11/3/2015
5,986,047	Peptides that Bind to the Erythropoietin Receptor	11/19/2013
6,703,480	Peptide Dimers as Agonists of the Erythropoietin (EPO) Receptor and Associated Methods of Synthesis and Use	11/24/2019
7,084,245	Peptides that Bind to the Erythopoietin Receptor	5/12/2024
7,414,105	Peptides that Bind to the Erythopoietin Receptor	5/12/2024
7,459,522	Peptide Dimers as Agonists of the Erythropoietin (EPO) Receptor and Associated Methods of Synthesis and Use	11/24/2019
7,528,104	Peptides that Bind to the Erythopoietin Receptor	5/12/2024
7,550,433	Erythropoietin Receptor Peptide Formulations and Uses	6/2/2026
7,855,175	Peptides that Bind to the Erythopoietin Receptor	5/12/2024
7,906,485	Erythropoietin Receptor Peptide Formulations and Uses	6/2/2026
7,919,118	Spacer Moiety for Poly(ethylene glycol)-Modified Peptide-Based Compounds	5/12/2024
7,919,461	Erythropoietin Receptor Peptide Formulations and Uses	6/2/2026
8,106,154	Nitrogen-Based Linkers for Attaching Modifying Groups to Polypeptides and Other Molecules	10/5/2029
8,304,391	Peptides that Bind to the Erythropoietin Receptor	5/12/2024
8,324,159	Erythropoietin Receptor Peptide Formulations and Uses	6/26/2026

In addition to the U.S. patents listed above, we own or have exclusive licenses to corresponding foreign patents in various countries outside the U.S.; these foreign counterpart patents are substantially similar to their counterpart U.S. patents. The foreign counterparts to the listed U.S. patents are scheduled to expire in various countries during the period 2015 to 2026.

As a result of uncertainty surrounding OMONTYS and our prospects, we plan to evaluate strategies to decrease our ongoing patent prosecution and maintenance costs, which may result in the abandonment or transfer of any or all of the above patents or applications.

In November 2011, we entered into a settlement and license agreement with Janssen Biotech, Inc. (a subsidiary of Johnson & Johnson) and certain of its affiliated companies under which we obtained a non-exclusive license to the intellectual property in dispute. See Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations elsewhere in this Annual Report on Form 10-K for more information.

Third Party Intellectual Property

~~Numerous~~We ~~U.S.~~may ~~and~~be ~~foreign~~exposed ~~issued~~to, ~~patents~~or ~~and~~threatened ~~pending patent applications~~with, ~~which~~future ~~are~~litigation ~~owned~~ by third parties, ~~exist~~having inpatent ~~the~~or ~~fields~~other inintellectual ~~which~~property werights ~~and~~alleging that our ~~collaborators~~products, ~~are~~product ~~developing~~candidates ~~products~~and/or proprietary technologies infringe their intellectual property rights. ~~Because~~If ~~patent~~one ~~applications~~of ~~can~~these ~~take~~patents ~~many~~was ~~years~~found to ~~issue~~cover our products, ~~there~~product ~~may~~candidates, beproprietary ~~currently~~technologies ~~pending~~or ~~applications~~their uses, ~~unknown~~we toor ~~us,~~our ~~which~~collaborators ~~may~~would ~~later~~be ~~result~~required into ~~issued~~pay ~~patents~~damages ~~that~~and could be restricted from commercializing our products, product candidates or using our proprietary technologies unless we or they obtain a license to the patent. A license may ~~infringe~~not be available to us or our collaborators on acceptable terms, if at all. In addition, during litigation, the patent holder might obtain a preliminary injunction of other equitable right, which could prohibit us from making, using or selling our products, technologies or methods.

WeThere ~~may~~is besubstantial ~~exposed~~amount ~~to,~~of ~~or threatened with, future~~ litigation byinvolving ~~third parties having~~ patent orand other intellectual property rights ~~alleging~~in ~~that~~the ~~our~~biotechnology ~~products, product candidates~~ and~~/or~~ ~~proprietary~~biopharmaceutical ~~technologies~~industries ~~infringe their intellectual property rights~~generally. If ~~one~~a ofthird ~~these~~party ~~patents~~claims ~~was~~that ~~found to cover our products, product candidates, proprietary technologies or their uses,~~ we or our collaborators ~~could~~infringe beits ~~required~~intellectual toproperty ~~pay damages and could be restricted from commercializing our products~~rights, ~~product candidates or using our proprietary technologies unless~~ we ormay ~~they~~face ~~obtain~~ a ~~license~~number toof ~~the~~issues, ~~patent. A~~including ~~license~~but ~~may~~ not belimited ~~available~~ to, uslitigation ~~or our collaborators on acceptable terms~~expenses, ifsubstantial ~~at all. In addition~~damages, ~~during~~attorney ~~litigation~~fees, ~~the patent holder might obtain a preliminary~~ injunction, orroyalty ~~other equitable right~~payments, ~~which~~cross-licensing ~~could~~of ~~prohibit~~our uspatents, ~~from~~redesign ~~making,~~of ~~using~~our products or ~~selling~~processes ~~our~~and ~~products,~~related ~~technologies~~fees orand ~~methods~~costs.

There is a substantial amount of litigation involving patent and other intellectual property rights in the biotechnology and biopharmaceutical industries generally. If a third party claims that we or our collaborators infringe its intellectual property rights, we may face a number of issues, including but not limited to, litigation expenses, substantial damages, attorney fees, injunction, royalty payments, cross-licensing of our patents, redesign of our products or processes and related fees and costs.

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Research and Development Expenses

We have made substantial investments in research and development, or R&D. We have conducted clinical trial activities using both our internal staff and third-party contract clinical trial service providers. ~~Except in connection with the recall~~ However, we ~~plan~~have tosuspended ~~suspend~~ further investment in R&D, including suspending conduct of clinical trials pending consideration of next steps with OMONTYS.

Prior to approval of OMONTYS for commercial sale in March 2012 by the FDA, we had expensed all costs associated with the production of API as R&D expense. R&D expenses were $5111.79 ~~million~~Million, $7651.37 million, and $9376.63 million, for the years ended December 31, ~~2012~~2013, ~~2011,~~2012 and ~~2010~~2011, respectively.

Business Relationships

Our Collaboration with Takeda

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We entered into a collaboration to develop and commercialize OMONTYS with Takeda pursuant to an agreement in February 2006 and an agreement in June 2006. The February 2006 agreement and the June 2006 agreement are collectively referred to herein as the Arrangement. Under the Arrangement, we and Takeda will co-develop and co-commercialize OMONTYS in the U.S., and Takeda received an exclusive license to develop and commercialize OMONTYS outside of the U.S. Takeda has primary responsibility and bears all costs for OMONTYS clinical development in support of regulatory approval for all territories outside the U.S. and is required to pay us a variable royalty based on annual net sales of OMONTYS outside the U.S.

Revenues in 2013, 2012, ~~2011~~ and ~~2010~~2011 were derived almost exclusively from collaboration revenue from Takeda. From our inception through December 31, ~~2012~~2013, we have received an aggregate of $~~534~~537.5 million from Takeda consisting of $122.0 in upfront license fees, $115.3 million in milestone payments and $~~297~~300.2 million related to profit equalization payments for our share of product profit or loss, the reimbursement of development and commercialization expenses and the purchase of API. We are eligible to receive an aggregate of $357.0 million in additional milestone payments from Takeda upon successful achievement of as yet unmet clinical development and regulatory milestones and sales-based milestones under our Arrangement.

In November 2011, we and Takeda entered into a Commercial API Supply Agreement to formalize our respective responsibilities as they relate to the manufacture and supply of OMONTYS. Under the terms of the agreement, we are responsible for the manufacture and supply of all quantities of API to be used in the development and commercialization of OMONTYS worldwide. Takeda is responsible for the fill and finish steps in the manufacture of OMONTYS worldwide.

Finally, in February 2012, we and Takeda entered into a Co-Promotion Agreement to further specify and formalize the terms and conditions relating to our joint U.S. commercialization activities for OMONTYS, including corporate governance structure and division of roles and responsibilities. Under the Co-Promotion Agreement, we deploy the sales and medical affairs field force but share marketing, account management and payor reimbursement related activities with Takeda. We and Takeda split profits or losses 50/50 in the U.S. To implement our profit equalization arrangement, the Co-Promotion Agreement provides further detail relating to the treatment of full-time equivalent, or FTE, expenses used to calculate eligible commercial expenses incurred by us and Takeda. Consistent with the terms of the Arrangement, Takeda retains final decision making authority with respect to terms related to pricing and contracting and responsibility for distribution activities.

In connection with the recall and in consultation with Takeda, ~~as appropriate,~~ we ~~plan~~have toterminated ~~evaluate~~manufacturing ~~the~~activities. Effective ~~near-term~~April ~~activities~~1, ~~our~~ ~~respective~~2013, ~~rights~~we ~~and~~entered ~~obligations~~into ofan ~~the~~amendment ~~parties~~of ~~under~~our ~~the~~collaboration ~~agreements.~~with ~~including~~Takeda ~~the~~pursuant ~~deployment~~to ofwhich ~~resources~~Takeda asassumed ~~part~~full ofresponsibility ~~our~~for ~~efforts~~OMONTYS, toincluding ~~decrease~~responsibility ~~our~~for the ongoing ~~costs~~recall and ~~commitments~~investigation with the FDA, ~~which~~and ~~may~~we ~~negatively~~granted ~~impact~~them ~~our~~an ~~ability~~exclusive license to ~~reintroduce~~ OMONTYS, ifin ~~such~~consideration ~~opportunity~~for ~~arises~~potential royalties and milestones. WeIn ~~are~~addition, ~~particularly~~Takeda ~~dependent~~assumed onfull ~~Takeda's~~responsibility ~~willingness~~for any subsequent decisions as to ~~continue~~whether the ~~collaboration~~product inmay abe ~~modified~~subject ~~form~~to ~~that~~reintroduction ~~reduces~~if ~~our~~Takeda ~~operating~~is ~~expenses~~able to complete the investigation and ~~responsibilities~~address ~~under~~the safety concerns to the ~~collaboration,~~satisfaction ~~and~~of wethe ~~may~~FDA. We ~~also~~provided betransition ~~required~~support to ~~reduce~~Takeda ~~our~~through ~~share~~April of30, ~~OMONTYS~~2013. After ~~profits~~April if30, ~~and~~2013 ~~when~~we ~~the~~have ~~product~~no ~~may~~performance beobligations ~~reintroduced~~under inour ~~the~~agreement ~~future~~with Takeda.

Our License, Manufacturing and Supply Agreement with Nektar

In April 2004, we entered into a License, Manufacturing and Supply Agreement with Nektar under which we obtained from Nektar a worldwide, non-exclusive license, with limited rights to grant sublicenses, under certain intellectual property covering pegylation technology to manufacture, develop and commercialize OMONTYS. The license we obtained consists of a license under intellectual property owned by Nektar and a sublicense under intellectual property owned by Enzon Pharmaceuticals, Inc., or Enzon, licensed to Nektar pursuant to a cross-license agreement between Nektar, Inhale Therapeutic Systems, Inc. and Enzon.

In consideration of the license grant, we agreed to pay royalties on the sales of OMONTYS, which began with the launch of the product in the U.S. in 2012. We also agreed to pay base milestones plus possible additional milestones in connection with our partnering activities relating to OMONTYS, all of which have been paid.

8 Contract Manufacturing Organization (CMO) Settlements

December 31, 2012, we had future purchase commitments amounting to $34.6 million. These future commitments were

comprised of $5.8 million for firm purchase commitments of PEG, and the remaining $28.8 million of manufacturing

obligations relate to API, and were based on firm demand forecasts from Takeda. We paid $1.7 million in payments to our

CMOs in the first quarter of 2013 which reduced the accrual balance to $32.9 million.

We finalized settlement agreements with the CMOs in the second quarter of 2013 and made a total of $11.0 million in

payments resulting in a favorable adjustment to our 2013 operating results of $21.9 million. As of December 31, 2013 we have no remaining future purchase commitments for manufacturing activities.

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with our partnering activities relating to OMONTYS, all of which have been paid. As of December 31, 2012, our remaining milestone obligation is triggered upon acquisition or merger activities.

This agreement expires, on a country by country basis, upon the expiration of our royalty payment obligations. The agreement may be terminated by either party for the other party's material breach provided that such other party has been given a chance to cure such breach, or by Nektar for our challenge of the validity or enforceability of any patents licensed thereunder.

Marketing and Sales

In 2012, we co-commercialized OMONTYS under our Arrangement with Takeda. The commercial launch of the product occurred in April 2012. We established commercial and medical affairs infrastructures in 2012. The functions of our commercial and medical affairs infrastructures included marketing and sales, medical education, coverage and reimbursement and account management. We marketed our product primarily to dialysis organizations. Associated costs are included in selling, general and administrative, or SG&A, costs in our accompanying financial statements. On February 23, 2013, we and Takeda announced a nationwide voluntary recall of OMONTYS and we suspended all the promotional activities and marketing of OMONTYS.

Before the voluntary recall of OMONTYS, Takeda was responsible for account management, pricing and contracting. Specifically, Takeda had sole responsibility for invoicing and collection of receivables with regard to sales of OMONTYS. Takeda sold primarily to pharmaceutical wholesale distributors in the U.S. and Puerto Rico as the principal means of distributing OMONTYS to healthcare providers, which are primarily large dialysis organizations and to a lesser extent medium and small dialysis organizations. Under our Arrangement with Takeda, Takeda also has the rights and responsibility for establishing and modifying terms and conditions with customers with respect to the sale of OMONTYS in the U.S., including pricing discounts available to third-party payors, price adjustments and other allowable discounts and allowances. ~~Both~~In ~~parties~~connection ~~also~~with ~~have~~the ~~shared~~recall ~~responsibilities~~and ~~such~~in asconsultation ~~joint~~with Takeda, we have terminated sales and marketing activities. Effective April 1, ~~business~~2013, ~~analytics~~we entered into an amendment of our collaboration with Takeda pursuant to which Takeda assumed full responsibility for OMONTYS, including responsibility for the ongoing recall and ~~account~~investigation ~~management~~with ~~allocated~~the byFDA, ~~customer~~and ~~segments~~we granted them an exclusive license to OMONTYS in consideration for potential royalties and milestones. In addition, Takeda assumed full responsibility for any subsequent decisions as to whether the product may be subject to reintroduction if Takeda is able to complete the investigation and address the safety concerns to the satisfaction of the FDA. We provided transition support to Takeda through April 30, 2013. After April 30, 2013 we have no performance obligations under our agreement with Takeda.

Before the voluntary recall of OMONTYS, Takeda sold primarily to pharmaceutical wholesale distributors in the U.S. and Puerto Rico as the principal means of distributing OMONTYS to healthcare providers, which are primarily large dialysis organizations and to a lesser extent medium and small dialysis organizations. As all product has been recalled and we are undertaking measures including a significant reduction of force involving the commercial and medical affairs resources and field forces, which may negatively impact our ability to reintroduce OMONTYS even if we are able to successfully identify and address the cause of patients' hypersensitivity in the near term, which is highly uncertain.

Competition

We operate in highly competitive segments of the biotechnology and biopharmaceutical markets. We face competition from many different sources, including commercial pharmaceutical and biotechnology enterprises, academic institutions, government agencies and private and public research institutions. Many of our competitors have significantly greater financial, product development, manufacturing and marketing resources than us. Large pharmaceutical companies have extensive experience in clinical testing and obtaining regulatory approval for drugs. These companies also have significantly greater research capabilities than us. Many universities and private and public research institutes are active in chronic kidney disease research, some in direct competition with us. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies.

If OMONTYS is able to be reintroduced, competing drugs include EPOGEN and potentially Aranesp, which are both marketed by Amgen, Inc., or Amgen. Aranesp, introduced in 2001, has significant market share in the U.S, particularly in the oncology and the non-dialysis markets, although it is approved for treatment in dialysis patients as well. In Europe, Roche has obtained regulatory approval to market, and has launched, a PEGylated ESA called Mircera. Mircera reportedly has greater plasma stability than any of the currently marketed products. PEG is a polymer that increases the time rEPO remains in the circulation and consequently can be dosed less frequently. Mircera has also obtained regulatory approval in the U.S., but as a result of Roche and Amgen's patent infringement litigation, Mircera has been found to infringe several U.S. patents owned by Amgen and has been enjoined from being sold in the U.S. until mid-2014 under the terms of a limited license. If Mircera enters the U.S. market, we believe it will be in direct competition with OMONTYS, if weTakeda ~~are~~is able to reintroduce the product, because of Mircera's ability to be long-acting; therefore, it could potentially limit the market for OMONTYS.

The introduction of biosimilars into the rEPO market in the U.S. will constitute additional competition for OMONTYS if weTakeda ~~are~~is able to reintroduce the product. A biosimilar product is a subsequent version of an existing, branded biologic product. The patent for the existing, branded product must expire in a given market before biosimilars may enter that market. The patents for epoetin alfa, a version of rEPO, expired in 2004 in the E.U., and the remaining patents expired in 2012 through 2015 in the U.S. Several biosimilar versions of rEPO are available for sale in the E.U. and biosimilar versions of rEPO are currently being studied in clinical trials in the U.S. For example, in January 2012, Hospira, Inc. announced the beginning of its Phase 3 clinical program for its biosimilar with results anticipated in 2013, and in October 2012, Sandoz announced the beginning of its Phase 3 clinical program for its biosimilar with results anticipated in 2014. Upon entry into the U.S. market, biosimilars will compete with OMONTYS, when and if Takeda reintroduces the product, and will drive down its price and sales volume, which would adversely affect our revenues.

9OMONTYS may also face competition from potential new anemia therapies if and when Takeda reintroduces OMONTYS. There are several product candidates in various stages of active development for anemia indications by potential competitors that may promote the production of naturally-occurring EPO in patients, and some of these product candidates may

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~~compete~~enter the market as early as 2015. If these product candidates enter the market they may be in direct competition with OMONTYS, ~~when~~if and ifwhen weit ~~reintroduce~~is ~~the~~reintroduced. In ~~product~~addition, ~~and~~certain ~~will~~companies ~~drive~~are ~~down~~developing ~~its~~potential ~~price~~new therapies for renal-related diseases that could reduce ESA utilization and ~~sales~~thus ~~volume,~~limit ~~which~~the ~~would~~market ~~adversely~~for ~~affect~~OMONTYS ~~our~~if ~~revenues~~and when it is reintroduced.

WeIf ~~may~~and ~~also~~when ~~face~~Takeda ~~competition~~is ~~from~~able ~~potential~~to ~~new anemia therapies if and when we~~ reintroduce OMONTYS~~. There~~, ~~are~~which ~~several~~is ~~product~~highly ~~candidates~~uncertain, init ~~various~~will ~~stages~~be ofeven ~~active~~more ~~development~~challenging ~~for~~to ~~anemia~~compete ~~indications by potential competitors that may promote the production of naturally-occurring EPO~~ in ~~patients,~~view ~~and some~~ of ~~these product candidates may enter~~ the ~~market~~recall asand ~~early~~related assafety ~~2015. If~~concerns ~~these~~particularly ~~product~~due ~~candidates~~to ~~enter~~ the ~~market~~long-term ~~they~~experience ~~may be in direct competition~~ with ~~OMONTYS~~currently ifmarketed ~~and~~products ~~when it is reintroduced. In addition, certain companies are developing potential new therapies for renal-related diseases that could reduce ESA utilization~~ and ~~thus~~negative ~~limit~~perceptions ~~the~~of ~~market for~~ OMONTYS' ~~if and when it is reintroduced~~safety.

If and when we are able to reintroduce OMONTYS, which is highly uncertain, it will be even more challenging for us to compete in view of the recall and related safety concerns particularly due to the long-term experience with currently marketed products and negative perceptions of OMONTYS' safety. These factors present further challenges to compete and enter into long-term supply agreements with the major operators of dialysis clinics in the U.S. In particular, we may not be able to reach a long-term agreement with either of the largest operators of dialysis clinics in the U.S., DaVita Inc., or DaVita, and Fresenius, because both entered into a long-term supply agreement with Amgen that began in January 2012. In July 2012, Fresenius entered into a short-term supply agreement with Takeda Pharmaceuticals America, Inc., or TPA. In February 2013, Fresenius communicated that it decided to pause further expansion of its OMONTYS pilot program.

Even if we are able to successfully address safety issues for OMONTYS with the FDA, we believe it may be more challenging to continue with or expand upon the short-term supply agreement with Fresenius in the near term. In any event, Amgen's long-term supply agreements with DaVita and Fresenius and the potential introduction of Mircera and biosimilars may limit the market opportunity for OMONTYS and adversely impact our ability to generate product sales should we reintroduce the product.

Government Regulation and Product Approvals

FDA and EMA

OMONTYS is subject to regulation by various authorities in the U.S., the E.U. and other countries, including the FDA in the U.S. and the European Medicines Agency, or EMA, in the E.U. In the U.S., pharmaceutical products are subject to extensive regulation by the FDA. The Federal Food, Drug, and Cosmetic Act and other federal and state statutes and regulations, govern, among other things, the research, development, testing, manufacture, storage, recordkeeping, approval, labeling, promotion and marketing, distribution, post-approval monitoring and reporting, sampling, and import and export of pharmaceutical products. The FDA has very broad enforcement authority and failure to abide by applicable regulatory requirements can result in administrative or judicial sanctions being imposed on us, including warning letters, refusals of government contracts, clinical holds, civil penalties, injunctions, restitution, disgorgement of profits, recall or seizure of products, total or partial suspension of production or distribution, withdrawal of approval, refusal to approve pending applications, and criminal prosecution.

Product development and approval within these regulatory frameworks takes a number of years, and involves the expenditure of substantial resources. Regulatory approval is required in all major markets in which products will be tested in development. At a minimum, such approval requires evaluation of data relating to quality, safety and efficacy of a product for its proposed use. The specific types of data required and the regulations relating to these data differ depending on the territory, the drug involved, the proposed indication and the stage of development.

In the U.S., specific pre-clinical data, chemical data and a proposed clinical study protocol must be submitted to the FDA as part of an Investigational New Drug application, or IND, which, unless the FDA objects, will become effective 30 days following receipt by the FDA. Phase 1 trials may commence only after the IND application becomes effective. Prior regulatory approval for human healthy volunteer studies is also required in member states of the E.U. Currently, in each member state of the E.U., following successful completion of Phase 1 trials, data are submitted in summarized format to the applicable regulatory authority in the member state in respect of applications for the conduct of later Phase 2 trials. In the U.S., following successful completion of Phase 1 trials, further submissions to regulatory authorities are necessary in relation to Phase 2 and 3 trials to update the existing IND. Authorities may require additional data before allowing the trials to commence and could demand discontinuation of studies at any time if there are significant safety concerns. In addition to regulatory review, a clinical trial involving human subjects has to be approved by an independent body. The exact composition and responsibilities of this body differ from country to country.

Information generated in the clinical trial process is susceptible to varying interpretations that could delay, limit, or prevent regulatory approval at any stage of the approval process. Failure to demonstrate adequately the quality, safety and efficacy of a therapeutic drug under development would delay or prevent regulatory approval of the product and even if clinical trials were successfully completed, there could be no assurance that applications for required authorizations to manufacture or market potential products would be submitted, or that any such application would be reviewed and approved by appropriate regulatory authorities in a timely manner, if at all. In order to gain marketing approval, a dossier must be submitted to the relevant authority for review, which is known in the U.S. as an NDA, and in the E.U. as a Marketing Authorization Application, or MAA. In February 2012, Takeda submitted a MAA that was accepted by the EMA. However, in light of the recent OMONTYS recall for safety concerns, in 2013 the MAA submission was withdrawn.

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trials were successfully completed, there could be no assurance that applications for required authorizations to manufacture or market potential products would be submitted, or that any such application would be reviewed and approved by appropriate regulatory authorities in a timely manner, if at all. In order to gain marketing approval, a dossier must be submitted to the relevant authority for review, which is known in the U.S. as a NDA, and in the E.U. as a Marketing Authorization Application, or MAA. In February 2012, Takeda submitted a MAA that was accepted by the EMA. However, in light of the recent OMONTYS recall for safety concerns, there can be no assurance that this application will be approved by the EMA.

U.S. Approval Process

OMONTYS is regulated by the FDA as a drug. In the U.S., no manufacturer may market a new drug until it has submitted a NDA to the FDA, and the FDA has approved it. The steps required before the FDA may approve a NDA generally include:


•	preclinical laboratory tests and animal tests conducted in compliance with FDA's good laboratory practice requirements;


•	development, manufacture and testing of API and dosage forms suitable for human use in compliance with current good manufacturing practices, or GMP;

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•	the submission to the FDA of an IND for human clinical testing, which must become effective before human clinical trials may begin;


•	adequate and well-controlled human clinical trials to establish the safety and efficacy of the product for its specific intended use(s);


•	the submission to the FDA of a NDA; and


•	FDA review and approval of the NDA.

FDA approval of the NDA is required before marketing of the product may begin in the U.S.

E.U. Approval Process

In the E.U., there is, for many products, a choice of two different authorization routes: centralized and decentralized. Under the centralized route, one marketing authorization is granted for the entire E.U., while under the decentralized route a series of national marketing authorizations are granted. In the centralized system, applications are reviewed by members of the Committee for Medicinal Products for Human Use, on behalf of the EMA. The EMA will, based upon the review of the Committee for Medicinal Products for Human Use, provide an opinion to the European Commission on the safety, quality and efficacy of the product. The decision to grant or refuse an authorization is made by the European Commission. In circumstances where use of the centralized route is not mandatory, we can choose to use the decentralized route, in which case the application will be reviewed by each member state's regulatory agency. If the regulatory agency grants the authorization, other member states' regulatory authorities are asked to "mutually recognize" the authorization granted by the first member state's regulatory agency. Approval can take several months to several years or be denied. The approval process can be affected by a number of factors. Additional studies or clinical trials may be requested during the review and may delay marketing approval and involve unbudgeted costs. Regulatory authorities may conduct inspections of relevant facilities and review manufacturing procedures, operating systems and personnel qualifications. In addition to obtaining approval for each product, in many cases each drug manufacturing facility must be approved. Further, inspections may occur over the life of the product. An inspection of the clinical investigation sites by a competent authority may be required as part of the regulatory approval procedure. As a condition of marketing approval, the regulatory agency may require post-marketing surveillance to monitor adverse effects, or other additional studies as deemed appropriate. After approval for the initial indication, further clinical trials are usually necessary to gain approval for additional indications. The terms of any approval, including labeling content, may be more restrictive than expected and could affect product marketability. In February 2012, Takeda submitted a MAA that was accepted by the EMA under the centralized authorization route. ~~Approval~~However, byin ~~the~~light ~~FDA~~of ~~does not ensure approval by~~ the ~~EMA and the~~ recent OMONTYS recall for safety concerns, ~~makes approval by~~ the ~~EMA~~MAA ~~more~~submission ~~challenging~~was ~~in the near term~~withdrawn.

Federal and State Healthcare Laws

Pharmaceutical companies are subject to various federal and state healthcare laws. These healthcare laws include: federal "sunshine laws" that require transparency regarding financial arrangements with healthcare providers; the federal Anti-Kickback Law that prohibits, among other things, persons from knowingly and willfully soliciting, receiving, offering or paying remuneration in exchange for referral of an individual for, or the purchase, order or recommendation of, any good or service for which payment may be made under federal healthcare programs such as Medicare and Medicaid; federal false claims laws which prohibit, among other things, individuals or entities from knowingly presenting false claims for payment from Medicare, Medicaid or other third-party payors; and state law equivalents of each of these federal laws. Because of the far-reaching nature of these laws, there can be no assurance that we will be able to strictly comply with these laws.

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Coverage and Reimbursement

The Centers for Medicare and Medicaid Services, or CMS, the government agency that manages Medicare and is responsible for coverage of OMONTYS for Medicare beneficiaries, has significantly restricted coverage of ESAs in response to the FDA's boxed warning, ESA class labeling changes, and public health advisories. As the costs of the Medicare program continue to grow, CMS may also be compelled to make difficult decisions regarding the trade-offs of certain public health expenditures over others.

Further, prior to January 1, 2011, CMS reimbursed healthcare providers for use of ESAs at average selling price plus 6%. However, under the 2008 Medicare Legislation a new bundled payment system commenced in January 2011 for facilities that furnish renal dialysis services to Medicare beneficiaries with end-stage renal disease. Under the new bundled payment system, providers are reimbursed a fixed amount per patient, including for ESAs such as OMONTYS. In January 2013, Congress enacted legislation to reduce the overall bundled payment to dialysis providers beginning in January 2014. This new capitated reimbursement payment methodology has created incentives for significantly lower utilization or dosing of ESAs, including OMONTYS, and has reduced the commercial potential for the product.

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Finally, as a result of CMS coverage and reimbursement changes, third-party payors are increasingly attempting to contain health care costs by limiting both coverage and the level of reimbursement of new drugs. Third-party payors have begun to follow CMS' restrictive reimbursement policies, which has further decreased the market for ESAs. As a result, significant uncertainty exists as to whether and how much third-party payors will reimburse patients for their use of ESAs, which in turn will put pressure on the pricing and utilization of the product. When and if we reintroduce OMONTYS, and coverage and reimbursement are available, which is uncertain, we expect to experience pricing pressures in connection with the sale of OMONTYS due to the trend toward managed health care and the adoption of government coverage and reimbursement policies.

Employees

As of December 31, ~~2012~~2013, we had ~~304~~4 employees~~. We had 71 employees engaged in research and development~~, ~~and~~all ~~the remainder~~ of ~~our~~whom ~~employees~~ were engaged in ~~other SG~~G&A functions ~~or medical affairs~~. We ~~have undertaken measures to reduce our workforce by approximately 230 employees and anticipate that further reductions may be in order as we endeavor to conserve our cash resources.~~

Available Information

We file electronically with the U.S. Securities and Exchange Commission our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities and Exchange Act of 1934. We make available on our website at www.affymax.com, free of charge, copies of these reports as soon as reasonably practicable after we electronically file such material with, or furnish it to, the Securities and Exchange Commission. Further, copies of these reports are located at the Securities and Exchange Commission's Public Reference Room at 100 F Street, NE, Washington, D.C. 20549. Information on the operation of the Public Reference Room can be obtained by calling the Securities and Exchange Commission at 1-800-SEC-0330. The Securities and Exchange Commission maintains a website that contains reports, proxy and information statements, and other information regarding our filings, at www.sec.gov. The information contained in, or that can be accessed through, our website is not part of, and is not incorporated into, this Annual Report on Form 10-K.

Item 1A. Risk Factors

Our business faces significant risks, some of which are set forth below to enable readers to assess, and be appropriately apprised of, many of the risks and uncertainties applicable to the forward-looking statements made in this Annual Report on Form 10-K. You should carefully consider these risk factors as each of these risks could adversely affect our business, operating results and financial condition. If any of the events or circumstances described in the following risks actually occurs, our business may suffer, the trading price of our common stock could decline and our financial condition or results of operations could be harmed. Given these risks and uncertainties, you are cautioned not to place undue reliance on forward-looking statements. In assessing these risks, you should also refer to the other information contained in this Annual Report on Form 10-K, including our financial statements and related notes. The risks and uncertainties described below are not the only ones we face. Additional risks and uncertainties not presently known to us, or that we currently believe to be immaterial, may also adversely affect our business.

Risks Related to Our Business

In February 2013, we recalled OMONTYS nationwide due to safety concerns and OMONTYS may not be reintroduced to the market unless Takeda is able to identify and successfully address the causes of the safety concerns with the FDA. OMONTYS was our only product and the recall has severely harmed our business. We face significant challenges to our business and we have ceased most company operations and may not be able to continue our business as a result of the recall.

In February 2013, we announced the voluntary nationwide recall of OMONTYS from the market resulting from serious allergic reactions reported in patients receiving the product, including anaphylaxis related to deaths occurring after first administration of OMONTYS. While Takeda continues to investigate these cases and the nature and causes of the safety concerns, if Takeda is unable to rapidly identify and rectify the causes, the product could be permanently withdrawn from the market. The recall has severely harmed our business and financial condition and prospects as a going concern and we have ceased most company operations and may not be able to continue our business.

In order to address the safety concerns resulting in the recall of OMONTYS, Takeda would have to complete its ongoing thorough investigation, identify the causes of the serious allergic reactions and provide a suitable plan to the FDA for approval. To date, no causes have been identified and we are unable to predict when, or if, this process may be completed or the associated costs. Further, in an effort to continue our operations in the near term with our limited resources, we have substantially reduced our operating costs, including a reduction in force of nearly all of our employees and cessation of most

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operating functions. The Brenner Group, Inc., a restructuring firm, has been retained to oversee and implement the ongoing operations.

There can be no assurance that our business can continue or OMONTYS can be shown to be sufficiently safe to meet the requirements of the FDA for reintroduction by Takeda. Moreover, even if OMONTYS could be reintroduced, the commercial prospects for the product may be permanently diminished, coverage and reimbursement may not be available, and the product may no longer be commercially viable.

We have incurred significant operating losses since inception and anticipate that we will incur continued losses for the foreseeable future without revenues from OMONTYS, which was our only product. We have undertaken a restructuring and have limited resources with which to continue basic company operations until the future of OMONTYS (if any) is determined. If the Takeda led investigation takes an extended period, or results in OMONTYS not being reintroduced commercially to the market, we may need to cease operations.

We have experienced significant operating losses since our inception in 2001. At December 31, 2013, we had an accumulated deficit of $558.1 million. Due to the recall of OMONTYS, the subsequent restructuring and the uncertainty of when or if we may receive any potential royalties or milestones based on any revenues from the product under our amended collaboration with Takeda, we have limited resources with which to continue our operations and we have substantial ongoing obligations. In particular, we expect to continue to spend significant amounts in defense of our existing and potential future litigation.

As a result of the recall and the subsequent restructuring, we believe that we have enough cash to fund our resources through the third quarter of 2014. Even with our restructuring efforts, including the termination of substantially our entire workforce, there is no assurance that our reduced resources will be sufficient to meet our existing obligations and conduct ongoing operations. If Takeda is not able to reintroduce OMONTYS or we are not able to obtain additional funding, our cash resources will rapidly be depleted and we may need to cease operations.

To date, our sources of cash have been limited primarily to the proceeds from the sale of our securities to private and public investors and payments by Takeda under our collaboration agreements. Further challenges or delays related to Takeda's potential reintroduction of OMONTYS or our restructuring efforts could require us to raise additional funds to continue our operations. We cannot be certain that additional funding will be available on acceptable terms, or at all. To the extent that we raise additional funds by issuing equity securities, if available, our stockholders may experience significant dilution.

If Takeda is unable to identify the causes of the OMONTYS safety concerns and commercialize OMONTYS successfully, or we are unable to negotiate and satisfy our obligations, or raise additional funds when required or on acceptable terms, we may have to:


•	discontinue operations;


•	abandon or relinquish some or all of our existing rights to OMONTYS milestones, royalties or other existing rights; or


•	pursue alternatives such as a sale of the Company or its assets, a corporate merger, wind-down of operations or even bankruptcy proceedings.

Our ability to obtain potential royalties or milestones from Takeda under our amended collaboration and our ability to continue as a going concern depend directly on Takeda's ability to successfully reintroduce and commercialize OMONTYS, which is highly uncertain and challenging. OMONTYS will require significant marketing efforts and substantial investment before it can provide any meaningful revenue, if ever. Even if the underlying causes of the safety concerns can be identified, which is uncertain, the timelines associated with the investigation and the feasibility and costs associated with implementing solutions to address the safety concerns to the satisfaction of the FDA are highly uncertain.

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~~Risks~~We ~~Related~~may be unable to ~~Our~~continue ~~Business~~our operations or meet our ongoing obligations as a result of the loss of services of substantially all of our personnel as part of our restructuring.

We ~~have~~As ~~recently~~of ~~recalled~~June ~~OMONTYS~~30, ~~nationwide~~2013 ~~due~~we todramatically ~~safety~~reduced ~~concerns~~our workforce and ~~OMONTYS~~engaged ~~may~~an ~~not~~experienced berestructuring ~~reintroduced~~firm, toThe ~~the~~Brenner ~~market~~Group, ~~unless~~Inc. With weour ~~are~~engagement ~~able~~of toThe ~~rapidly~~Brenner ~~identify~~Group, ~~and~~Inc., ~~successfully~~we ~~address~~terminated the ~~causes~~employment of ~~the~~our ~~safety~~former ~~concerns~~executive ~~with~~officers, ~~the~~including ~~FDA. OMONTYS is~~ our ~~only~~Chief ~~product~~Executive Officer and ~~the~~Chief ~~recall~~Financial ~~has severely harmed our business~~Officer. WeAs ~~face~~a ~~significant~~result ~~challenges~~of tothe ~~our~~loss ~~business. We~~of ~~may~~services ~~have~~of tosubstantially ~~abandon~~all orof ~~relinquish~~our ~~some~~personnel, orincluding all of our ~~product~~executive ~~rights. Accordingly~~officers, we may ~~not~~ be ~~able~~unable to continue ~~the~~our ~~business~~operations and ~~operations~~meet ofour ~~the~~ongoing ~~company~~obligations aseven awith ~~result~~our engagement of ~~these~~the ~~safety~~restructuring ~~concerns~~firm.

WeOur ~~recently~~independent ~~announced~~registered ~~the~~public ~~voluntary~~accounting ~~nationwide~~firm ~~recall~~has ofindicated ~~OMONTYS~~that ~~from~~our ~~the~~financial ~~market~~condition ~~resulting~~raises ~~from~~substantial ~~serious~~doubt ~~allergic~~as ~~reactions reported in patients receiving OMONTYS, including anaphylaxis related~~ to ~~deaths~~our ~~occurring~~ability ~~after first administration of OMONTYS. While we continue~~ to investigate these cases and the nature and causes of the safety concerns, if we are unable to rapidly identify and rectify the causes, the product could be permanently withdrawn from the market and we may be unable to continue as a going concern. ~~The~~ ~~recall has severely harmed our business and financial condition and prospects as a going concern and we may not be able to continue the business and operations of the company.~~

InOur ~~order~~independent toregistered ~~address~~public ~~the~~accounting ~~safety~~firm ~~concerns~~has ~~resulting~~included in their audit opinion on our financial statements for the ~~recall~~year ofended ~~OMONTYS~~December 31, we2013, ~~would~~a ~~have~~statement with respect to ~~complete~~substantial doubt as to our ~~ongoing~~ability ~~thorough~~to ~~investigation,~~continue ~~identify~~as ~~the~~a ~~causes~~going ofconcern. ~~the~~Our ~~serious~~financial ~~allergic~~statements ~~reactions~~have ~~and~~been ~~provide~~prepared aassuming ~~suitable~~we ~~plan~~will continue to ~~the~~operate ~~FDA~~as ~~for~~a ~~approval. We~~going ~~are~~concern, ~~unable~~which tocontemplates ~~predict~~the ifrealization orof ~~when~~assets ~~this~~and ~~process~~the ~~may~~satisfaction beof ~~completed~~liabilities orin the ~~associated~~normal ~~costs,~~course ~~but~~of business. If we ~~expect~~became ~~that~~unable ~~that~~to ~~investigation~~continue ~~may~~as bea ~~lengthy~~going ~~and~~concern, ~~are~~we ~~uncertain~~may ashave to ~~whether~~liquidate our ~~available~~assets ~~limited~~and ~~resources,~~the ~~particularly~~values inwe ~~light~~receive offor our ~~recent~~assets ~~reductions~~ in ~~our~~liquidation ~~workforce,~~or ~~which~~dissolution ~~may~~could ~~not~~be ~~allow~~significantly uslower tothan ~~complete~~ the ~~process~~values reflected in aour ~~timely~~financial ~~manner~~statements. ~~Further,~~The inreaction anof ~~effort~~investors to ~~continue~~the ~~our~~inclusion ~~operations~~of ina ~~the~~going ~~near~~concern ~~term~~statement ~~with~~in ~~our~~the ~~limited~~report ~~resources,~~of weour ~~will~~independent ~~need~~registered topublic ~~continue~~accounting tofirm, ~~substantially~~our ~~reduce~~lack ~~our~~of ~~operating~~cash ~~costs~~resources, ~~including~~and ~~further~~our ~~reductions~~potential ininability ~~force~~to ofcontinue ~~critical~~as ~~personnel~~a ~~and~~going ~~functions,~~concern ~~even~~may ~~those~~materially ~~directly~~adversely ~~related~~affect toour ~~the~~share ~~conduct~~price ~~of the investigation~~ and ~~support~~our ofability ~~our~~to ~~New~~raise ~~Drug~~new ~~Application~~capital or ~~NDA~~continue ~~for~~our ~~OMONTYS~~operations.

~~There~~If ~~can~~we befail noto ~~assurance~~maintain ~~that~~ our ~~business~~collaboration ~~can~~with ~~continue~~Takeda oras ~~OMONTYS~~recently ~~can~~amended, besuch ~~shown~~termination towould behave ~~sufficiently~~a ~~safe~~further tomaterial ~~meet~~adverse ~~the~~effect ~~requirements~~on ofour ~~the~~business ~~FDA~~and ~~for reintroduction~~operations. ~~Moreover,~~Our ~~even~~business ifhas ~~OMONTYS~~already ~~could~~been beseverely ~~reintroduced,~~harmed by the ~~commercial~~recall ~~prospects~~of ~~for~~OMONTYS, ~~this~~and ~~product~~any ~~may~~termination beof ~~permanently~~the ~~diminished,~~collaboration ~~coverage~~agreement ~~and~~would ~~reimbursement~~substantially ~~may~~reduce ~~not~~our beability ~~available~~to meet our obligations, and may increase the ~~product~~likelihood ~~may~~of nohaving ~~longer~~to becease ~~commercially~~our ~~viable~~operations, even with the ongoing restructuring efforts.

We The ~~have~~maintenance ~~incurred~~of ~~significant~~our ~~operating~~collaboration ~~losses~~with ~~since~~Takeda ~~inception~~for ~~and~~OMONTYS ~~anticipate~~is ~~that~~an weessential ~~will~~part ~~incur~~of ~~continued~~our ~~losses~~business. Completion ~~for~~of the ~~foreseeable~~OMONTYS ~~future~~recall, ~~without~~investigation ~~revenues~~and ~~from OMONTYS~~reintroduction, for which ~~was~~Takeda assumes full responsibility, is critical to our ~~only~~ability ~~product. We~~to ~~have~~achieve ~~undertaken~~any afurther ~~reorganization~~cash flows through potential royalties or milestones. ~~and~~Takeda ifhas wefull ~~are~~decision-making ~~unable~~authority as to ~~substantially~~whether ~~further~~OMONTYS ~~reduce~~may ~~our~~be ~~expenses,~~reintroduced weif ~~may~~Takeda ~~need~~completes the investigation and addresses the safety concerns to ~~cease~~the ~~operations.~~satisfaction of the FDA.

WeMoreover, ~~have~~Takeda ~~experienced~~has ~~significant~~the ~~operating~~right ~~losses~~to ~~since~~terminate our ~~inception~~collaboration upon an uncured material breach by us or even in ~~2001. At~~the ~~December 31~~absence of a material breach with three months notice prior to reintroduction of OMONTYS, ~~2012~~which termination would have a further material adverse effect on OMONTYS and our business and operations, as we ~~had~~would anbe ~~accumulated~~highly ~~deficit~~unlikely ofto ~~$543.7~~be ~~million. Due~~able to assume the ~~recent~~regulatory ~~recall~~responsibilities required to maintain the NDA. In the past, events such as the suspension of the OMONTYS ~~and~~oncology program, the ~~uncertainty~~impact of ~~when~~the orPhase 3 ifresults weon ~~may~~the ~~receive~~renal ~~any~~program ~~revenues~~particularly ~~from~~on ~~OMONTYS~~the non-dialysis indication, weand ~~anticipate~~the decreased market opportunity for ESAs increase the possibility that weTakeda ~~will~~may ~~incur~~elect ~~substantial~~to ~~losses~~terminate inthe ~~future~~collaboration ~~periods. In~~or ~~particular,~~limit wethe ~~expect~~resources Takeda is willing to ~~continue~~commit to ~~spend~~OMONTYS. The ~~substantial~~safety ~~amounts~~concerns inwith ~~order~~OMONTYS combined with the recent U.S. recall may negatively impact the EMA decision if the MAA is resubmitted and Takeda's view of the collaboration and its overall commitment to: OMONTYS, including in the U.S., our major market opportunity.

•We ~~investigate~~are ~~the~~currently ~~causes~~subject ofto ~~reported~~securities ~~patients'~~class ~~hypersensitivity~~action ~~reactions~~litigation and derivative litigation as well as product liability litigation and we may be subject to ~~OMONTYS;~~similar or other litigation in the future.

•We ifand wecertain of our former officers are ~~able~~defendants toin ~~identify~~a ~~and~~lawsuit ~~address~~filed in the ~~safety~~United ~~concerns~~States ~~with~~District ~~OMONTYS~~Court for the Northern District of California, ~~meet~~brought on behalf of stockholders of the ~~requirements~~Company that alleges violations of the ~~FDA~~Securities Exchange Act of 1934 in anconnection ~~effort~~with toallegedly ~~reintroduce~~false and ~~commercialize~~misleading statements made by the defendants regarding OMONTYS; and our business practices, financial projections and other disclosures between August 8, 2012 and February 22, 2013, or the Class Period. The plaintiffs seek to represent a class comprised of purchasers of our common stock during the Class Period and seek damages, costs and expenses and such other relief as determined by the Court.

•In ~~support~~addition, in March 2013 and ~~maintain~~August 2013, a total of three derivative lawsuits were filed purportedly on behalf of the Company in California Superior Court for the County of Santa Clara naming certain of our ~~organizations~~officers and ~~infrastructure~~directors toas ~~manage~~defendants. The ~~and~~lawsuits ~~comply~~allege ~~with~~that certain of our ~~ongoing~~current ~~regulatory~~and former officers and ~~legal~~directors ~~obligations~~breached astheir ~~well~~fiduciary asduties related to ~~support~~the ~~our~~clinical ~~existing~~trials for OMONTYS and ~~potential~~for ~~future~~representations ~~litigation;~~regarding our business health, which was tied to the success of OMONTYS. The lawsuits also assert claims for unjust enrichment and corporate waste. We believe we are entitled to coverage

• maintain or manage our ongoing contractual commitments to third parties including to OMONTYS contract manufacturing organizations, or CMOs to reduce our obligations pending the outcome of the investigation.

As a result of the recall and the suspension of all marketing activities, there is significant uncertainty as to whether we will have sufficient cash, cash equivalents, and investments to fund our operations for at least the next 12 months. Even with the recent reorganization, further reductions in our workforce and cash outflows, there is no assurance that we will be able to reduce our operating expenses enough to meet our existing obligations and conduct ongoing operations. If we are not able to reintroduce the product or obtain additional funding in the near future, our cash resources will rapidly be depleted and we will be required to significantly reduce or suspend operations, which would likely have a material adverse effect on our business, stock price and our relationships with third parties with whom we have business relationships. Further, we may be in breach under our loan and security agreement, or the Loan Agreement, with Oxford Finance LLC and Silicon Valley Bank, or, collectively, the Lenders as the voluntary recall may be considered a material adverse event under the Loan Agreement. Under the Loan Agreement, the Lenders have various rights, including the right to not extend further credit of the remaining $20.0

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~~million~~ under ~~the~~our ~~Loan~~relevant ~~Agreement,~~insurance ~~require immediate repayment of the outstanding principal plus accrued and unpaid interest~~policies, asubject ~~final payment fee and prepayment fee of approximately $2.2 million as of February 28, 2013 and other remedies available under the terms of the Loan Agreement. In order~~ to ~~maintain our efforts to identify and address the safety concerns with OMONTYS, we are undertaking~~ a ~~significant restructuring of the business and operations of the company~~retention, but wecoverage ~~plan~~could tobe ~~continue~~denied toor ~~make~~prove ~~efforts~~ to ~~substantially~~be ~~reduce~~insufficient. In ~~our operating costs~~addition, ~~which~~it ~~will~~is ~~likely~~possible ~~include~~total ~~further~~liability ~~reductions~~could inexceed ~~force as we endeavor to conserve~~ our ~~cash~~insurance ~~resources~~limits.

ToOn ~~date~~or about February 13, ~~our~~2014, ~~sources~~a ofcomplaint ~~cash~~was ~~have~~filed ~~been~~by ~~limited~~an ~~primarily~~individual toplaintiff in the ~~proceeds~~Fourth ~~from~~Judicial District Court (Ouachita Parish) of the ~~sale~~State of ~~our~~Louisiana, ~~securities~~naming toas ~~private~~defendants ~~and~~the ~~public~~Company, ~~investors~~Takeda ~~and~~Pharmaceuticals ~~payments~~America, byInc., Takeda ~~under~~Pharmaceuticals ~~our~~U.S.A., ~~collaboration~~Inc., ~~agreements~~Takeda Development Center Americas, Inc. ~~Further~~, ~~challenges~~Takeda orPharmaceuticals ~~delays~~International, toInc., ~~potential~~Takeda ~~reintroduction~~Pharmaceutical ofCompany ~~OMONTYS~~Limited, ~~could~~Fresenius ~~require~~Medical usCare toMonroe, ~~raise~~LLC, ~~additional~~and ~~funds~~Fresenius Medical Care Holdings, Inc., and indicating an intention to ~~continue~~add ~~our~~two ~~operations~~physicians as defendants. The Weplaintiff ~~cannot~~seeks beto ~~certain~~hold ~~that~~the ~~additional~~defendants ~~funding~~liable ~~will~~in beconnection ~~available~~with the death of her husband on ~~acceptable~~February ~~terms~~15, or2013. The atcomplaint ~~all. To~~alleges that the ~~extent~~Company ~~that~~and wecertain ~~raise~~other ~~additional~~defendants ~~funds~~are byliable ~~issuing~~under ~~equity~~the ~~securities,~~Louisiana ifProducts ~~available~~Liability Act, ~~our~~La.R.S. ~~stockholders~~9:2800.51, ~~may~~et ~~experience~~seq., ~~significant~~other ~~dilution. Our~~Louisiana ~~current~~statutes, ~~debt~~and ~~financing~~otherwise ~~involves~~in ~~security~~connection ~~interests~~with ontheir ~~our~~alleged ~~assets~~acts and ~~restrictive~~omissions ~~covenants,~~with ~~such~~respect asto ~~limitations~~OMONTYS. The onplaintiff ~~our~~seeks ~~ability~~various tocategories ~~incur~~or ~~additional~~types ~~indebtedness~~of damages, ~~limitations~~including, onwithout ~~our~~limitation, ~~ability~~damages tofor ~~acquire~~her and her late husband’s alleged losses and injuries, punitive or ~~license~~exemplary ~~intellectual~~damages, ~~property~~the ~~rights~~price of OMONTYS and ~~other~~reasonable ~~operating~~expenses ~~restrictions~~occasioned by the sale of that ~~could~~drug, ~~adversely~~and ~~impact~~other ~~our~~relief ~~ability~~as set forth in the complaint. We are continuing to ~~conduct~~review the complaint with our ~~business~~partner, Takeda and there can be no assurances that additional products liability complaints will not be brought.

If we are unable to identify quickly the causes of the OMONTYS safety concerns or raise additional funds when required or on acceptable terms, we may have to:

• abandon the investigation, NDA, and any potential to reintroduce OMONTYS ;

• significantly delay, scale back, or discontinue operations;

• abandon or relinquish some or all of our existing rights to OMONTYS;

• eliminate or defer manufacturing efforts that may negatively impact OMONTYS; or

• pursue alternatives such as a sale of the company or its assets, a corporate merger, restructuring, winddown of operations or even bankruptcy proceedings.

Our ability to generate product sales and continue as a going concern depends heavily on our ability to successfully reintroduce and commercialize OMONTYS, which is highly uncertain and challenging. OMONTYS will require significant marketing efforts and substantial investment before it can provide us with any meaningful revenue, if ever. We expect to incur substantial expenses associated with the recall and the ongoing investigation. Even if the underlying causes of the safety concerns can be identified, which is uncertain, the timelines associated with the investigation and the feasibility and costs associated with implementing solutions to address the safety concerns to the satisfaction of the FDA are highly uncertain. Our recent reorganization and future reductions in force of critical personnel and functions may substantially impair the investigation and our ability to maintain our operations and support the NDA. Accordingly, we may never be able to reintroduce OMONTYS or generate significant revenues and, even if OMONTYS is reintroduced so as to generate product sales, we may never achieve or sustain profitability.

Our independent registered public accounting firm has indicated that our financial condition raises substantial doubt as to our ability to continue as a going concern.

Our independent registered public accounting firm has included in their audit opinion on our financial statements for the year ended December 31, 2012, a statement with respect to substantial doubt as to our ability to continue as a going concern. Our financial statements have been prepared assuming we will continue to operate as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. If we became unable to continue as a going concern, we may have to liquidate our assets and the values we receive for our assets in liquidation or dissolution could be significantly lower than the values reflected in our financial statements. The reaction of investors to the inclusion of a going concern statement in the report of our independent registered public accounting firm, our lack of cash resources, and our potential inability to continue as a going concern may materially adversely affect our share price and our ability to raise new capital or continue our operations.

We will be unable to proceed with next steps for OMONTYS without amendment of our collaboration arrangement with Takeda and the cooperation and support of Takeda in the U.S. If we fail to successfully renegotiate our arrangement or otherwise maintain our existing collaboration with Takeda, such termination would have a material adverse effect on our business and operations and our ability to meet our obligations and may result in our having to cease operations.

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The maintenance and successful performance of our strategic collaboration with Takeda for OMONTYS is an important part of our business and operations, in particular with respect to the OMONTYS recall and investigation. Our collaboration with Takeda is extremely complex and we both have obligations to the FDA and one another with respect to the manufacture, development and approval of OMONTYS, including a sharing of the costs associated with the collaboration which have been significantly impacted by the recall of product and related write-offs of assets and third party commitments. The complexity of our collaboration creates significant risk and uncertainty as to how and when we might be in position to address the safety concerns of OMONTYS that resulted in our product recall. In addition, as our cost-sharing arrangement with Takeda proceeds, without significant renegotiation and support from Takeda, we may be unable to continue in the collaboration which may result in our having to cease operations.

Moreover, Takeda has the ability to terminate our collaboration upon an uncured material breach by us or even in the absence of a material breach with six months notice. Currently, Takeda could terminate either or both of our collaboration agreements, which termination in the U.S. would have a material adverse effect on OMONTYS and our business and operations. In the past, events such as the suspension of the OMONTYS oncology program, the impact of the Phase 3 results on the renal program particularly on the non-dialysis indication, and the decreased market opportunity for ESAs increase the possibility that Takeda may elect to terminate the collaboration or limit the resources Takeda is willing to commit to OMONTYS. The safety concerns with OMONTYS combined with the recent U.S. recall may negatively impact the EMA decision and Takeda's view of the collaboration and its overall commitment to OMONTYS, including in the U.S., our major market opportunity.

Under our collaboration, Takeda currently provides funding and performs important functions, including contracting, pricing, accounting for the collaboration revenue and profit equalization and conducting manufacturing activities, all of which are essential to our continuation as a going concern in the near-term. Even in the absence of termination by Takeda, the significant resources and commitment that may be required to successfully address OMONTYS safety concerns with the FDA and to reintroduce and commercialize OMONTYS in the U.S. may result in limited commercial opportunity, and Takeda's failure to provide funding or timely cooperate in our investigation of the causes of the safety concerns with OMONTYS would have a significant adverse effect on our efforts and our business.

We are currently subject to securities class action litigation and derivative litigation and may be subject to similar or other litigation such as products liability litigation in the future.

We and certain of our officers as well as Takeda Pharmaceutical Company Limited, Takeda Pharmaceuticals U.S.A., Inc. and Takeda Global Research & Development Center, Inc. have been named defendants in two lawsuits filed in February 2013 in the United States District Court for the Northern District of California, brought on behalf of stockholders of the company that alleges violations of the Securities Exchange Act of 1934 in connection with allegedly false and misleading statements made by the defendants regarding our business practices, financial projections and other disclosures between December 8, 2011 and February 22, 2013, or the Class Period. The plaintiffs seek to represent a class comprised of purchasers of our common stock during the Class Period and seek damages, costs and expenses and such other relief as determined by the Court.

In addition, in March 2013, a derivative lawsuit was filed purportedly on behalf of the company in California Superior Court for the County of Santa Clara naming certain of our officers and directors as defendants. The lawsuit alleges that certain of our officers and directors breached their fiduciary duties related to the clinical trials for OMONTYS and for representations regarding our business health, which was tied to the success of OMONTYS. The lawsuit also asserts claims for unjust enrichment and corporate waste.

While we believe we have meritorious defenses and intend to defend these lawsuits vigorously, we cannot predict the outcome of these lawsuits. We believe that there may be additional suits or proceedings brought in the future. Monitoring and defending against legal actions, whether or not meritorious, is time-consuming for our management and detracts from our ability to fully focus our internal resources on our business activities and we cannot predict how long it may take to resolve these matters. In addition, legal fees and costs incurred in connection with such activities may be significant and we could, in the future, be subject to judgments or enter into settlements of claims for significant monetary damages. A decision adverse to our interests on these actions or resulting from these matters could result in the payment of substantial damages and could have a material adverse effect on our cash flow, results of operations and financial position.

Likewise, if additional product liability lawsuits are brought against us for injuries or deaths due to patients' adverse reactions to OMONTYS, we may be subject to additional liability. ~~In any event, a potential product liability lawsuit would require significant financial and management resources.~~ Regardless of the outcome, product liability claims may result in injury to our reputation, withdrawal of clinical trial participants, significant costs, diversion of management's attention and resources, substantial monetary awards, loss of revenue, and additional distractions from our efforts to address safety concerns that may allow us to reintroduce OMONTYS. Our inability to obtain and retain sufficient product liability insurance at an acceptable cost to protect against potential product liability claims could prevent or inhibit the reintroduction of OMONTYS.

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resources, substantial monetary awards, loss of revenue, and additional distractions from our efforts to address safety concerns that may allow us to reintroduce OMONTYS. Our inability to obtain and retain sufficient product liability insurance at an acceptable cost to protect against potential product liability claims could prevent or inhibit the reintroduction of OMONTYS.

With respect to any litigation, our insurance may not reimburse us or may not be sufficient to reimburse us for the expenses or losses we may suffer in contesting and concluding such lawsuits. Substantial litigation costs or an adverse result in any litigation may adversely impact our business, operating results or financial condition.

Our ~~success~~ability ~~depends~~to onobtain ~~our~~potential ~~ability~~royalties ~~with~~and further milestone payments from Takeda todepends ~~effectively~~solely ~~and~~on ~~profitably~~Takeda's ~~commercialize~~efforts ~~OMONTYS,~~to ~~when~~complete the investigation and, if wefeasible, to reintroduce OMONTYS.

Our ~~success~~ability to obtain potential royalties and milestones from OMONTYS depends on ~~our~~Takeda's ~~ability~~efforts ~~with~~to ~~Takeda~~complete the investigation and, if feasible, to reintroduce ~~OMONTYS~~the product and effectively and profitably commercialize ~~OMONTYS~~it when and if weit ~~reintroduce~~is ~~OMONTYS~~reintroduced. There is no assurance that weTakeda can identify and address the underlying cause of the serious hypersensitivity reactions ~~described under the caption “OMONTYS Voluntary Recall” in “Item 1~~.~~Business” of this Annual Report on Form 10-K.~~ If weTakeda ~~fail~~fails to demonstrate the safety of OMONTYS, weTakeda will not be able to reintroduce ~~OMONTYS~~the product and ~~our~~we ~~business~~ will not be ~~materially~~able ~~and~~to ~~adversely~~obtain ~~affected~~any potential royalties or milestones from the product. When and if weTakeda ~~reintroduce~~reintroduces OMONTYS, our success will depend on ~~our~~Takeda's ability to:

• create market demand for OMONTYS through ~~our~~ education, marketing and sales activities, ~~as well as through our co-promotion agreement with Takeda Pharmaceutical Company Limited, or Takeda,~~ including ~~our~~the ability to establish or demonstrate the safety of ~~OMONTYS~~the product;

• ~~re-~~build a qualified commercial and medical affairs organization and field force;


•	achieve market acceptance and generate product sales through Takeda's execution of agreements with the major operators of dialysis clinics on commercially reasonable terms;


•	support the efforts of dialysis clinics to safely and effectively administer OMONTYS to dialysis patients on a different treatment plan than for the other approved erythropoiesis stimulating agents, or ESAs;

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•	receive adequate levels of reimbursement from third-party payors, including government healthcare programs such as Medicare and Medicaid and private insurance programs;


•	comply with the post-marketing requirements established by the FDA, including the Risk Evaluation and Mitigation Strategy, or REMS, and any other requirements established by the FDA in the future;


•	comply with other healthcare regulatory requirements;


•	ensure that the Active Pharmaceutical Ingredient, or API, for OMONTYS and the finished product are manufactured in sufficient quantities and in compliance with requirements of the FDA and similar foreign regulatory agencies and with an acceptable quality and pricing level in order to meet commercial demand; and

• ensure that the entire supply chain for OMONTYS - from API to finished product - efficiently and consistently delivers OMONTYS to ~~our~~ customers.

When and if weTakeda ~~are~~reintroduces ~~able to reintroduce~~ OMONTYS, which is highly uncertain, it will be even more challenging for usTakeda to accomplish these activities in view of the recall and related safety concerns particularly due to the long-term experience with currently marketed products and negative perceptions of OMONTYS' safety. If weTakeda ~~are~~is unable to successfully reintroduce and commercialize OMONTYS, then we will not ~~receive~~obtain any ~~sales~~potential ~~revenue~~royalties or milestones from the product, which will have a material adverse impact on our business and our prospects.

Even if weTakeda ~~are~~is able to reintroduce OMONTYS, weTakeda may not be able to commercialize ~~OMONTYS~~the product successfully.

If weTakeda ~~are~~is able to reintroduce OMONTYS, weTakeda must have, or build, internal sales, marketing, medical affairs, contracting, reimbursement and distribution capabilities~~. If~~ wewith ~~are~~the ~~not~~training ~~successful in re-building a commercial~~ and ~~medical~~experience ~~affairs~~necessary ~~organization,~~to ~~then~~commercialize wethe ~~will~~product ~~have difficulty commercializing OMONTYS when and if it is reintroduced, which would adversely affect our business and financial condition~~successfully. If weTakeda ~~are~~is unable to ~~successfully~~ address these ~~responsibilities~~capabilities ~~ourselves~~internally, then weTakeda may need to identify third-party providers to support these efforts, which may lead to delays and additional costs as well as potential confusion to ~~our~~ customers of OMONTYS. ToIn addition, to the extent that weTakeda ~~enter~~enters into ~~additional~~ co-promotion or other arrangements with respect to OMONTYS, any revenues Takeda receives from the product will depend upon the efforts of both parties, which may not be successful and will be only partially in Takeda's control. These factors may hinder Takeda's ability to commercialize OMONTYS successfully when and if it is reintroduced, which would adversely affect our ability to obtain potential royalties or milestones from the product.

16Even if Takeda is able to reintroduce OMONTYS, Takeda would need to attain significant market acceptance for the product among physicians, patients, health care payors, and the major operators of dialysis clinics, and Takeda would need to reach a long-term agreement with either or both of the largest operators of dialysis clinics.

Until the approval of OMONTYS, only EPOGEN and Aranesp, the ESAs of Amgen, Inc., or Amgen, have been used for the treatment of anemia due to chronic kidney disease in adult patients on dialysis in the U.S. This dialysis market is highly established and concentrated, with EPOGEN and Aranesp serving a significant majority of all dialysis patients on Medicare. These two products are the current standard of care, and it may be difficult to encourage healthcare providers to consider OMONTYS, should it be reintroduced, as an alternative to these products with which they and their patients have a longstanding relationship. Physicians, who make the ultimate decision to prescribe a product, may not prescribe OMONTYS, in which case Takeda's ability to sell the product would be adversely impacted. Similarly, dialysis clinics using EPOGEN or Aranesp could incur substantial expense in administration and training if they were to convert to OMONTYS. Finally, healthcare providers may not receive adequate levels of reimbursement for OMONTYS from third-party payors, including government healthcare programs such as Medicare and Medicaid and private insurance programs. Some or all of these factors may hinder Takeda's efforts to attain significant market acceptance of OMONTYS should it be reintroduced, which would pose a risk to our ability to obtain potential royalties or milestones from the product.

Even if Takeda is able to reintroduce and achieve market acceptance of OMONTYS, if Takeda is unable to reach a long-term supply agreement with either or both of the largest operators of dialysis clinics in the U.S, Fresenius Medical Care North America and DaVita, Inc., or Fresenius and DaVita, respectively, on favorable terms or on a timely basis, then the revenue opportunity for OMONTYS could be significantly reduced. Takeda may not be able to reach a long-term supply agreement with either Fresenius or DaVita because both entered into a long-term supply agreement with Amgen that began in January 2012. In particular, Fresenius entered into a “multi-year” agreement with Amgen whereby Amgen would supply EPOGEN on a “non-exclusive” basis to Fresenius, and DaVita entered into a seven-year agreement with Amgen whereby Amgen would supply EPOGEN to meet at least 90% of DaVita's requirements for ESAs used in providing dialysis services in the U.S. The specific terms of the Amgen-Fresenius agreement and the Amgen-DaVita agreement have not been publicly

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~~revenues~~disclosed, and we ~~receive~~cannot ~~will~~predict ~~depend~~how ~~upon~~these ~~the~~agreements ~~efforts~~may ofimpact ~~both~~the ~~parties,~~commercial ~~which~~opportunity ~~may~~for ~~not~~OMONTYS should it be ~~successful~~reintroduced. But ~~and~~these ~~are~~agreements ~~only~~may ~~partially~~limit inthe ~~our~~market ~~control. Our~~opportunity for the product ~~revenues~~and ~~would~~adversely ~~likely~~impact beour ~~lower~~ability ~~than~~to ifobtain wepotential ~~marketed~~royalties ~~and~~or ~~sold~~milestones ~~our~~from ~~products~~the ~~directly~~product.

~~Even~~The ifopportunity ~~we are able~~ to reintroduce OMONTYS, weis ~~would~~highly ~~need~~uncertain toand ~~attain~~challenging ~~significant~~as ~~market~~a ~~acceptance~~result ~~for~~of the ~~product~~negative ~~among~~perception ~~physicians,~~of ~~patients, health care payors, and~~ the ~~major~~safety ~~operators~~ of ~~dialysis~~the ~~clinics,~~product and ~~we would need to reach a long~~erythropoiesis-~~term~~stimulating ~~agreement~~agents, ~~with either~~ or ~~both~~ESAs ofas ~~the~~a ~~largest operators of dialysis clinics~~class.

~~Until~~ The ~~the~~safety ~~approval~~concerns ofresulting ~~OMONTYS, only EPOGEN and Aranesp, the ESAs of our competitor Amgen, Inc., or Amgen, have been used for the treatment of anemia due to chronic kidney disease~~ in ~~adult patients on dialysis in~~ the ~~U.S. This~~OMONTYS ~~dialysis~~recall ~~market is highly established~~ and ~~concentrated, with EPOGEN and Aranesp serving a significant majority of all dialysis patients on Medicare. These two products are~~ the ~~current~~safety ~~standard~~concerns offor ~~care,~~ESAs ~~and it may be difficult to encourage healthcare providers to consider OMONTYS, should it be reintroduced,~~ as ~~an alternative to these products with which they and their patients have~~ a ~~longstanding~~class ~~relationship. Physicians,~~may ~~who~~ make ~~the~~it ~~ultimate~~challenging ~~decision~~for toTakeda ~~prescribe a product, may not prescribe OMONTYS, in which case our ability~~ to ~~sell~~reintroduce ~~the product would be adversely impacted. Similarly, dialysis clinics using EPOGEN or Aranesp could incur substantial expense in administration and training if they were to convert to~~ OMONTYS~~. Finally,~~ ~~healthcare providers may not receive adequate levels of reimbursement for OMONTYS from third-party payors, including government healthcare programs such as Medicare~~ and ~~Medicaid and private insurance programs. Some or all of these factors~~ may ~~hinder~~significantly ~~our~~reduce ~~efforts~~the topotential ~~attain significant~~ market ~~acceptance of OMONTYS should it be reintroduced, which would pose a risk to our ability to obtain revenues or favorable margins~~ for the product. For example:

Even if we are able to reintroduce and achieve market acceptance of OMONTYS, if we are unable to reach a long-term supply agreement with either or both of the largest operators of dialysis clinics in the U.S, Fresenius Medical Care North America and DaVita, Inc. or Fresenius and DaVita, respectively, on favorable terms or on a timely basis, then the revenue opportunity for OMONTYS could be significantly reduced. We may not be able to reach a long-term supply agreement with either Fresenius or DaVita because both entered into a long-term supply agreement with Amgen that began in January 2012. In particular, Fresenius entered into a “multi-year” agreement with Amgen whereby Amgen would supply EPOGEN on a “non-exclusive” basis to Fresenius, and DaVita entered into a seven-year agreement with Amgen whereby Amgen would supply EPOGEN to meet at least 90% of DaVita's requirements for ESAs used in providing dialysis services in the U.S. The specific terms of the Amgen-Fresenius agreement and the Amgen-DaVita agreement have not been publicly disclosed, and we cannot predict how these agreements may impact the commercial opportunity for OMONTYS should it be reintroduced. But these agreements may limit the market opportunity for the product and adversely impact our ability to generate product sales.

In July 2012, Fresenius entered into a short-term supply agreement with Takeda Pharmaceuticals America, Inc., or TPA, a subsidiary of Takeda, whereby TPA supplied OMONTYS to Fresenius for use in certain U.S. dialysis clinics within its organization. On February 13, 2013, Fresenius communicated that it had accumulated experience with OMONTYS in more than 56,600 administrations in over 18,000 patients in its dialysis facilities and that it had decided to pause further expansion of its OMONTYS pilot program. Fresenius indicated that it would analyze the full set of efficacy and safety profile information regarding OMONTYS and that the current scale of their experience with use of the product was adequate to complete this analysis. Even if we are able to successfully address the recent safety concerns for OMONTYS with the FDA, we believe it may be more challenging to continue with or expand upon the short-term supply agreement with Fresenius in the near term. In any event, Amgen's long-term supply agreements with DaVita and Fresenius and the potential introduction of Mircera and biosimilars may limit the market opportunity for OMONTYS and adversely impact our ability to generate product sales should we reintroduce the product.

The opportunity to reintroduce OMONTYS is highly uncertain and challenging as a result of the negative perception of the safety of OMONTYS.

The safety concerns resulting in the recent OMONTYS recall and the safety concerns for ESAs as a class may make it challenging to identify and rectify the causes of the safety concerns to the satisfaction of the FDA and may significantly reduce the market for OMONTYS if and when it is reintroduced For example:

•

In 2007, as a result of concerns associated with administering ESAs to target higher hemoglobin levels, the FDA required that revised warnings, including boxed warnings, be added to the labels of currently marketed ESAs advising physicians to monitor hemoglobin levels and to use the lowest dose of ESA to increase the hemoglobin concentration to the lowest level sufficient to avoid the need for red blood cell transfusions.

• In late 2009, Amgen announced the results from the Trial to Reduce Cardiovascular Endpoints with Aranesp Therapy, or TREAT, its large, randomized, double-blind, placebo-controlled Phase 3 study of patients with chronic kidney disease (not requiring dialysis), anemia and type-2 diabetes. In this study, Aranesp was used to treat anemia to a target hemoglobin of 13 g/dL, which was higher than the 10 g/dL - 12 g/dL range previously approved by the FDA in the label. Study results reportedly failed to show benefit compared to the control group with regard to composite of time to all-cause mortality or cardiovascular morbidity (including heart failure, heart attack, stroke, or hospitalization for myocardial ischemia) and a composite of time to all-cause mortality or chronic renal replacement. In addition, higher rates of stroke were reported among patients treated with Aranesp compared to the control group. Finally, among a subgroup of patients with a history of cancer at baseline, a statistically significant increase in deaths from cancer was observed in the Aranesp-treated patients compared to placebo-treated patients.

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treat anemia to a target hemoglobin of 13 g/dL, which was higher than the 10 g/dL - 12 g/dL range previously approved by the FDA in the label. Study results reportedly failed to show benefit compared to the control group with regard to composite of time to all-cause mortality or cardiovascular morbidity (including heart failure, heart attack, stroke, or hospitalization for myocardial ischemia) and a composite of time to all-cause mortality or chronic renal replacement. In addition, higher rates of stroke were reported among patients treated with Aranesp compared to the control group. Finally, among a subgroup of patients with a history of cancer at baseline, a statistically significant increase in deaths from cancer was observed in the Aranesp-treated patients compared to placebo-treated patients.

•

In January 2010, FDA officials published an editorial in the New England Journal of Medicine noting that a number of randomized trials, including TREAT, had attempted to show that using ESAs to raise hemoglobin concentrations to higher targets improves clinical outcomes but rather suggested the opposite. Accordingly, the article indicated that more conservative hemoglobin targets (well below 12 g/dL), more frequent hemoglobin monitoring, and more cautious dosing, should be evaluated.


•	In February 2010, the FDA announced that ESAs must be prescribed and used under a REMS to ensure the safe use of the drugs. As part of the REMS, a medication guide explaining the risks and benefits of ESAs must be provided to all patients receiving ESAs for all indications, and the manufacturer has reporting and monitoring obligations to ensure compliance.

•

In June 2011, the FDA cited increased risks of cardiovascular events as a basis for more conservative dosing guidelines for use of ESAs in chronic kidney disease and announced related changes to ESA labeling. The FDA removed the prior target range of 10-12 g/dL and while separately issuing guidance for non-dialysis patients, the FDA recommended that dialysis patients initiate treatment when the hemoglobin is less than 10 g/dL and to reduce or interrupt dosing if hemoglobin level approaches or exceeds 11 g/dL. The FDA also required Amgen to conduct additional clinical trials to explore dosing strategies, including in dialysis patients to minimize hemoglobin variability, rates of change and excursions.


•	In February 2013, in connection with the recall, the FDA announced that due to the severity of the public health risk, the FDA wanted to be certain that health care providers stop using OMONTYS and that it would investigate products and facilities associated with the recall and would provide updates.

The controversy surrounding ESAs and FDA safety concerns has, and may, further negatively affect OMONTYS when and if it is reintroduced. In addition, recent and future FDA actions represent additional challenges to the market for ESAs as a class and may affect the timing or costs associated with implementing a solution to address the ~~cause~~safety ofconcerns ~~patients'~~resulting ~~hypersensitivity~~in ~~reactions~~the to OMONTYS ~~when~~recall ~~and~~to ifthe asatisfaction ~~cause~~of ~~is available that is satisfactory to~~ the FDA. We cannot predict what additional actions, if any, the FDA may take, which may include additional label restrictions, the use of informed consents, further lowering or removal of target hemoglobin levels, or even the removal of indications from the label. Further, regardless of whether or not the FDA takes additional action, the Centers for Medicare and Medicaid Services, or CMS, and other third-party payors may still decide separately to discontinue or limit coverage or lower reimbursement as CMS has recently adopted changes and continues to evaluate coverage and ~~reimbursement policy for ESAs as class. Any of these factors could significantly delay or negatively impact the commercialization of OMONTYS when and if we reintroduce it.~~

In addition, any negative perception of the safety of OMONTYS relative to other ESAs as a result of our Phase 3 clinical results could significantly reduce the market opportunity for our product when and if we reintroduce it. Specifically, in June 2010, we announced preliminary top-line results from the OMONTYS Phase 3 clinical program for the treatment of patients with anemia associated with chronic kidney disease. Our Phase 3 clinical program included four open-label, randomized controlled clinical trials: PEARL 1 and PEARL 2 conducted in non-dialysis patients and EMERALD 1 and EMERALD 2 conducted in dialysis patients. Analysis of efficacy and safety for all of the Phase 3 trials were based primarily on assessments of non-inferiority to the comparator drugs. While OMONTYS met the statistical criterion for non-inferiority for the assessment of safety for the cardiovascular composite safety endpoint, or CSE, which was composed of death, stroke, myocardial infarction, congestive heart failure, unstable angina and arrhythmia from a pooled safety database across the four Phase 3 trials, some differences were observed when secondary analyses were conducted, including a difference in a subgroup analysis conducted in the PEARL trials where the frequency of CSE events was higher in the OMONTYS group relative to the comparator in non-dialysis patients. Since OMONTYS was launched, over 25,000 patients have been treated with OMONTYS. Serious hypersensitivity reactions, including anaphylaxis, which can be life-threatening or fatal, have been recently reported as described under the caption “OMONTYS Voluntary Recall” under “Item 1. Business” of this Annual Report on Form 10-K. On February 23, 2013, we and Takeda announced a nationwide voluntary recall of OMONTYS and suspended the promotional activities and marketing of OMONTYS. This has severely harmed our business and future financial 16

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~~results~~reimbursement policy for ESAs as class. Any ~~negative~~of ~~perception~~these factors could significantly delay or negatively impact the commercialization of OMONTYS' ~~safety~~when ~~relative~~and toif ~~other~~it ~~ESAs~~is ~~could~~reintroduced ~~further~~by ~~significantly~~Takeda, ~~limit~~which ~~any~~would ~~potential~~significantly ~~opportunity~~affect ~~for~~our usability to ~~reintroduce~~obtain potential royalties and ~~successfully~~milestones ~~commercialize~~from ~~OMONTYS.~~the product

In addition, any negative perception of the safety of OMONTYS relative to other ESAs as a result of our Phase 3 clinical results could significantly reduce the market opportunity for the product when and if it is reintroduced by Takeda. Specifically, in June 2010, we announced preliminary top-line results from the OMONTYS Phase 3 clinical program for the treatment of patients with anemia associated with chronic kidney disease. Our Phase 3 clinical program included four open-label, randomized controlled clinical trials: PEARL 1 and PEARL 2 conducted in non-dialysis patients and EMERALD 1 and EMERALD 2 conducted in dialysis patients. Analysis of efficacy and safety for all of the Phase 3 trials were based primarily on assessments of non-inferiority to the comparator drugs. While OMONTYS met the statistical criterion for non-inferiority for the assessment of safety for the cardiovascular composite safety endpoint, or CSE, which was composed of death, stroke, myocardial infarction, congestive heart failure, unstable angina and arrhythmia from a pooled safety database across the four Phase 3 trials, some differences were observed when secondary analyses were conducted, including a difference in a subgroup analysis conducted in the PEARL trials where the frequency of CSE events was higher in the OMONTYS group relative to the comparator in non-dialysis patients. Since OMONTYS was launched, over 25,000 patients have been treated with the product. Serious hypersensitivity reactions, including anaphylaxis, which can be life-threatening or fatal, have been reported. As a result, on February 23, 2013, we and Takeda announced a nationwide voluntary recall of OMONTYS and suspended the promotional activities and marketing of the product. This has severely harmed our business and future financial results. Any negative perception of OMONTYS' safety relative to other ESAs could further significantly limit any potential opportunity for Takeda to reintroduce and successfully commercialize the product, which would significantly limit any potential opportunity for us to obtain potential royalties and milestones from the product.

Finally, any negative perception of the safety of OMONTYS relative to other ESAs as a result of any new medical data or product quality issues that suggest new risks or side effects, or increase concern over previously identified risks or side effects would significantly negatively impact the commercial potential as well as any possible reintroduction of OMONTYS.

WeTakeda ~~have~~has continuing regulatory obligations with respect to OMONTYS and FDA approval remains subject to certain post-marketing requirements that could significantly increase costs or delay or limit ~~our~~Takeda's ability to successfully commercialize the product when and if it is reintroduced. If results, data or information with respect to ~~our~~Takeda's continuing obligations are negative or weTakeda ~~are~~is unable to fulfill ~~our~~its continuing obligations to regulatory authorities or ~~our~~its post-marketing requirements, there may be changes to ~~our~~the product label or weTakeda may be required to withdraw the product from the market.

The FDA approved OMONTYS subject to certain post-marketing requirements. ~~For~~An ~~example, we are required to conduct an~~ observational study and a randomized controlled trial tomust be ~~completed~~conducted with final reports submitted in 2018 and 2019, respectively, to evaluate cardiovascular safety and assess safety of long-term use in adult patients on dialysis. We Pediatric ~~are~~studies ~~also~~must ~~required~~be toconducted ~~initiate pediatric studies~~ with target dates for completion between 2016 and 2027. InA ~~addition,~~REMS wemust ~~are~~be ~~required to comply with a REMS~~implemented, which includes a requirement to send “Dear Healthcare Provider” letters to nephrology healthcare providers informing them that OMONTYS is not indicated in patients with chronic kidney disease not on dialysis.

Even if weTakeda ~~are~~is able to address the safety concerns resulting in ~~our~~the recall of OMONTYS to the satisfaction of the FDA, maintaining regulatory approval for ~~OMONTYS~~the product will be increasingly difficult. If weTakeda ~~are~~is unable to fulfill the requirements of regulatory authorities or ~~our~~the post-marketing requirements or to the extent there are other unfavorable results, data or other information arising therefrom, then there may be limitations imposed on ~~our~~the product label or weTakeda may be required to permanently withdraw the product from the market.

We Competition ~~have~~in ~~relied~~the onpharmaceutical ~~numerous~~industry ~~third~~is ~~parties~~intense. The toOMONTYS ~~conduct~~recall ~~and~~means ~~complete~~that ~~our~~the ~~development~~product ~~program for OMONTYS, and we~~ will ~~continue~~have to ~~rely~~overcome onsignificant ~~third~~competitive ~~parties~~issues relative to ~~maintain~~other ~~approval~~approved ofESAs on the ~~product~~market.

~~Due~~When ~~to the size~~ and ~~limited~~if ~~experience~~OMONTYS ofis ~~our organization~~reintroduced, weTakeda ~~have~~will ~~relied~~face ~~heavily~~competition onfrom ~~third~~established ~~parties~~pharmaceutical toand ~~assist~~biotechnology uscompanies, in ~~managing,~~particular ~~monitoring~~companies ~~and~~that ~~otherwise conducting our clinical trials. Even though we~~ have ~~completed~~an ~~our Phase 3 clinical program and OMONTYS was~~ approved byESA ~~the~~on ~~FDA, we will continue to require~~ the ~~assistance of third parties in the future, particularly with respect to completing our post-marketing requirements~~market. ~~For~~ The ~~example,~~commercial ~~FDA~~opportunity ~~and foreign regulatory agencies require us to comply with regulations and standards, commonly referred to as good clinical practices,~~ for ~~conducting,~~OMONTYS ~~recording~~will ~~and~~be ~~reporting~~reduced ~~the~~or ~~results~~eliminated ofif ~~clinical~~competitors ~~trials~~develop ~~to assure that the data~~ and ~~results~~commercialize ~~are~~products ~~credible and accurate and~~ that ~~the trial participants~~ are ~~adequately~~more ~~protected. Our reliance on third parties in connection with conducting our post-marketing trials does not relieve us of these responsibilities and requirements~~effective, ~~and~~have ~~regulatory~~fewer ~~authorities~~side ~~may~~effects ~~find remediation efforts by us~~ or ~~such~~are ~~third~~less ~~parties~~expensive ~~insufficient. In~~than ~~addition, we have had significant difficulties obtaining necessary and quality third-party assistance~~OMONTYS. WeThe ~~continue~~OMONTYS torecall ~~compete with larger~~ and ~~other~~the ~~companies~~uncertainty ~~for~~of whether the ~~attention~~product ~~and~~will ~~assistance~~be ofavailable ~~these~~on ~~third~~the ~~parties. If~~market weat ~~are~~all ~~unsuccessful~~may inmean ~~obtaining~~that the ~~needed~~product ~~assistance~~will onbe ~~acceptable~~at ~~terms,~~a wesignificant ~~will~~disadvantage ~~have~~upon ~~difficulty~~the ~~commercializing~~entry ~~OMONTYS~~of ~~and~~competing ~~completing our post-marketing requirements~~products.

~~Competition~~When inand ~~the~~if ~~pharmaceutical~~OMONTYS ~~industry~~ is ~~intense. Our~~reintroduced, ~~recent~~we ~~product~~anticipate ~~recall means~~ that ~~OMONTYS~~it will ~~have~~compete towith ~~overcome~~EPOGEN ~~significant~~and ~~competitive~~potentially ~~issues~~Aranesp, ~~relative~~which toare ~~other~~both ~~approved~~marketed ~~ESAs~~by onAmgen, and NeoRecormon and Mircera, which are currently marketed outside the ~~market~~U.S. by Roche.

We face competition from established pharmaceutical and biotechnology companies, in particular companies that have an approved ESA on the market. Our commercial opportunity will be reduced or eliminated if our competitors develop and commercialize products that are more effective, have fewer side effects or are less expensive than OMONTYS. Our recent setback with the OMONTYS recall and the uncertainty of whether OMONTYS will be available on the market at all may mean that OMONTYS will be at a significant disadvantage upon the entry of competing products.17

When and if OMONTYS is reintroduced, we anticipate that it will compete with EPOGEN and potentially Aranesp, which are both marketed by Amgen, and NeoRecormon and Mircera, which are currently marketed outside the U.S. by Roche. Mircera reportedly has greater plasma stability and is longer acting than any rEPO product that was on the market in the U.S. prior to OMONTYS. As a result of the patent litigation between Roche and Amgen, Mircera was found to infringe several U.S. patents owned by Amgen and was enjoined from being sold in the U.S. until the expiration of these patents in mid-2014 under a limited license. If Mircera enters the U.S. market, we believe it will be in direct competition with OMONTYS, if we are able to reintroduce the product, because of Mircera's ability to be long-acting; therefore, it could potentially limit the market for OMONTYS.

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~~The~~Mircera ~~introduction~~reportedly ofhas ~~biosimilars~~greater ~~into~~plasma ~~the~~stability ~~ESA~~and is longer acting than any rEPO product that was on the market ~~could~~in ~~also~~the ~~prove~~U.S. prior to beOMONTYS. As a ~~significant~~result ~~threat~~of ifthe patent litigation between Roche and ~~when~~Amgen, weMircera ~~reintroduce~~was ~~OMONTYS~~found asto ~~biosimilars~~infringe ~~could~~several ~~not~~U.S. ~~only~~patents ~~limit~~owned by Amgen and was enjoined from being sold in the U.S. until the expiration of these patents in mid-2014 under a limited license. If Mircera enters the U.S. market, ~~for~~we believe it will be in direct competition with OMONTYS, if Takeda is able to reintroduce the product, ~~but~~because ~~could~~of ~~also~~Mircera's ~~drive~~ability ~~down~~to be long-acting; therefore, it could potentially limit the ~~price~~market offor ~~ESAs~~OMONTYS.

WeThe ~~may~~introduction ~~also face competition from potential new anemia therapies if and when we reintroduce OMONTYS. There are several product candidates in various stages~~ of ~~active~~biosimilars ~~development~~into ~~for~~the ~~anemia~~ESA ~~indications~~market bycould ~~potential~~also ~~competitors~~prove ~~that~~to ~~may~~be ~~promote~~a ~~the~~significant ~~production~~threat ofwhen ~~naturally-occurring EPO in patients,~~ and ~~some~~if ofTakeda ~~these~~reintroduces ~~product~~OMONTYS ~~candidates may enter the market~~ as ~~early~~biosimilars ascould ~~2015. If~~not ~~these~~only ~~product~~limit ~~candidates enter~~ the market ~~they~~for ~~may~~the ~~be in direct competition with OMONTYS if and when it is reintroduced. In addition~~product, ~~certain~~but ~~companies are developing potential new therapies for renal-related diseases that~~ could ~~reduce~~also ~~ESA~~drive ~~utilization~~down ~~and thus limit~~ the ~~market~~price ~~for~~of ~~OMONTYS if and when it is reintroduced~~ESAs.

~~Most~~Takeda ofmay ~~these~~also ~~competitors~~face ~~have~~competition ~~substantially~~from ~~greater~~potential ~~financial~~new ~~resources~~anemia ~~and~~therapies ~~expertise~~when ~~in obtaining regulatory approvals~~ and ~~marketing~~if ~~approved~~OMONTYS ~~products~~is ~~than we do~~reintroduced. ~~Current~~ There ~~marketers~~are ofseveral ~~ESAs~~product ~~also~~candidates ~~have~~in ~~the~~various ~~ability~~stages ~~to bundle sales~~ of ~~existing~~active ~~ESA~~development ~~products~~for ~~with~~anemia ~~their~~indications ~~other~~by ~~products,~~potential ~~potentially~~competitors ~~disadvantaging~~that ~~OMONTYS,~~may ~~which~~promote wethe ~~anticipate~~production toof ~~sell on a stand~~naturally-~~alone~~occurring ~~basis~~EPO ~~when~~in patients, and ifsome weof ~~reintroduce~~these ~~it. Established~~product ~~pharmaceutical~~candidates ~~and large biotechnology companies~~ may ~~invest~~enter ~~heavily~~the tomarket ~~discover~~as ~~and~~early ~~develop~~as ~~novel~~2015. If ~~compounds~~these orproduct ~~drug~~candidates ~~delivery~~enter ~~technology~~the ~~that~~market ~~could~~they ~~make OMONTYS obsolete. Smaller or early-stage companies~~ may ~~also prove to~~ be ~~significant~~in ~~competitors,~~direct ~~particularly~~competition ~~through strategic partnerships~~ with ~~large~~OMONTYS ~~and~~when ~~established companies. These third parties may compete with us in recruiting~~ and ~~retaining~~if ~~qualified~~it ~~scientific~~is ~~and~~reintroduced. In ~~management personnel~~addition, ~~establishing~~certain ~~clinical~~companies ~~trial~~are ~~sites~~developing ~~and~~potential ~~patient~~new ~~registration~~therapies for ~~clinical~~renal-related ~~trials,~~diseases asthat ~~well~~could asreduce inESA ~~acquiring~~utilization ~~technologies~~ and ~~technology~~thus ~~licenses~~limit ~~complementary~~the tomarket ~~our~~for ~~programs~~OMONTYS orwhen ~~advantageous to our business. Our competitors may succeed in obtaining patent or other intellectual property protection or discovering, developing~~ and ~~commercializing~~if ~~products~~it ~~before~~is ~~we do~~reintroduced.

When and if weTakeda ~~reintroduce~~reintroduces OMONTYS, the U.S. market opportunity for ~~OMONTYS~~the product may deteriorate significantly after the entry of biosimilars in the U.S.

In March 2010, federal legislation gave the FDA authority to create an abbreviated approval path for biological products that are demonstrated to be “biosimilar” to, or “interchangeable” with, an FDA-approved biological product. In February 2012, the FDA released three draft guidance documents regarding this abbreviated approval path for biosimilar products and the FDA accepted public comments on these documents. A biosimilar product would be a subsequent version of an existing, branded FDA-approved biologic product. The patent for the existing branded product must expire in a given market before biosimilars may enter that market.

The patents for epoetin alfa, a version of recombinant human erythropoietin, or rEPO, expired in 2004 in the European Union, or E.U., and the remaining patents expire from 2012 through 2015 in the U.S. Several biosimilar versions of rEPO are available for sale in the E.U. and biosimilar versions of rEPO are currently being studied in clinical trials in the U.S. For example, in January 2012, Hospira, Inc. announced the beginning of its Phase 3 clinical program for its biosimilar with results anticipated in 2013, and in October 2012, Sandoz announced the beginning of its Phase 3 clinical program for its biosimilar with results anticipated in 2014.

We expect that biosimilars, including rEPO, will be sold at a discount to existing branded products when they are launched in the U.S. as in the E.U. The introduction of biosimilars into the rEPO market in the U.S. could prove to be a significant threat to OMONTYS if they are able to demonstrate biosimilarity to existing rEPO. Biosimilars will constitute additional competition for OMONTYS should it be reintroduced, and are expected to drive down its price and sales volume, which would adversely affect the commercial success of the product and our ~~revenues~~ability to obtain potential royalties or milestones from it.

~~The~~With the amendment of our collaboration, the reintroduction and commercial success of OMONTYS in the U.S. depends inentirely ~~significant part~~ on the efforts of Takeda~~, over which we have limited control in the U~~.~~S. The~~ ~~corporate~~Similarly, ~~governance~~outside ~~structure and division~~ of ~~roles and responsibilities with Takeda under our co-promotion agreement is complex and requires substantial coordination and focus on~~ the ~~part of Takeda to successfully execute our plans. Outside of the~~ U.S. ~~in the Takeda territory~~, we are solely dependent on the efforts and commitments of Takeda, either directly or through third parties, to reintroduce or further commercialize OMONTYS. If our ~~collaborations~~collaboration ~~are~~with ~~unsuccessful,~~Takeda ~~our~~does ~~ability~~not tocontinue, ~~commercialize products through~~ our ~~collaborations,~~ability ~~and~~ to ~~generate~~receive future ~~product~~royalties ~~sales,~~ would be significantly reduced.

Our dependence on Takeda for our global collaboration subjects us to a number of risks, including our ~~ability~~sole toreliance ~~successfully~~on ~~reintroduce~~Takeda ~~and~~to ~~commercialize~~reintroduce OMONTYS in the U.S. and ~~sole reliance on Takeda,~~ either directly or through third parties, to obtain and maintain regulatory approvals and achieve market acceptance of the product inoutside the ~~Takeda territory~~U.S.

20 As a result of the recent amendment to the collaboration with Takeda, Takeda holds an exclusive license to develop and commercialize OMONTYS worldwide. We have no control or influence over Takeda's decision-making as to OMONTYS. If Takeda is unwilling to continue to make further investments of time, resources and fund in OMONTYS, including the completion of the ongoing investigation, which may not be feasible or successful, we may have no recourse and the product may never be reintroduced in the U.S. or approved in any other territories, including in Europe and Japan. As a consequence, any progress and commercial success in any territory is dependent solely on Takeda's efforts and commitment to the program, which may be substantially reduced as a result of the recall. Takeda's decision in December 2011 not to commercialize the product in Japan and the delay or failure to secure a third party to commercialize the product in a timely manner may

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~~Under~~significantly ~~our~~reduce ~~collaboration with Takeda, we have co-commercialized OMONTYS in~~ the ~~U.S.,~~commercial ~~and~~opportunity ~~will further co-commercialize the product~~ in ~~the~~that ~~U.S.~~territory when and if itTakeda isreintroduces ~~reintroduced~~OMONTYS. ~~Because~~In weaddition, ~~share~~Takeda ~~responsibility~~may ~~with~~delay, ~~Takeda~~reduce ~~for~~or ~~commercialization~~terminate ~~activities~~investigation and reintroduction efforts in the U.S., ~~which involves a complex corporate governance structure~~ and ~~division~~development ofefforts ~~roles~~relating ~~and~~to ~~responsibilities,~~ the ~~conduct~~product ~~and~~elsewhere, ~~success~~independently ofdevelop ~~the~~products ~~OMONTYS~~that ~~program~~compete iswith ~~substantially dependent on~~ the ~~efforts~~product, ~~of Takeda over which we have limited~~ or nofail ~~control. Further,~~to ascommit ~~Takeda~~sufficient ~~has~~resources ~~significant~~to ~~rights,~~the ~~responsibilities~~marketing and ~~decision-making~~distribution ~~authority over commercialization~~ of ~~OMONTYS in~~ the Uproduct.~~S.,~~ Competing ~~including~~products ~~final~~or ~~decision-making authority with respect to pricing~~programs, ~~contracting~~either ~~and~~developed ~~distribution~~by ~~activities, any failure of~~ Takeda or to ~~act~~which inour acollaboration ~~timely~~partners ~~manner~~have orrights ~~make adequate investments of funds~~ or ~~resources~~acquire ~~may~~in ~~delay~~ the ~~reintroduction and further commercialization of OMONTYS~~future, ~~which~~ may result in ~~a negative impact on~~ our ~~planned~~partners' ~~timelines,~~withdrawal ~~require us to contribute more resources to reintroduce and successfully commercialize OMONTYS and decrease the likelihood~~ of ~~reintroduction~~support ~~and commercial success~~ for ~~OMONTYS in~~ the Uproduct.S.

~~Outside~~Takeda's ofobligations to exercise diligence under the ~~U.S.~~collaboration, ~~Takeda~~as ~~holds~~amended, anare ~~exclusive~~suspended ~~license~~until toafter ~~develop~~approval ~~and~~by ~~commercialize~~the FDA for reintroduction of OMONTYS ~~and~~without ~~has~~additional ~~primary~~investigative, ~~responsibility~~non-clinical ~~for~~or ~~filing~~clinical ~~regulatory~~activities. In ~~submissions~~the ~~and~~event ~~obtaining~~that ~~product~~Takeda ~~approvals~~fails into ~~those~~diligently ~~territories~~pursue the investigation or reintroduce OMONTYS, ~~including~~our incollaboration ~~Europe~~agreement ~~and~~provides ~~Japan. As~~us athe ~~consequence,~~right ~~any~~to ~~progress~~allege ~~and~~breach ~~commercial~~only ~~success~~after FDA approval for reintroduction and in ~~those~~limited ~~territories~~circumstances iswhich ~~dependent~~may ~~solely~~be ondifficult ~~Takeda's~~to ~~efforts~~prove. Even ~~and~~if ~~commitment~~we were to ~~the~~successfully ~~program.~~assert breach, termination of Takeda's ~~decision~~ rights in ~~December~~certain ~~2011~~instances may not provide us with ability to ~~commercialize~~realize ~~the~~any ~~product~~economic value from OMONTYS in ~~Japan~~view ~~and~~of our ongoing restructuring. Further, our ability to enforce the ~~delay~~diligence provisions and establish breach of Takeda's diligence or ~~failure~~other obligations so as to ~~secure~~obtain meaningful recourse within a ~~third~~reasonable ~~party~~timeframe is uncertain. Further, any decision to ~~commercialize~~pursue available remedies including termination would impact the ~~product~~potential insuccess aof ~~timely~~OMONTYS, ~~manner~~and we may ~~significantly~~choose ~~reduce~~not ~~the~~to ~~commercial~~terminate ~~opportunity~~as inwe ~~that~~may ~~territory~~not ~~when~~be ~~and~~able ifto wefind ~~reintroduce~~another ~~OMONTYS. In~~partner ~~addition,~~and ~~Takeda~~any ~~may~~new ~~delay,~~collaboration ~~reduce~~likely orwill ~~terminate~~not ~~development~~provide ~~efforts~~comparable ~~relating~~financial terms to those in our arrangement with Takeda. In the ~~product~~event ~~elsewhere~~of our termination, ~~independently~~this ~~develop~~may ~~products~~require ~~that~~us ~~compete~~to ~~with~~commercialize the product, oron ~~fail~~our toown, ~~commit~~which ~~sufficient~~is ~~resources~~unlikely to be feasible with the ~~marketing~~recent ~~and~~reductions ~~distribution~~in substantially all of ~~the~~our ~~product~~workforce. ~~Competing~~Significant ~~products~~changes orin ~~programs~~Takeda's business strategy, ~~either~~resource ~~developed~~commitment byand ~~Takeda~~the willingness or ability of Takeda to ~~which~~complete ~~our~~its ~~collaboration~~obligations ~~partners~~under ~~have~~our ~~rights~~arrangement orcould ~~acquire~~materially inaffect the ~~future,~~potential ~~may~~success ~~result~~of inthe ~~our~~product, ~~partners'~~including ~~withdrawal~~the reintroduction of ~~support~~OMONTYS ~~for~~when ~~the~~and ~~product~~if it occurs.

InWith the ~~event~~recent ~~that~~amendment ~~Takeda~~of ~~fails to diligently commercialize OMONTYS, our collaboration and co-promotion agreements provide us~~ the ~~right to allege breach and if successfully asserted~~collaboration, ~~terminate our partner's rights in certain instances. However, our ability to enforce the diligence provisions and establish breach of~~ Takeda's ~~diligence~~has orassumed ~~other~~full ~~obligations~~responsibility sofor asmanufacturing ~~to obtain meaningful recourse within a reasonable timeframe is uncertain. Further, any decision to pursue available remedies including termination would impact the potential success~~ of OMONTYS, ~~and~~including wefor ~~may~~API ~~choose~~as ~~not~~well ~~to terminate~~ as wefinished ~~may~~product ~~not be able to find another partner~~ and ~~any~~as ~~new~~a ~~collaboration~~consequence, ~~likely~~we ~~will~~have ~~not~~limited ~~provide~~ability ~~comparable financial terms~~ to ~~those~~control inrisks ~~our~~associated ~~arrangement~~ with ~~Takeda. In~~future ~~the event of our termination, this may require us to commercialize the product on our own, which is likely to result in significant additional expense and delay~~manufacturing. ~~Significant~~ Manufacturing ~~changes in Takeda's business strategy~~difficulties, ~~resource~~disruptions ~~commitment and the willingness~~ or ~~ability~~delays ~~of Takeda to complete its obligations under our arrangement~~ could ~~materially~~delay ~~affect~~reintroduction ~~the potential success~~ of ~~the~~OMONTYS ~~product,~~and have ~~including~~a ~~the~~further ~~reintroductionof~~material ~~OMONTYS~~adverse ~~when~~effect ~~and~~on ifour ~~it occurs~~business.

WeSince ~~have~~the ~~limited~~recall ~~ability to control~~ and ~~influence~~as ~~Takeda~~we inhave ~~its~~transferred ~~strategic~~manufacturing ~~decisions. This~~responsibility isto ~~particularly~~Takeda ~~important~~for ~~should~~OMONTYS, we ~~reintroduce~~plan ~~and further commercialize OMONTYS in the U.S. If Takeda were~~ to ~~breach~~suspend or terminate ~~either~~manufacturing ofactivities ~~our~~to ~~collaboration~~the ~~agreements~~extent orpracticable ~~otherwise~~in ~~inadequately~~order ~~perform or fail~~ to ~~perform~~decrease ~~its~~our ~~obligations~~ongoing ~~thereunder~~manufacturing incosts aand ~~timely manner~~commitments, ~~the~~including ~~reintroduction~~but ~~and~~not ~~commercialization~~limited ofto, ~~OMONTYS~~termination ~~would~~of beorders ~~delayed,~~and ~~terminated~~agreements. These oractions may negatively ~~impacted. Moreover,~~impact ifthe ~~Takeda~~ability ~~fails~~ to ~~successfully~~reintroduce ~~develop and commercialize~~ OMONTYS ~~outside~~as ofTakeda ~~the~~will ~~U.S.,~~need ~~our~~to ~~potential~~separately toestablish ~~generate~~manufacturing ~~future~~contracts ~~revenue~~or incapabilities ~~the~~which ~~Takeda~~may ~~territory~~require ~~would~~significant beeffort ~~significantly~~and ~~reduced~~cause delay.

~~Significant~~Even ~~challenges~~if ~~remain~~Takeda ~~with~~is usable ~~and Takeda~~ to ~~manufacture OMONTYS on a commercial scale should we~~ reintroduce OMONTYS~~. Our dependence upon third parties for manufacture and supply may cause delays in~~, orthe ~~prevent~~OMONTYS usmanufacturing ~~from,~~process ~~successfully~~is ~~reintroducing~~complicated and ~~commercializing~~time ~~OMONTYS~~consuming. InManufacture ~~accordance with the terms~~ of ~~our~~OMONTYS ~~collaboration,~~API ~~Takeda~~involves ~~has~~long ~~responsibility~~lead ~~for manufacture of finished product and as a consequence, we have limited ability to control risks associated with that portion of the manufacturing process~~times. Manufacturing difficulties, disruptions or delays could limit ~~supply~~reintroduction ~~of our product sales~~ and ~~have~~supply aof ~~material~~the ~~adverse effect on our business~~product.

InOMONTYS ~~connection~~is ~~with~~a ~~the~~new ~~recall~~chemical entity and inthe ~~consultation with Takeda, we plan to suspend~~ manufacturing ~~activities~~process tofor ~~the~~commercial ~~extent~~scale ~~practicable~~production ~~pending~~in ~~consideration~~accordance ~~of next steps~~ with ~~OMONTYS. If~~applicable weregulatory ~~are~~guidelines ~~successful~~remains inchallenging ~~identifying the cause of the recent safety concerns~~ and ~~addressing~~as itsuch, wethere ~~and~~are ~~Takeda~~risks ~~will~~associated ~~determine~~with the ~~next~~commercial ~~appropriate~~scale ~~steps~~manufacture toof ~~take~~the ~~with OMONTYS~~API. ~~Prior~~Similar tochallenges ~~such~~exist ~~time,~~for wethe ~~plan~~manufacture toof ~~evaluate~~finished ~~strategies~~product tothat ~~decrease~~must ~~our~~meet ~~ongoing~~a ~~manufacturing~~variety ~~costs~~of ~~and~~regulatory ~~commitments,~~requirements ~~including~~that ~~but~~vary ~~not~~from ~~limited~~country to, ~~termination~~country ~~of orders~~ and ~~agreements,~~continue ~~which may negatively impact our ability~~ to ~~reintroduce OMONTYS~~change. IfAny weof ~~are~~these ~~able~~risks toand ~~reintroduce~~others ~~OMONTYS, we intend to continue to rely on third-party manufacturers to produce API, which~~ may ~~require~~prevent ~~significant~~or ~~effort~~delay ~~and~~Takeda ~~validation~~from ofsuccessfully ~~new~~reintroducing ~~CMOs. While we~~ and ~~Takeda~~commercializing ~~are actively investigating to determine the cause of the recent safety concerns~~OMONTYS, weincluding ~~cannot give any assurances as to whether we can be successful in doing so. Our inability to determine~~ the ~~cause of the recent safety concerns and find and implement a solution to address it may render us unable to reintroduce and manufacture OMONTYS.~~ following:

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Even if we are able to reintroduce OMONTYS, the OMONTYS manufacturing process is complicated and time consuming. Manufacture of OMONTYS API involves long lead times with our CMOs and suppliers. Manufacturing difficulties, disruptions or delays could limit supply of our product. We do not currently have the infrastructure or capability internally to manufacture the OMONTYS needed to conduct our clinical trials or to commercialize the product. We have relied, and will continue to rely, on CMOs to produce our clinical trial materials for the foreseeable future and we expect to continue to rely on CMOs, partners and other third parties to produce sufficient quantities of OMONTYS for all our uses, including commercialization. When and if we reintroduce OMONTYS, if our CMOs or other third parties fail to deliver materials for the manufacture of OMONTYS, or OMONTYS itself, on a timely basis, with sufficient quality and at commercially reasonable prices, and if we fail to find replacement manufacturers or to develop our own manufacturing capabilities, we may have to delay or suspend future clinical trials or otherwise delay or discontinue commercialization or production.

OMONTYS is a new chemical entity and the manufacturing process for commercial scale production in accordance with applicable regulatory guidelines remains challenging and as such, there are risks associated with the commercial scale manufacture of the API. Similar challenges exist for the manufacture of finished product that must meet a variety of regulatory requirements that vary from country to country and continue to change. Any of these risks and others may prevent or delay us from successfully reintroducing and commercializing OMONTYS, including the following:


•	product quality issues;


•	cost overruns, process scale-up, process reproducibility;


•	changes in demand forecasts that result in inventory write-offs;


•	difficulties in maintaining or upgrading equipment and manufacturing facilities on a timely basis; and


•	regulatory issues or changes that may cause significant modifications in the manufacturing process or facilities or otherwise impact our ability to offer competitive product presentations or formulations.

~~While~~As we ~~continue to be responsible for the manufacture of API based on Takeda's forecasts, we~~ have transferred responsibility for the manufacture of OMONTYS ~~finished product~~ to Takeda, and we therefore have limited control and ability to address risks associated with ~~that portion of~~ the manufacturing process~~. Further~~, ~~some~~including ~~of our, and Takeda's, operations, suppliers and manufacturers are currently, and planned to be,~~ single-sourced arrangements, leaving usOMONTYS at greater risk of supply interruptions, potential delays and failure to be successfully ~~commercialize~~reintroduced or commercialized.

We, Takeda, and our third-party manufacturers are required to comply with applicable FDA manufacturing practice and other applicable regulations. If there is any failure by us, Takeda or one of our third-party manufacturers or suppliers to maintain compliance with these regulations, the production of OMONTYS could be interrupted, resulting in delays and additional costs should we reintroduce OMONTYS. Due to the product recall of OMONTYS, manufacturing activities have also been significantly reduced. If for any reason these third parties are unable or unwilling to perform under our agreements or enter into new agreements with us, we may not be able to locate alternative manufacturers or enter into favorable agreements with them in an expeditious manner. This could result in further losses and reduced profits that we share from the sale of OMONTYS. Any inability to acquire sufficient quantities of OMONTYS or components thereof in a timely manner from third parties could delay clinical trials or result in product shortages and prevent us from reintroducing and commercializing OMONTYS in a cost-effective manner or on a timely basis. Further, our lack of experience providing reliable supply of product may deter health care providers and dialysis centers from selecting, or switching to, OMONTYS from our competitors' products or from continuing to use OMONTYS should it be reintroduced.19

It is difficult and costly to protect our proprietary rights, and we may not be able to ensure their protection.

Our success will depend in part on obtaining and maintaining patent protection and trade secret protection of OMONTYS and any other product candidates we may pursue, their use and the methods used to manufacture them, as well as successfully defending these patents against third-party challenges. Our ability to protect OMONTYS from unauthorized making, using, selling, offering to sell or importation by third parties is dependent upon the extent to which we have rights under valid and enforceable patents, or have trade secrets that cover these activities.

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~~Moreover,~~Takeda and our third-party ~~parties~~manufacturers ~~may~~are ~~challenge~~required ~~the~~to ~~patents,~~comply ~~patent~~with ~~applications~~applicable FDA manufacturing practice and other ~~proprietary~~applicable ~~rights~~regulations. If ~~held~~there byis ~~our~~any ~~licensors~~failure orto ~~collaborators~~maintain compliance with these regulations, the production of OMONTYS could be interrupted, resulting in delays and additional costs should reintroduction of OMONTYS be feasible. Further, WeTakeda's ~~generally~~lack doof ~~not~~experience ~~unilaterally~~providing ~~control~~reliable supply of product, particularly as to the ~~prosecution~~manufacturing of ~~patent~~API, ~~applications~~may ~~licensed~~cause ~~from~~delays ~~third~~in ~~parties.~~reintroduction ~~Accordingly~~of OMONTYS, weand ~~are~~deter ~~unable~~health tocare ~~exercise~~providers ~~the~~and ~~same~~dialysis ~~degree~~centers offrom ~~control~~selecting, ~~over~~or ~~this~~switching ~~intellectual~~to, ~~property~~OMONTYS asfrom weour ~~may~~competitors' ~~exercise~~products ~~over~~or ~~internally~~from ~~developed~~continuing ~~intellectual~~to ~~property~~use OMONTYS should it be reintroduced.

Our receipt of potential royalties and milestone payments associated with OMONTYS is based on the strength of the exclusive license to Takeda under our proprietary rights. We are dependent to a large extent on Takeda to protect our proprietary rights as we have given Takeda control in the first instance over such rights, and we may not be able to ensure their protection.

Our ability to receive potential royalties and milestones in connection with the reintroduction of OMONTYS will depend in part on obtaining and maintaining patent protection and trade secret protection of OMONTYS. Under the recent amendment to the collaboration, we have granted Takeda the first right, but not the obligation, to pursue prosecution and maintenance of these proprietary rights as well as successfully defending these patents against third-party challenges. The ability to protect OMONTYS from unauthorized making, using, selling, offering to sell or importation by third parties is dependent upon the extent to which we have rights under valid and enforceable patents, or have trade secrets that cover these activities and the extent to which Takeda pursues enforcement. We have limited resources to pursue any enforcement ourselves that Takeda chooses not to pursue.

We have licensed from third parties rights to numerous issued patents and patent applications. The rights that we acquire from licensors or collaborators are protected by patents and proprietary rights owned by them, and we rely on the patent protection and rights established or acquired by them. The remaining patent terms may not provide meaningful protection. Moreover, third parties may challenge the patents, patent applications and other proprietary rights held by our licensors or collaborators. We generally do not unilaterally control the prosecution of patent applications licensed from third parties, and any such control has generally been conferred to Takeda in connection with the amendment of our collaboration. Accordingly, we are unable to exercise the same degree of control over this intellectual property as we may exercise over internally developed intellectual property.

Even if we are able to obtain issued patents, any patent may be challenged, invalidated, held unenforceable or circumvented. The existence of a patent will not necessarily protect us from competition or from claims of a third party that our products infringe their issued patents. No consistent policy regarding the breadth of claims allowed in biotechnology patents has emerged to date in the U.S. The biotechnology patent situation outside the U.S. is even more uncertain. Competitors may successfully challenge our patents, produce similar drugs or products that do not infringe our patents, or produce drugs in countries where we have not applied for patent protection or that do not respect our patents. Accordingly, we cannot predict the breadth of claims that may be allowed or enforced in our licensed patents, in our patents or in third-party patents or applications therefor.

The degree of future protection to be afforded by our proprietary rights is uncertain because legal means afford only limited protection and may not adequately protect our rights or permit us to gain or keep our competitive advantage. For example:


•	others may be able to make similar compounds but that are not covered by the claims of our patents, or for which we are not licensed under our license agreements;


•	we or our licensors or collaborators might not have been the first to make the inventions covered by our pending patent applications or the pending patent applications and issued patents of our licensors;


•	we or our licensors or collaborators might not have been the first to file patent applications for these inventions;


•	others may independently develop similar or alternative technologies or duplicate any of our technologies without infringing our intellectual property rights;


•	it is possible that our pending patent applications will not result in issued patents;


•	our issued patents and the issued patents of our licensors or collaborators may not provide us with any competitive advantages, or may be held invalid or unenforceable as a result of legal challenges by third parties;

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•	we may not develop additional proprietary technologies that are patentable; or


•	the patents of others may have an adverse effect on our business.

We also may rely on trade secrets to protect our technology, especially where we do not believe patent protection is appropriate or obtainable. However, trade secrets are difficult to protect. Although we use reasonable efforts to protect our trade secrets, our employees, consultants, contractors, outside scientific collaborators and other advisors may unintentionally or willfully disclose our information to competitors. Enforcing a claim that a third party illegally obtained and is using any of our trade secrets is expensive and time consuming, and the outcome is unpredictable. In addition, courts outside the U.S. are sometimes less willing to protect trade secrets. Moreover, our competitors may independently develop equivalent knowledge, methods and know-how.

Our R&D collaborators may have rights to publish data and other information to which we have rights. In addition, we sometimes engage individuals or entities to conduct research that may be relevant to our business. The ability of these individuals or entities to publish or otherwise publicly disclose data and other information generated during the course of their research is subject to certain contractual limitations. These contractual provisions may be insufficient or inadequate to protect our trade secrets and may impair our patent rights. If we do not apply for patent protection prior to such publication or if we cannot otherwise maintain the confidentiality of our technology and other confidential information, then our ability to receive patent protection or protect our proprietary information may be jeopardized.

WeSubstantial costs may ~~incur~~arise ~~substantial costs~~ as a result of litigation or other proceedings relating to patent and other intellectual property rights and we may be unable to protect our rights to, or use, our technology.

~~Our~~The ability, ~~and the ability of our commercial partners,~~ to reintroduce and commercialize OMONTYS will depend, in part, on ~~our~~the ability to obtain patents, enforce those patents and operate without infringing the proprietary rights of third parties. The patent positions of biotechnology and pharmaceutical companies can be highly uncertain and involve complex legal and factual questions. We have filed multiple U.S. patent applications and foreign counterparts related to OMONTYS and other programs as well as underlying platform technologies and Takeda may file additional U.S. and foreign patent applications related thereto. There can be no assurance that any issued patents we or Takeda own or control will provide sufficient protection to conduct our business as presently conducted or as proposed to be conducted, that any patents will issue from the patent applications owned by us, or that we will remain free from infringement claims by third parties.

23The failure to obtain adequate patent protection would have a material adverse effect on us and may adversely affect our ability to enter into, or affect the terms of, any arrangement for the further development and marketing of any product. There can also be no assurance that patents owned by us will not be challenged by others. We could incur substantial costs in proceedings, including interference proceedings before the U.S. Patent and Trademark Office and comparable proceedings before similar agencies in other countries in connection with any claims that may arise in the future. These proceedings could result in adverse decisions about the patentability of our inventions and products, as well as about the enforceability, validity or scope of protection afforded by our patents. We have limited financial resources with which to maintain and enforce patent protection should Takeda choose not to take protective action.

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The patent positions of biotechnology and pharmaceutical companies can be highly uncertain and involve complex legal and factual questions. We have filed multiple U.S. patent applications and foreign counterparts related to OMONTYS and other programs as well as underlying platform technologies and may file additional U.S. and foreign patent applications related thereto. There can be no assurance that any issued patents we own or control will provide sufficient protection to conduct our business as presently conducted or as proposed to be conducted, that any patents will issue from the patent applications owned by us, or that we will remain free from infringement claims by third parties.

The failure to obtain adequate patent protection would have a material adverse effect on us and may adversely affect our ability to enter into, or affect the terms of, any arrangement for the further development and marketing of any product. There can also be no assurance that patents owned by us will not be challenged by others. We could incur substantial costs in proceedings, including interference proceedings before the U.S. Patent and Trademark Office and comparable proceedings before similar agencies in other countries in connection with any claims that may arise in the future. These proceedings could result in adverse decisions about the patentability of our inventions and products, as well as about the enforceability, validity or scope of protection afforded by our patents.

Patent applications in the U.S. and elsewhere are published only after 18 months from the priority date. The publication of discoveries in the scientific or patent literature frequently occurs substantially later than the date on which the underlying discoveries were made. Therefore, patent applications relating to products similar to OMONTYS and any future products may have already been filed by others without our knowledge. In the event an infringement claim is brought against us, we may be required to pay substantial legal and other expenses to defend such a claim and, if we are unsuccessful in defending the claim, we may be prevented from pursuing related product development and commercialization and may be subject to damage awards.

Any future patent litigation, interference or other administrative proceedings will result in additional expense and distraction of our personnel. An adverse outcome in such litigation or proceedings may expose us or our collaborators to loss of our proprietary position or to significant liabilities, or require us to seek licenses that may not be available from third parties on commercially acceptable terms or at all. In addition, we may be restricted or prevented from manufacturing or reintroducing and commercializing OMONTYS or from developing, manufacturing and selling any future products in the event of an adverse determination in a judicial or administrative proceeding or if we fail to obtain necessary licenses. If it is determined that we have infringed an issued patent, we could be compelled to pay significant damages, including punitive damages.

Virtually all of our competitors are able to sustain the costs of complex patent litigation more effectively than we can because they have substantially greater resources. In addition, any uncertainties resulting from the initiation and continuation of any litigation could have a material adverse effect on our ability to raise the funds necessary to continue our operations, in-license technology that we need, out-license our existing technologies or enter into collaborations that would assist in commercially exploiting any technology.

We may be unable to continue our operations, meet our obligations, and reintroduce and commercialize OMONTYS as a result of our recent reorganization plan, further reductions in force or any loss of services of senior management and key personnel.21

We are highly dependent upon our senior management and key personnel, however, due to the significant challenges to our business, our recent reorganization and further reductions in force, or the loss of any of their services, for any reason, could negatively impact our operations. We will need to maintain personnel as we investigate the cause of the safety concerns related to OMONTYS, search for and implement a solution to address it, potentially reintroduce and further commercialize OMONTYS and conduct post-marketing studies and trials. Competition for qualified personnel in the biotechnology and pharmaceuticals field is intense. We may not be able to maintain personnel on acceptable terms. In addition, each of our officers and key personnel may terminate his/her employment at any time without notice and without cause or good reason.

Risks Related to Our Industry

Even though OMONTYS approval by the FDA has not been permanently withdrawn, the OMONTYS approval is subject to continued FDA inspection of the safety concerns leading to the recall. Ongoing FDA review may result in significant additional expense and limit our ability to reintroduce and successfully commercialize OMONTYS.

Although the FDA approval of OMONTYS has not been withdrawn, the FDA may choose to do so as the investigation continues or to subject us to various post-marketing requirements, including additional clinical trials, and the labeling, packaging, adverse event reporting, storage, advertising, promotion and recordkeeping for the product will be subject to extensive and ongoing regulatory requirements. The recent cases of reported patients' serious hypersensitivity reactions to

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~~OMONTYS~~of ~~and~~ any ~~other~~litigation ~~subsequent~~could ~~discovery~~have ofa ~~previously~~material ~~unknown problems with the product, including~~ adverse ~~events~~effect ~~of unanticipated severity or frequency, may result in withdrawal or restrictions~~ on ~~the~~our ~~marketing~~ability ofto ~~the~~raise ~~product, and could include regulatory actions from~~ the ~~FDA. The~~funds ~~actions~~necessary ~~the~~to ~~FDA~~continue ~~may~~our ~~take include~~operations, ~~permanent~~in-license ~~withdrawal,~~technology ~~additional~~that ~~studies~~we ~~or label restrictions~~need, ~~the~~out-license ~~use~~our ofexisting ~~informed~~technologies ~~consents, the addition of more restrictive REMs, further lowering of target hemoglobin levels,~~ or ~~even~~enter ~~the~~into ~~removal~~collaborations ~~of indications from the label altogether. In addition, the FDA's policies may change and additional government regulations may be enacted~~ that ~~could~~would ~~prevent~~assist or delay successful reintroduction and commercialization of OMONTYS. We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action, either in ~~the~~commercially ~~U.S.~~exploiting ~~or abroad. If we are not able to maintain regulatory compliance, we might not be permitted to market OMONTYS, or~~ any ~~future product, and we may not achieve or sustain profitability~~technology.

Risks Related to Our Industry

Even though OMONTYS' approval by the FDA has not been permanently withdrawn, the OMONTYS approval is subject to continued FDA inspection of the safety concerns leading to the recall. Ongoing FDA review may result in significant additional expense and limit Takeda's ability to reintroduce and successfully commercialize OMONTYS.

Although the FDA approval of OMONTYS has not been withdrawn, the FDA may choose to do so as the investigation continues or to subject Takeda to various post-marketing requirements, including additional clinical trials, and the labeling, packaging, adverse event reporting, storage, advertising, promotion and recordkeeping for the product will be subject to extensive and ongoing regulatory requirements. The recent cases of reported patients' serious hypersensitivity reactions to OMONTYS and any other subsequent discovery of previously unknown problems with the product, including adverse events of unanticipated severity or frequency, may result in withdrawal or restrictions on the marketing of the product, and could include regulatory actions from the FDA. The actions the FDA may take include, permanent withdrawal, additional studies or label restrictions, the use of informed consents, the addition of more restrictive REMs, further lowering of target hemoglobin levels, or even the removal of indications from the label altogether. In addition, the FDA's policies may change and additional government regulations may be enacted that could prevent or delay successful reintroduction and commercialization of OMONTYS. We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action, either in the U.S. or abroad. If Takeda is not able to maintain regulatory compliance or the FDA imposes additional requirements, then Takeda may not be able to reintroduce and successfully commercialize OMONTYS, which would prevent us from obtaining potential royalties or milestones from the product.

If we fail to comply with federal and state healthcare laws, including fraud and abuse and healthcare privacy and security laws, we could face substantial penalties that could adversely affect our business, financial condition and results of operations.

We are subject to federal and state healthcare laws, including fraud and abuse and healthcare privacy and security laws. The healthcare laws that may affect our ability to operate include:

•

federal “sunshine” laws that require transparency regarding financial arrangements with healthcare providers, such as the reporting and disclosure requirements imposed on drug manufacturers by the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Affordability Reconciliation Act, or collectively, PPACA, regarding any “transfer of value” made or distributed to prescribers and other health care providers;

•

the federal healthcare programs' Anti-Kickback Law, which prohibits, among other things, persons from knowingly and willfully soliciting, receiving, offering or paying remuneration, directly or indirectly, in exchange for or to induce either the referral of an individual for, or the purchase, order or recommendation of, any good or service for which payment may be made under federal healthcare programs such as the Medicare and Medicaid programs;

•

federal false claims laws which prohibit, among other things, individuals or entities from knowingly presenting, or causing to be presented, claims for payment from Medicare, Medicaid, or other third-party payors that are false or fraudulent; the federal Health Insurance Portability and Accountability Act of 1996, or HIPAA, which created federal criminal laws that prohibit executing a scheme to defraud any health care benefit program or making false statements relating to health care matters;


•	the Federal Food, Drug and Cosmetic Act, which prohibits, among other things, individuals or entities from introducing into interstate commerce any food, drug, device or cosmetic that has been adulterated or misbranded; and


•	state law equivalents of certain of the above federal laws, such as anti-kickback and false claims laws which may apply to items or services reimbursed by any third-party payor, including commercial insurers.

In addition, California, and other states such as Massachusetts and Vermont, mandate implementation of comprehensive compliance programs to ensure compliance with these laws.

Many of these laws have not been fully interpreted by applicable regulatory authorities or the courts and their provisions are subject to a variety of interpretations, which increases the risk that we may be found in violation of these laws. Violations of these laws are punishable by criminal and civil sanctions, including, in some instances, exclusion from participation in federal and state healthcare programs, including Medicare and Medicaid, and the curtailment or restructuring of operations. The recall has severely harmed our business and financial condition and prospects as a going concern and we may not be able to continue the business and operations of the Company. Accordingly, we may face challenges to maintain operations and a compliance program that are in material compliance with these laws. Because of the far-reaching nature of these laws and the significant disruption to our operations resulting from the recall, there can be no assurance that we would not be required to alter one or more of our practices to be in compliance, or that the occurrence of one or more violations would not result in a material adverse effect on our financial condition and results of operations.22

Failure to obtain regulatory approval in foreign jurisdictions will prevent us from marketing our products abroad and obtaining certain regulatory milestones through our Takeda collaboration.

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WeMany ~~co-marketed OMONTYS in the U.S. before our recent recall~~ of ~~OMONTYS,~~these ~~and~~laws have ~~exclusively~~not ~~licensed~~been ~~Takeda~~fully tointerpreted ~~market~~by ~~the~~applicable ~~product~~regulatory inauthorities ~~foreign~~or ~~jurisdictions.~~the ~~When~~courts and iftheir weprovisions ~~reintroduce~~are ~~OMONTYS,~~subject into ~~order~~a tovariety ~~market~~of ~~the~~interpretations, ~~product~~which inincreases the ~~E.U.~~risk ~~and~~that ~~other~~we ~~foreign~~may ~~jurisdictions,~~be ~~Takeda~~found orin aviolation ~~sublicensee~~of ~~must~~these ~~obtain separate regulatory approvals~~laws. WeViolations ~~have~~of ~~had~~these ~~limited~~laws ~~interactions~~are ~~with~~punishable ~~foreign~~by ~~regulatory~~criminal ~~authorities,~~ and ~~the~~civil ~~approval~~sanctions, ~~procedures~~including, ~~vary~~in ~~among~~some ~~countries~~instances, ~~and~~exclusion ~~can~~from ~~involve~~participation ~~additional~~in ~~testing,~~federal and ~~the~~state ~~time~~healthcare ~~required~~programs, toincluding ~~obtain~~Medicare ~~approval~~and ~~may~~Medicaid, ~~differ~~and ~~from~~the ~~that~~curtailment ~~required~~or torestructuring ~~obtain~~of ~~FDA approval~~operations. ~~Approval~~The byrecall ~~the~~has ~~FDA~~severely ~~does~~harmed ~~not~~our ~~ensure~~business ~~approval~~and byfinancial ~~regulatory~~condition ~~authorities~~and inprospects ~~other~~as ~~countries,~~a ~~and~~going ~~approval~~concern byand ~~one~~we ~~foreign~~may ~~regulatory~~not ~~authority~~be ~~does~~able ~~not~~to ~~ensure~~continue ~~approval~~the bybusiness ~~regulatory~~and ~~authorities~~operations inof ~~other~~the ~~foreign countries~~Company. ~~The~~ Accordingly, ~~foreign~~we ~~regulatory approval process~~ may ~~include~~face ~~all~~challenges ofto ~~the~~maintain ~~risks~~operations ~~associated~~and ~~with~~a ~~obtaining~~compliance ~~FDA~~program ~~approval. In~~that ~~addition, there~~ are ain ~~number~~material ofcompliance ~~ESAs~~with ~~available~~these inlaws. Because of the ~~E.U.~~far-reaching ~~and~~nature ~~other~~of ~~foreign~~these ~~markets,~~laws and ~~therefore~~the itsignificant ~~may~~disruption ~~be more challenging~~ to ~~obtain~~our ~~regulatory~~operations ~~approval~~resulting infrom ~~such markets because~~ the ~~risk/benefit~~recall, ~~analysis~~there ~~for~~can ~~approval may~~ be ~~different~~no ~~than~~assurance inthat ~~the~~we ~~U.S. Foreign~~would ~~regulatory approvals may~~ not be ~~obtained~~required onto aalter ~~timely~~one ~~basis, if at all. If we~~ or ~~Takeda,~~more ~~as part~~ of our ~~collaboration,~~practices ~~are not able~~ to ~~obtain~~be ~~regulatory approval~~ in ~~any~~compliance, ~~foreign~~or ~~market,~~that ~~then~~the weoccurrence ~~will~~of ~~not~~one beor ~~able~~more toviolations ~~commercialize~~would ~~OMONTYS~~not result in ~~any~~a ~~foreign~~material ~~market,~~adverse ~~and~~effect weon ~~will~~our ~~not~~financial ~~obtain~~condition ~~certain~~and ~~regulatory~~results ~~milestones~~of ~~from Takeda~~operations.

~~Foreign~~Failure ~~governments~~to ~~often~~obtain ~~impose~~regulatory ~~strict~~approval ~~price~~in ~~controls~~foreign jurisdictions will prevent Takeda from marketing OMONTYS abroad, which ~~may~~will ~~adversely~~prevent ~~affect~~us from obtaining potential royalties and milestones through our ~~future~~amended ~~profitability~~collaboration with Takeda .

~~When~~We and ifTakeda weco-marketed ~~reintroduce~~ OMONTYS in the U.S. before the product recall, and through our amended collaboration agreement with Takeda we ~~intend~~are entitled to ~~seek~~potential ~~approval~~royalties and milestones related to ~~market~~marketing the product, ~~through~~in ~~our~~foreign jurisdictions. When and if Takeda ~~collaboration~~reintroduces OMONTYS, in ~~foreign~~order ~~jurisdictions. If~~to wemarket ~~obtain~~the ~~approval~~product in ~~one~~the orE.U. ~~more~~and other foreign jurisdictions, weTakeda ~~will~~or bea ~~subject~~sublicensee tomust ~~rules and~~obtain ~~regulations~~separate inregulatory ~~those~~approvals. The ~~jurisdictions~~regulatory ~~relating~~approval toprocedures ~~our~~vary ~~product. In~~among ~~some~~countries ~~foreign~~and ~~countries,~~can ~~particularly~~involve inadditional testing, and the ~~E.U.,~~time ~~prescription~~required ~~drug~~to ~~pricing~~obtain isapproval ~~subject~~may differ from that required to ~~governmental~~obtain ~~control~~FDA approval. InApproval ~~these~~by the FDA does not ensure approval by regulatory authorities in other countries, ~~pricing~~and ~~negotiations~~approval ~~with~~by ~~governmental~~one foreign regulatory authority does not ensure approval by regulatory authorities ~~can~~in ~~take~~other ~~considerable~~foreign ~~time~~countries. The ~~after~~foreign ~~the~~regulatory ~~receipt~~approval process may include all of ~~marketing~~the ~~approval~~risks ~~for~~associated awith ~~drug~~obtaining ~~candidate~~FDA approval. ToIn ~~obtain~~addition, ~~reimbursement~~there orare ~~pricing~~a ~~approval~~number of ESAs available in ~~some~~the ~~countries~~E.U. and other foreign markets, weand therefore it may be ~~required~~more challenging to ~~conduct~~obtain aregulatory ~~clinical~~approval ~~trial~~in ~~that~~such ~~compares~~markets because the ~~cost-effectiveness~~risk/benefit ofanalysis for approval may be different than in the ~~product~~U.S. Foreign toregulatory ~~other~~approvals ~~available~~may ~~therapies~~not orbe aobtained ~~clinical~~on ~~trial~~a ~~that~~timely ~~studies~~basis, ~~pharmacoeconomic~~if ~~benefits~~at all. If ~~reimbursement~~Takeda ofis ~~the~~not ~~product~~able isto ~~unavailable~~obtain orregulatory ~~limited~~approval in ~~scope~~any orforeign ~~amount~~market, orthen ifTakeda ~~pricing~~will isnot ~~set~~be atable ~~unsatisfactory~~to ~~levels~~commercialize OMONTYS in any foreign market, and we ~~may~~will benot ~~unable~~obtain tocertain ~~achieve~~regulatory milestones or ~~sustain~~royalties ~~profitability~~from Takeda.

Foreign governments often impose strict price controls, which may adversely affect the future profitability of OMONTYS.

When and if Takeda reintroduces OMONTYS in the U.S., Takeda intends to seek approval to market the product in foreign jurisdictions. If Takeda obtains approval in one or more foreign jurisdictions, Takeda will be subject to rules and regulations in those jurisdictions relating to OMONTYS. In some foreign countries, particularly in the E.U., prescription drug pricing is subject to governmental control. In these countries, pricing negotiations with governmental authorities can take considerable time after the receipt of marketing approval for a drug candidate. To obtain reimbursement or pricing approval in some countries, Takeda may be required to conduct a clinical trial that compares the cost-effectiveness of OMONTYS to other available therapies or a clinical trial that studies pharmacoeconomic benefits. If reimbursement of the product is unavailable or limited in scope or amount, or if pricing is set at unsatisfactory levels, Takeda may be unable to achieve or sustain profitability of the product, which would adversely affect our ability to obtain potential royalties or milestones for the product.

We may incur significant costs complying with environmental laws and regulations, and failure to comply with these laws and regulations could expose us to significant liabilities.

We ~~use~~have used hazardous chemicals and radioactive and biological materials in our business and are subject to a variety of federal, state and local laws and regulations governing the use, generation, manufacture, storage, handling and disposal of these materials. Although we believe our safety procedures for handling and disposing of these materials and waste products comply with these laws and regulations, we cannot eliminate the risk of accidental injury or contamination from the use, storage, handling or disposal of hazardous materials. In the event of contamination or injury, we could be held liable for any resulting damages. We are uninsured for third-party contamination injury.

Risks Related to the Ownership of Our Common Stock

We have been named as a defendant in ~~a purported~~ securities class action ~~lawsuit.~~lawsuits ~~This~~and ~~lawsuit~~related derivative lawsuits. These lawsuits could result in substantial damages ~~and may divert management's time and attention from our business and operations~~.

On February 27, 2013, a purported securities class action complaint was filed in the U.S. District Court for the Northern District of California, naming as defendants us, certain of our officers, Takeda, Takeda Pharmaceuticals U.S.A., Inc. and Takeda Global Research & Development Center, Inc. The complaint, filed on behalf of a putative class of persons who purchased our common stock between December 8, 2011 and February 22, 2013, or the Class Period, alleges violations of Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder, in connection with allegedly false and misleading statements made by the defendants regarding our company's business practices, financial projections and other disclosures during the Class Period. The complaint seeks damages, costs and expenses and such other relief as determined by the Court, and the complainant seeks to represent a class comprised of purchasers of our common stock during the Class Period. A response to the complaint is not yet due.23

Our management believes that we have meritorious defenses and intends to defend this lawsuit vigorously. However, this lawsuit is subject to inherent uncertainties, and the actual cost will depend upon many unknown factors. The outcome of the litigation is necessarily uncertain, we could be forced to expend significant resources in the defense of the suit and we may not prevail. Monitoring and defending against legal actions is time consuming for our management and detracts from our ability to fully focus our internal resources on our business activities. In addition, we may incur substantial legal fees and costs in connection with the litigation and, although we believe our company is entitled to coverage under the relevant insurance policies, subject to a retention, coverage could be denied or prove to be insufficient. We are not currently able to estimate the possible cost to us from this matter, as this lawsuit is currently at an early stage and we cannot be certain how long it may take

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toOn ~~resolve~~February ~~this~~27, ~~matter~~2013, ora securities class action complaint was filed in the ~~possible~~United ~~amount~~States District Court for the Northern District of ~~any~~California, ~~damages~~naming ~~that~~as wedefendants ~~may~~the beCompany, ~~required~~certain toof ~~pay~~its officers, Takeda Pharmaceutical Company Limited, Takeda Pharmaceuticals U. WeS.A., ~~have~~Inc. ~~not~~and ~~established~~Takeda ~~any~~Global ~~reserves~~Research ~~for~~& ~~any~~Development ~~potential~~Center, ~~liability~~Inc. A ~~relating~~second tocomplaint ~~this~~naming ~~lawsuit~~the same defendants was filed on March 6, 2013. It isOn ~~possible~~May 2, 2013, the securities class action complaint that wewas ~~could~~filed on February 27, 2013 was voluntarily dismissed by the plaintiff. On May 21, 2013, the Court appointed a lead plaintiff in the ~~future~~remaining securities class action complaint that had been filed on March 6, ~~incur~~2013. On ~~judgments~~July or22, ~~enter~~2013, ~~into~~a ~~settlements~~consolidated amended class action complaint was filed on behalf of ~~claims~~purported ~~for~~stockholders ~~monetary~~of ~~damages~~the Company, naming as defendants the Company and certain of its former officers. A The ~~decision~~consolidated ~~adverse~~amended tocomplaint ~~our~~alleges ~~interests~~violations onof ~~these~~Section ~~actions~~10(b) ~~could~~and ~~result~~20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder, in connection with allegedly false and misleading statements made by the ~~payment~~defendants regarding OMONTYS, the Company's business practices, financial projections and other disclosures between August 8, 2012 and February 22, 2013, or the Class Period. The plaintiff seeks to represent a class comprised of ~~substantial~~purchasers of the Company's common stock during the Class Period and seeks damages, orcosts ~~possibly~~and ~~fines~~expenses and such other relief as determined by the Court. On September 20, 2013, the Company and ~~could~~the ~~have~~individual defendants (collectively, “Defendants”) filed a ~~material~~motion ~~adverse~~to ~~effect~~dismiss the consolidated amended complaint. On November 19, 2013, the plaintiff filed her opposition to the motion to dismiss and on ~~our~~December ~~cash~~19, ~~flow~~2013, ~~results~~Defendants filed their reply in support of ~~operations~~their ~~and~~motion ~~financial~~to ~~position~~dismiss. In The ~~addition~~hearing on the motion to dismiss occurred on January 15, 2014. On January 21, 2014, the ~~uncertainty~~Court ofissued its order granting the ~~currently~~motion ~~pending~~to ~~litigation~~dismiss ~~could~~regarding ~~lead~~violations of Section 20(a) against all Defendants and it granted the motion to ~~more~~dismiss ~~volatility~~in part, denying the motion to dismiss in ~~our~~part, ~~stock~~and ~~price~~providing plaintiffs with an opportunity to amend the complaint. On February 18, 2014, the Court, pursuant to a stipulation by the parties, stayed the litigation for ninety days to allow the parties to conduct settlement discussions.

On March 19, 2013 and March 29, 2013, respectively, two derivative lawsuits were filed purportedly on behalf of the Company in California Superior Court for the County of Santa Clara naming certain of our current and former officers and directors as defendants (the “State Court Derivative Action”). The lawsuits allege that certain of the Company's officers and directors breached their fiduciary duties related to the clinical trials for OMONTYS and for representations regarding the Company's business health, which was tied to the success of OMONTYS. The lawsuits also assert claims for unjust enrichment and corporate waste. On May 31, 2013, the Court consolidated the two actions and appointed lead plaintiff. On June 11, 2013, lead plaintiff designated the complaint filed on March 29, 2013 as the operative complaint. On August 6, 2013, the Court stayed the State Court Derivative Action pending the outcome of the motion to dismiss in the securities class action. Subsequent to the order regarding the motion to dismiss in the securities class action, on January 31, 2014, the Court ordered that the State Court Derivative Action be stayed in its entirety until resolution of the securities class action.

On August 19, 2013, another derivative lawsuit was filed purportedly on behalf of the Company in the United States District Court for the Northern District of California naming certain of our current and former officers and directors as defendants (the “Federal Derivative Action”). The lawsuit’s allegations are substantially similar to the allegations in the State Court Derivative Action. On October 21, 2013, the Court ordered a stay in the Federal Derivative Action pending the outcome of the motion to dismiss in the securities class action. Subsequent to the order regarding the motion to dismiss in the securities class action, on January 31, 2014, the Court ordered that the Federal Derivative Action be stayed until resolution of the securities class action.

Additional complaints may be filed against us and our directors and officers related to our recall of OMONTYS.

Our management believes that we have meritorious defenses and intends to defend these lawsuits vigorously. However, these lawsuits are subject to inherent uncertainties, the actual cost may be significant, and we may not prevail. We believe we are entitled to coverage under our relevant insurance policies, subject to a retention, but coverage could be denied or prove to be insufficient. In addition, it is possible total liability could exceed our insurance limits.

We have been delisted from The NASDAQ Stock Market and our shares currently trade Over The Counter. We remain subject to additional expenses and administrative burden as a public company.

On May 28, 2013, we received a determination letter from the Nasdaq Stock Market indicating that Nasdaq believes that our stock should be delisted pursuant to Rule 5101 of the Nasdaq Listing Rules. Specifically, Nasdaq notified us that in their opinion we are operating as a “public shell” and has determined that, following the Company’s announcement regarding the voluntary recall of OMONTYS, we no longer have an operating business.

Nasdaq has determined that public shells could be detrimental to the interests of the investing public. Nasdaq Listing Rule 5100 provides Nasdaq with discretionary authority to apply more stringent criteria for continued listing and the ability to terminate the inclusion of particular securities based on any event, condition or circumstance that exists or occurs that in the opinion of Nasdaq makes inclusion of the securities on Nasdaq inadvisable or unwarranted.

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We did not appeal this determination and as a result, on the opening of business June 6, 2013, we were suspended from the Nasdaq Stock Market and began trading on the Over The Counter electronic market (OTCQB). On July 19, we received notice from the Nasdaq Stock Market that Nasdaq filed a Form 25 with the Securities and Exchange Commission to complete delisting.

The risk resulting from Nasdaq delisting and the potential for additional securities litigation may be particularly relevant for us because we have experienced greater than average stock price volatility, as have other biotechnology companies in recent years. OTC markets are generally considered less liquid which may lead to greater stock price volatility. We are currently subject to securities class action and other litigation and we may be subject to additional lawsuits or proceedings in the future. The securities class action litigation could result in substantial costs and divert management's attention and resources, which could harm our business, operating results and financial condition.

In addition, as a public company, we continue to incur significant legal, accounting and other expenses and our administrative staff is required to perform additional tasks, such as adopting additional internal controls, disclosure controls and procedures, retaining a transfer agent and bearing all of the internal and external costs of preparing and distributing periodic public reports in compliance with our obligations under the securities laws.

The market price of our common stock has been highly volatile and is likely to remain highly volatile, and you may not be able to resell your shares at or above your purchase price.

The trading price of our common stock has been highly volatile. For the 52 weeks ended December 31, ~~2012~~2013, the closing price of our common stock ranged between a high of $2721.4656 per share and a low of $60.5076 per share. The closing price for our common stock as reported by ~~the~~The ~~NASDAQ~~OTCMKTS ~~Global~~Stock ~~Select~~ Market on ~~February 28~~March 12, ~~2013~~2014 was $20.6589 per share.

Our stock is expected to be subject to wide fluctuations in price in response to various factors, many of which are beyond our control, including:

• ~~our~~Takeda's ability to rapidly identify and address the cause of the safety concerns related to OMONTYS;

• ~~our~~Takeda's ability to demonstrate safety of OMONTYS to the satisfaction of the FDA and reintroduce ~~such~~the product;


•	our ability to fund our operations and continue as a going concern;

• litigation, including the ~~purported~~ securities class action ~~lawsuit~~lawsuits and derivative lawsuits pending against us and certain of our officers;


•	changes in the market valuations of similar companies;

• actual or anticipated results from, and any delays in, commercialization of OMONTYS should weTakeda reintroduce ~~OMONTYS~~the product;

• actual or anticipated contractual arrangements for OMONTYS should weTakeda reintroduce OMONTYS or competing products;


•	actual or anticipated changes in our funding requirements, capital resources and our ability to obtain financing and the terms thereof;


•	actual or anticipated actions taken by regulatory agencies including the FDA and CMS with respect to ESAs generally or OMONTYS specifically;

• new products or services introduced or announced by usTakeda or our ~~collaboration partners, or our~~ competitors, including Roche's Mircera or biosimilars, and the timing of these introductions or announcements;

• actions taken by regulatory agencies with respect to clinical trials, manufacturing process or sales and marketing activities for OMONTYS;

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•	changes in laws or regulations applicable to OMONTYS;

• ~~the~~developments ~~success~~concerning of our ~~efforts~~amended tocollaboration ~~discover,~~arrangement ~~acquire~~with ~~or in-license additional products or product candidates~~Takeda;

• ~~developments~~actual ~~concerning~~or ~~our~~anticipated ~~collaborations,~~variations ~~including~~in ~~but not limited to those with~~ our ~~sources~~quarterly ofoperating ~~manufacturing~~results ~~supply~~due ~~and~~to our ~~commercialization~~restructuring ~~partners~~efforts;

• actual or anticipated variations in our quarterly operating results;

• announcements of technological innovations by us, our collaborators or our competitors;

• actual or anticipated changes in earnings estimates or recommendations by securities analysts;


•	conditions or trends in the biotechnology and biopharmaceutical industries;

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•	announcements by us or our competitors of significant acquisitions, strategic partnerships, joint ventures or capital commitments;


•	general economic and market conditions and other factors that may be unrelated to our operating performance or the operating performance of our competitors;


•	sales of common stock or other securities by us or our stockholders in the future;

• ~~additions~~the orloss ~~departures~~of services of ~~key~~substantially ~~management~~all orof ~~other~~our personnel, including all of our executive officers;


•	developments relating to proprietary rights held by us or our competitors;


•	disputes or other developments relating to proprietary rights, including patents, litigation matters and our ability to obtain patent protection for our technologies; and


•	trading volume of our common stock.

In addition, the stock market in general and the market for biotechnology and biopharmaceutical companies in particular have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of those companies. These broad market and industry factors may seriously harm the market price of our common stock, regardless of our operating performance.

Raising funds through our current credit arrangement may restrict our operations or place further restrictions on our operations.

In March 2012, we entered into a $30.0 million Loan Agreement with Oxford Finance LLC and Silicon Valley Bank. We initially drew $10.0 million under this agreement and are subject to a variety of affirmative and negative covenants, including required financial reporting, limitations on certain dispositions of assets, limitations on the incurrence of additional debt and other requirements. To secure our performance of our obligations under this loan and security agreement, we granted a security interest in substantially all of our assets, other than intellectual property assets, to the lenders. Our failure to comply with the terms of the loan and security agreement, the occurrence of a material impairment in our prospect of repayment or in the perfection or priority of the lender's lien on our assets, as determined by the lenders, or the occurrence of certain other specified events could result in an event of default that, if not cured or waived, could result in the acceleration of all or a substantial portion of our debt, potential foreclosure on our assets, and other adverse results. Further, we may be in breach as the voluntary recall may be considered a material adverse event under the Loan Agreement.

Failure to maintain effective internal controls in accordance with Section 404 of the Sarbanes-Oxley Act of 2002 could have a material adverse effect on our stock price.

The Sarbanes-Oxley Act of 2002 requires, among other things, that we maintain effective internal control over financial reporting and disclosure controls and procedures. We have not identified any material weaknesses in our internal controls during the years ended December 31, ~~2012~~2013, ~~2011~~2012 or ~~2010~~2011. We ~~did~~Because ~~identify~~we aare ~~material~~not ~~weakness~~an inaccelerated ~~the~~filer, ~~operation~~as defined by rule 12b-2 of the exchange act, Ernst and Young LLP was not required to issue an opinion on our internal control over financial reporting ~~that~~pursuant ~~occurred~~to ~~during~~Section ~~the~~404 ~~second quarter~~ of ~~2008~~the ~~which~~Sarbanes ~~has~~Oxley ~~been~~Act ~~fully~~of ~~remediated~~2002. We cannot assure you that material weaknesses in our internal controls will not be identified in future periods. We may have particular difficulty maintaining segregation of responsibilities with only four employees plus the services of the The Brenner Group, Inc. There can be no assurance that we will successfully and timely report on the effectiveness of our internal control over financial reporting in future periods. If we do experience a material weakness in internal controls in future periods, then investor confidence, our stock price and our ability to obtain additional financing on favorable terms could be adversely affected.

A control system, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. Because of inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues, if any, within an organization have been detected. WeThe ~~continue~~recall toof ~~implement,~~OMONTYS ~~improve~~ and ~~refine~~ our ~~disclosure~~workforce ~~controls~~reductions ~~and~~have ~~procedures and our internal control over financial reporting. The recall of OMONTYS has~~ severely harmed our business and financial condition so we may have challenges in maintaining our disclosure controls and procedures and our internal control over financial reporting.

Future sales of our common stock in the public market could cause our stock price to fall.

28Sales of a substantial number of shares of our common stock in the public market that were previously restricted from sale, or the perception that these sales might occur, could depress the market price of our common stock and could impair our ability to raise capital through the sale of additional equity securities. In the event that we do raise capital through the sale of additional equity securities, the dilution represented by the additional shares of our equity securities in the public market could

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Sales of a substantial number of shares of our common stock in the public market that were previously restricted from sale, or the perception that these sales might occur, could depress the market price of our common stock and could impair our ability to raise capital through the sale of additional equity securities. In the event that we do raise capital through the sale of additional equity securities, the dilution represented by the additional shares of our equity securities in the public market could cause our stock price to fall, in which case investors may not be able to sell their shares of our equity securities at a price equal to or above the price they paid to acquire them.

Our ability to use net operating loss carryforwards and tax credit carryforwards to offset future taxable income ~~or future tax~~ will be limited and may be further limited in the future due to ownership changes that have occurred or may occur in the future.

In general, under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, a corporation that undergoes an “ownership change” is subject to limitations on its ability to utilize its pre-change net operating losses, or NOLs, and certain other tax assets to offset future taxable income. In general, an ownership change occurs if the aggregate stock ownership of certain stockholders increases by more than 50 percentage points over such stockholders' lowest percentage ownership during the testing period (generally three years). An ownership change could limit our ability to utilize our NOL and tax credit carryforwards for taxable years including or following such “ownership change”. Prior to ~~2012~~2013, we experienced ownership changes as defined by Sections 382 and 383 of the Internal Revenue Code. Due to our announcement of our voluntary recall of OMONTYS in February 2013, there has been an extremely high volume of trading of our stock, which has caused a significant drop in the value of our stock. As a result of the high trading volume, there may be a shift of ownership amongst our 5% stockholders that could result in an ownership change, under Section 382 of the Internal Revenue Code of 1986, as amended. Limitations imposed on the ability to use NOLs and tax credits to offset future taxable income could require us to pay U.S. federal income taxes earlier than would otherwise be required if such limitations were not in effect and could cause such NOLs and tax credits to expire unused, in each case reducing or eliminating the benefit of such NOLs and tax credits. Similar rules and limitations may apply for state income tax purposes.

Some provisions of our charter documents and Delaware law may have anti-takeover effects that could discourage an acquisition of us by others, even if an acquisition would be beneficial to our stockholders.

Provisions in our certificate of incorporation and bylaws, as well as provisions of Delaware law, could make it more difficult for a third party to acquire us, even if doing so would benefit our stockholders.

These provisions include:


•	authorizing the issuance of “blank check” preferred stock, the terms of which may be established and shares of which may be issued without stockholder approval;


•	limiting the removal of directors by the stockholders;


•	prohibiting stockholder action by written consent, thereby requiring all stockholder actions to be taken at a meeting of our stockholders;


•	eliminating the ability of stockholders to call a special meeting of stockholders;


•	establishing advance notice requirements for nominations for election to the board of directors or for proposing matters that can be acted upon at stockholder meetings; and


•	our board of directors is classified, consisting of three classes of directors with staggered three-year terms, with each class consisting as nearly as possible of one third of the total number of directors.

In addition, we are subject to Section 203 of the Delaware General Corporation Law, which generally prohibits a Delaware corporation from engaging in any of a broad range of business combinations with an interested stockholder for a period of three years following the date on which the stockholder became an interested stockholder. This provision could have the effect of delaying or preventing a change of control, whether or not it is desired by or beneficial to our stockholders.

Item 1B. Unresolved Staff Comments.

Not applicable.

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Item 2. Properties.

We ~~currently~~In ~~lease~~June ~~approximately~~2013 ~~113,000~~we ~~square~~moved ~~feet~~our ofremaining ~~laboratory~~four employees into our offices in Cupertino, California and ~~office~~vacated ~~space~~all of our facilities in Palo Alto, California. We ~~under~~recorded ~~lease~~an ~~agreements~~expense ~~that~~of ~~terminate~~$2.5 inmillion ~~September~~related ~~2014~~to the termination of use of our previous office buildings. ~~Approximately~~ ~~8,000~~In ~~square~~August ~~feet~~2013 we signed an agreement with our landlord for the termination of ~~this~~the lease on our previous office ~~space~~buildings. The ~~has~~termination ~~been~~payment ~~subleased~~included toforfeiture aof ~~third~~our ~~party~~deposit ~~under~~of $50,000, release of a ~~sublease~~letter ~~agreement~~of ~~that~~credit ~~terminates~~for in$1.1 ~~August~~million ~~2014~~and cash payment of $1.4 million. InCash ~~March~~collateral ~~2013,~~for wethe ~~undertook~~letter ~~plans~~of tocredit ~~reorganize~~was held by our ~~operations~~bank inand ~~order~~shown toas ~~reduce~~restricted ~~operating~~cash ~~costs~~on our balance sheet as of December 31, ~~which~~2012. This ~~could~~cash ~~include~~was ~~consolidation~~used ~~and~~to ~~further~~fund ~~reduction~~release of ~~office~~the ~~space~~letter of credit. There is no cash held as collateral or restricted cash as of December 31, 2013.

We currently lease approximately 1,500 square feet of office space in Cupertino, California under a lease agreement that terminates in July 2014.

Item 3. Legal Proceedings

OnShareholder February 27, 2013, a securities class action complaint was filed in the United States District Court for the Northern District of California, naming as defendants Affymax, Inc. or the Company, certain of its officers, Takeda Pharmaceutical Company Limited, Takeda Pharmaceuticals U.S.A., Inc. and Takeda Global Research & Development Center, Inc. A second complaint naming the same defendants was filed on March 6, 2013. The complaints, filed on behalf of purported stockholders of the Company, allege violations of Section 10(b) and 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder, in connection with allegedly false and misleading statements made by the defendants regarding the Company's business practices, financial projections and other disclosures between December 8, 2011 and February 22, 2013, or the Class Period. The plaintiff seeks to represent a class comprised of purchasers of the Company's common stock during the Class Period and seeks damages, costs and expenses and such other relief as determined by the Court. Litigation

On ~~March~~February 1927, 2013, a ~~derivative~~securities ~~lawsuit~~class action complaint was filed ~~purportedly~~in onthe ~~behalf~~United States District Court for the Northern District of California, naming as defendants the Company, incertain ~~California~~of ~~Superior~~its officers, Takeda Pharmaceutical Company Limited, Takeda Pharmaceuticals U.S.A., Inc. and Takeda Global Research & Development Center, Inc. A second complaint naming the same defendants was filed on March 6, 2013. On May 2, 2013, the securities class action complaint that was filed on February 27, 2013 was voluntarily dismissed by the plaintiff. On May 21, 2013, the Court ~~for~~appointed a lead plaintiff in the ~~County~~remaining securities class action complaint that had been filed on March 6, 2013. On July 22, 2013, a consolidated amended class action complaint was filed on behalf of ~~Santa~~purported ~~Clara~~stockholders of the Company, naming as defendants the Company and certain of ~~our~~its former officers. The consolidated amended complaint alleges violations of Section 10(b) and ~~directors~~20(a) asof the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder, in connection with allegedly false and misleading statements made by the defendants regarding OMONTYS, the Company's business practices, financial projections and other disclosures between August 8, 2012 and February 22, 2013, or the Class Period. The ~~lawsuit~~plaintiff ~~alleges~~seeks ~~that~~to ~~certain~~represent a class comprised of purchasers of the Company's ~~officers~~common stock during the Class Period and ~~directors~~seeks ~~breached~~damages, ~~their~~costs ~~fiduciary~~and ~~duties~~expenses ~~related~~and tosuch other relief as determined by the ~~clinical~~Court. On ~~trials~~September ~~for~~20, ~~OMONTYS~~2013, the Company and ~~for~~the ~~representations~~individual ~~regarding~~defendants (collectively, “Defendants”) filed a motion to dismiss the ~~Company's~~consolidated ~~business~~amended ~~health~~complaint. On November 19, ~~which~~2013, ~~was~~the ~~tied~~plaintiff filed her opposition to the ~~success~~motion to dismiss and on December 19, 2013, Defendants filed their reply in support of ~~OMONTYS~~their motion to dismiss. The ~~lawsuits~~hearing ~~also~~on ~~asserts~~the ~~claims~~motion ~~for~~to ~~unjust~~dismiss ~~enrichment~~occurred on January 15, 2014. On January 21, 2014, the Court issued its order granting the motion to dismiss regarding violations of Section 20(a) against all Defendants and ~~corporate~~it ~~waste~~granted the motion to dismiss in part, denying the motion to dismiss in part, and providing plaintiffs with an opportunity to amend the complaint. On February 18, 2014, the Court, pursuant to a stipulation by the parties, stayed the litigation for ninety days to allow the parties to conduct settlement discussions.

Additional complaints may be filed against us and our directors and officers related to our recall of OMONTYS.

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Product Liability Litigation

On or about February 13, 2014, a complaint was filed by an individual plaintiff in the Fourth Judicial District Court (Ouachita Parish) of the State of Louisiana, naming as defendants the Company, Takeda Pharmaceuticals America, Inc., Takeda Pharmaceuticals U.S.A., Inc., Takeda Development Center Americas, Inc., Takeda Pharmaceuticals International, Inc., Takeda Pharmaceutical Company Limited, Fresenius Medical Care Monroe, LLC, and Fresenius Medical Care Holdings, Inc., and indicating an intention to add two physicians as defendants. The plaintiff seeks to hold the defendants liable in connection with the death of her husband on February 15, 2013. The complaint alleges that the Company and certain other defendants are liable under the Louisiana Products Liability Act, La.R.S. 9:2800.51, et seq., other Louisiana statutes, and otherwise in connection with their alleged acts and omissions with respect to OMONTYS. The plaintiff seeks various categories or types of damages, including, without limitation, damages for her and her late husband’s alleged losses and injuries, punitive or exemplary damages, the price of OMONTYS and reasonable expenses occasioned by the sale of that drug, and other relief as set forth in the complaint. We are continuing to review the complaint with our partner, Takeda and there can be no assurances that additional products liability complaints will not be brought.

Item 4. Mine Safety Disclosures

Not applicable.

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PART II.

Item 5. Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

Market For Our Common Stock

~~Our~~Since June 6, 2013 our common stock ~~has~~is ~~been~~currently traded on the ~~NASDAQ~~Over ~~Stock~~The Counter Electronic Market (OTCQB) under the symbol "AFFY". Prior ~~since~~to ~~December 15~~June 6, ~~2006.~~2013, our common stock was traded on the NASDAQ Global Select Market. As of February 28, ~~2013~~2014, there were approximately 7976 holders of record of our common stock. The following table sets forth, for the periods indicated, the range of high and low intraday sales prices of our common stock as quoted on the NASDAQ Global Select Market and Over The Counter Electronic Market.



	High	Low
2013
4th Quarter	$1.33	$0.76
3rd Quarter	$1.99	$0.96
2nd Quarter	$2.08	$0.80
1st Quarter	$21.56	$1.05



	High	Low
2012
4th Quarter	$27.74	$18.28
3rd Quarter	$22.00	$11.73
2nd Quarter	$14.95	$10.86
1st Quarter	$16.25	$6.35

	High	Low
2011
4th Quarter	$8.45	$4.14
3rd Quarter	$8.00	$3.93
2nd Quarter	$7.50	$5.82
1st Quarter	$8.50	$5.79

The closing price for our common stock as reported by the Over The Counter Market on March 12, 2014 was $0.89 per share.

The closing price for our common stock as reported by the NASDAQ Global Select Market on February 28, 2013 was $2.65 per share.

Dividend Policy

We have never declared or paid any cash dividends on our common stock~~. We~~ ~~currently expect to retain any future earnings for use in the operation of our business~~ and do not anticipate paying any cash dividends on our common stock in the foreseeable future. In March 2012, we entered into a Loan and Security Agreement, or Loan and Security Agreement, with Oxford Finance LLC or Oxford and Silicon Valley Bank, which requires we obtain prior written consent from the lenders before we pay dividends (other than dividends payable solely in capital stock) or make any distribution or payment in respect of any capital stock.

Recent Sales of Unregistered Securities

Except as previously reported in our quarterly reports on Form 10-Q filed with the SEC during the year ended December 31, ~~2012~~2013, there were no unregistered sales of equity securities by us during the year ended December 31, ~~2012~~2013.

Issuer Purchases of Equity Securities

We did not repurchase any of our equity securities during the fourth quarter of the year ended December 31, ~~2012~~2013.

Performance Graph(1)

The following graph shows the total stockholder return of an investment of $100 in cash on December 31, 2007, through December 31, ~~2012~~2013 for (i) our common stock, (ii) the Nasdaq Composite Index (U.S.) and (iii) the Nasdaq Biotechnology Index as of December 31, ~~2012~~2013. Pursuant to applicable Securities and Exchange Commission rules, all values assume reinvestment of the full amount of all dividends, however no dividends have been declared on our common stock to date. The stockholder return shown on the graph below is not necessarily indicative of future performance, and we do not make or endorse any predictions as to future stockholder returns.

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COMPARISON OF 5 YEAR CUMULATIVE TOTAL RETURN*

Among Affymax Inc., the NASDAQ Composite Index, and the NASDAQ Biotechnology Index

_______________________________________________________________________________

*$100 invested on 12/31/0708 in stock or index, including reinvestment of dividends.

Fiscal year ending December 31.

____________________________________________________________________________


(1)	This Section is not "soliciting material," is not deemed "filed" with the Commission and is not to be incorporated by reference into any filing of Affymax, Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date hereof and irrespective of any general incorporation language in any such filing.

Item 6. Selected Financial Data.

The following selected financial data should be read together with our audited financial statements and accompanying notes and "Management's Discussion and Analysis of Financial Condition and Results of Operations" section and other financial information included in this Annual Report on Form 10-K. The selected financial data in this section is not intended to replace our audited financial statements and the accompanying notes. Our historical results are not necessarily indicative of our future results.

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	Year ended December 31,
	2012			2011			2010			2009			2008
	2013			2012			2011			2010			2009
	(in thousands, except per share data)
Statements of Operations Data:
Revenue:
Collaboration revenue	$	941,~~358~~364		$	4794,~~703~~358		$	~~112~~47,~~503~~703		$	~~114~~112,~~883~~503		$	82114,~~162~~883
License and royalty revenue	125			1712			1817			1618			~~689~~16
Total revenue	941,~~370~~369			4794,~~720~~370			~~112~~47,~~521~~720			~~114~~112,~~899~~521			82114,~~851~~899
Operating expenses:
Impairment of inventory and losses under firm purchase commitments	~~44,957~~—			—44,957			—			—			—
Research and development	5111,~~738~~857			7651,~~308~~738			9376,~~638~~308			~~157~~93,~~125~~638			~~137~~157,~~492~~125
Selling, general and administrative	8927,~~714~~529			3289,~~818~~714			3332,~~331~~818			3633,~~716~~331			3436,~~090~~716
Total operating expenses	186,409			109,126			126,969			193,841			171,582
Collaboration cost reimbursement	(43,451		)	—			—			—			—
Loss from operations	(92,039		)	(61,406		)	(14,448		)	(78,942		)	(88,731		)
Impairment (gain on disposal) of prepaid expenses, fixed assets and intangible assets	4,414			—			—			—			—
Interest income	77			169			275			934			4,545
2013 Restructuring charge	16,066			—			—			—			—
Interest expense	(1,442		)	(144		)	(140		)	(105		)	(609		)
Total operating expenses	16,415			186,409			109,126			126,969			193,841
Other income (expense), net	(34		)	15			239			171			(1,433		)
Loss from operations	(15,046		)	(92,039		)	(61,406		)	(14,448		)	(78,942		)
Loss before provision (benefit) for income taxes	(93,438		)	(61,366		)	(14,074		)	(77,942		)	(86,228		)
Interest income	21			77			169			275			934
Provision (benefit) for income taxes	(26		)	1			1			(1,411		)	282
Interest expense	(1,565		)	(1,442		)	(144		)	(140		)	(105		)
Net loss	$	(93,412	)	$	(61,367	)	$	(14,075	)	$	(76,531	)	$	(86,510	)
Other income (expense), net	8			(34		)	15			239			171
Loss before provision (benefit) for income taxes	(16,582		)	(93,438		)	(61,366		)	(14,074		)	(77,942		)
Provision (benefit) for income taxes	(2,158		)	(26		)	1			1			(1,411		)
Net loss	$	(14,424	)	$	(93,412	)	$	(61,367	)	$	(14,075	)	$	(76,531	)
Net loss per common share:
Basic and diluted (1)	$	(20.5739	)	$	(12.8457	)	$	(01.5784	)	$	(40.0657	)	$	(54.6806	)
Weighted-average number of common shares used in computing basic and diluted net loss per loss common share	3637,~~342~~448			3336,~~288~~342			2433,~~488~~288			1824,~~865~~488			1518,~~220~~865

	December 31,
	2012			2011			2010			2009			2008
	2013			2012			2011			2010			2009
	(in thousands)
Balance Sheet Data:
Cash, cash equivalents and short-term investments	$	775,~~982~~597		$	9877,~~504~~982		$	9798,~~081~~504		$	~~160~~97,~~588~~081		$	94160,~~719~~588
Receivable from Takeda	~~18,365~~—			618,~~937~~365			—6,937			~~18,561~~—			2118,~~688~~561
Long-term investments	~~2,323~~—			—2,323			~~19,876~~—			719,~~978~~876			227,~~945~~978
Total assets	~~118~~7,~~217~~443			118,~~995~~217			~~131~~118,~~387~~995			~~211~~131,~~510~~387			~~167~~211,~~720~~510
Payable to Takeda	—			—			~~5,958~~—			—5,958			—
Deposit from Takeda	~~559~~—			~~1,998~~559			—1,998			—			—
Advance from Takeda	278,~~715~~189			627,~~121~~715			—6,121			—			—
Notes payable	~~8,844~~—			—8,844			—			—			—
Accumulated deficit	(~~543~~558,~~713~~137		)	(~~450~~543,~~301~~713		)	(~~388~~450,~~934~~301		)	(~~374~~388,~~859~~934		)	(~~298~~374,~~328~~859		)
Total stockholders' equity	8,281			75,997			72,547			66,905			8,984
Total stockholders' equity (deficit)	$	(1,428	)	$	8,281		$	75,997		$	72,547		$	66,905

_______________________________________________________________________________


(1)	Please see Note 2 of Notes to Financial Statements for an explanation of the method used to calculate the net loss per common share and the number of shares used in the computation of the per share amounts.

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Overview

We are a biopharmaceutical company ~~committed~~in ~~to discovering, developing and delivering innovative therapies that improve~~ the ~~lives~~process of ~~patients~~restructuring ~~with kidney disease and other serious and often life-threatening illnesses~~operations. In March 2012, the U.S. Food and Drug Administration, or FDA, approved ~~our~~the Company’s first and only product, OMONTYS® (peginesatide) Injection for the treatment of anemia due to chronic kidney disease in adult patients on dialysis. OMONTYS is a synthetic, peptide-based erythropoiesis stimulating agent, or ESA, designed to stimulate production of red blood cells~~. Our~~ ~~product~~and ishas been the only once-monthly ESA ~~that has been~~ available to the adult dialysis patient population in the U.S. In We ~~2012, we~~ co-commercialized OMONTYS ~~in the U.S.~~ with our collaboration partner, Takeda Pharmaceutical Company Limited, or Takeda during 2012 until February 2013, when we and Takeda announced a nationwide voluntary recall of OMONTYS as a result of safety concerns. Effective April 1, 2013, we entered into an amendment of our collaboration agreement with Takeda pursuant to which Takeda assumed full responsibility for OMONTYS, including responsibility for the ~~largest~~ongoing ~~pharmaceutical~~recall ~~company~~and investigation with the FDA, and we granted them an exclusive license to OMONTYS in ~~Japan~~consideration for potential royalties and milestones.

InRestructuring early 2013 and in consultation with the FDA, we and Takeda voluntarily recalled OMONTYS nationwide from the market as a result of post-marketing reports regarding serious hypersensitivity reactions, including anaphylaxis, which can be life-threatening or fatal. In connection with the recall, we and Takeda suspended all promotional and marketing activities for OMONTYS. While we continue to investigate the potential cause of the safety concerns at this time, we face significant challenges to our business. We are unable to estimate the scope or timelines associated with the investigation, which may be costly and time-consuming, and with our limited funds and resources, we may not be able to complete the investigation or ever identify the causes of the safety concerns.

In March 2013, we ~~undertook~~began implementing plans to ~~reorganize~~restructure our operations in order to reduce operating costs and focus on the OMONTYS safety and other related FDA issues associated with the recall of the product. InAs of December 31, 2013, in addition to transitioning many of the ongoing activities to our collaborator, Takeda, ~~our~~we ~~plans~~completed ~~include~~ a ~~significant~~ reduction in force of ~~approximately~~almost ~~230~~all ~~employees (75% of~~ our ~~workforce)~~personnel, including all of our commercial and medical affairs field forces as well as other employees throughout the organization. We ~~expect~~have torecorded ~~incur between~~ $816.01 million ~~and $10.0 million~~ in restructuring charges related to the workforce reduction during the ~~first~~year ~~quarter~~ended ofDecember 31, 2013. As a result of this restructuring and the recall, we ~~may~~ also ~~incur~~recorded ~~additional~~impairment charges ~~depending~~of on$4.4 ~~further~~million ~~review~~with ~~and~~respect ~~additional~~to ~~reductions~~our inproperty ~~operations~~and equipment and ~~may~~intangible ~~also~~assets ~~experience~~related ~~impairment~~to ~~changes~~our ~~with~~license ~~respect~~from toJanssen ~~our~~Biotech, ~~property~~Inc. ~~and~~(a ~~equipment~~subsidiary of Johnson & Johnson) and ~~long~~certain ~~lived~~of ~~assets~~its affiliated companies, collectively referred to as Janssen, in the ~~first~~year ~~quarter~~ended ofDecember 31, 2013.

WeIn ~~will~~April ~~continue~~2013, ~~to review our operations~~ as wepart ~~discuss with Takeda the roles and responsibilities~~ of ~~the~~our ~~parties~~efforts into ~~addressing~~restructure our ~~regulatory~~operations ~~and~~in ~~other~~order ~~obligations resulting from the OMONTYS recall. In any event, we plan~~ to ~~continue to make efforts to substantially~~ reduce ~~our operating~~ costs, ~~which will likely include further reductions~~ in ~~force~~addition ~~as we endeavor~~ to ~~conserve~~ our ~~cash~~reduction ~~resources. We have been~~ in ~~discussions with~~force, ~~and are planning to seek further assistance and support from Takeda as~~ we ~~transition~~engaged ~~from~~an aexperienced ~~commercial~~restructuring ~~operating~~firm, ~~company~~The toBrenner aGroup, ~~company potentially without any product~~Inc. WeWith ~~are~~the ~~undertaking~~engagement ~~steps to reduce all~~ of ~~our outstanding obligations to third parties and are dependent on those efforts to continue operations even in~~ the ~~near~~restructuring ~~term~~firm, ~~however,~~ we ~~may~~terminated ~~not be successful. We are particularly dependent on Takeda's willingness to continue~~ the ~~collaboration~~employment inof ~~a modified form that reduces~~ our ~~operating~~former ~~expenses~~executive ~~and responsibilities under the collaboration~~officers, ~~but~~including ~~we may also be required to reduce~~ our ~~share~~Chief ofExecutive ~~OMONTYS~~Officer ~~profits if~~ and ~~when~~Chief ~~the~~Financial ~~product may be re-introduced in the future~~Officer. Even if Takeda is willing to assume additional responsibilities under the collaboration, including the conduct of most or all of the ongoing investigation, the loss of critical personnel and functions means that we may ~~not be able to maintain our operations, support the New Drug Application or NDA, continue as a going concern or ever re-introduce OMONTYS.~~

InTakeda view of our limited resources and funds, we plan to explore various strategic alternatives, including a sale of the company or its assets or a corporate merger. We are considering all possible alternatives, including further restructuring activities, wind-down of operations or even bankruptcy proceedings. Amendment

IfEffective April 1, 2013, we and Takeda, ~~are~~collectively ~~unable~~the toParties, ~~rapidly~~entered ~~identify~~into ~~and rectify~~ the ~~causes~~Fourth ofAmendment, or the ~~safety~~Amendment, ~~concerns~~ to the ~~satisfaction~~February ~~of the FDA~~13, ~~which~~2006 isand ~~highly~~June ~~uncertain~~27, ~~OMONTYS~~2006 ~~may~~Collaboration beand ~~permanently~~License ~~withdrawn~~Agreements ~~from~~to amend and restate the ~~market. The~~ongoing ~~recall~~respective ofroles ~~OMONTYS~~and ~~has~~responsibilities ~~severely~~and ~~harmed~~related ~~our~~commitments ~~business,~~and financial ~~condition~~terms between the Parties, including the termination of the Collaboration and ~~prospects~~License Agreement dated as aof ~~going~~February ~~concern. The~~13, ~~recall~~2006, ~~has~~under ~~also~~which ~~limited~~we ~~our~~have ~~access~~granted toTakeda ~~funds~~a certain right and ~~the~~license ~~resources~~for ~~that~~the ~~may~~development beand ~~required~~commercialization in ~~order~~Japan toof ~~address~~OMONTYS, as amended by the ~~safety~~First ~~concerns. As~~Amendment, adated ~~result~~April 1, we2007, ~~may~~the beSecond ~~unable~~Amendment, todated ~~continue~~January ~~our~~1, ~~operations. In~~2008 ~~order~~and tothe ~~reintroduce~~Third ~~OMONTYS~~Amendment, wedated ~~would~~November ~~have~~7, to2011, ~~complete~~as ~~our~~well ~~ongoing~~as ~~thorough~~the ~~investigation~~related manufacturing supply, ~~identify~~safety, quality and co-promotion agreements between the ~~causes~~parties. The ofAmendment revised the ~~safety~~economics ~~concerns~~from ~~and~~a ~~provide~~profit-sharing arrangement to a ~~suitable~~milestone ~~plan~~and royalty-based compensation structure to ~~the~~us ~~FDA~~effective ~~for~~as ~~approval. Accordingly~~of April 1, ~~there~~2013. This ~~can~~Amendment beis nopart ~~assurance~~of ~~that~~our weongoing ~~can~~restructuring ~~address~~efforts resulting from the ~~safety~~voluntary ~~concerns~~recall ~~and~~announced ~~meet~~on February 23, 2013 related to OMONTYS, the ~~requirements~~suspension of U.S. marketing and promotional activities, and the ~~FDA~~ongoing ~~for~~investigation ~~reintroduction~~with the FDA. ~~Moreover,~~ The ~~even~~arrangement ifwith Takeda including the Amendment is referred to as the Arrangement.

34The Amendment effectuated a transfer of regulatory responsibilities, including the OMONTYS New Drug Application, or NDA, and all manufacturing, and development responsibilities from us to Takeda. Takeda received a worldwide, exclusive royalty-bearing license under our and joint Takeda-Affymax patents to develop, manufacture and commercialize OMONTYS.

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~~OMONTYS~~sales-based ~~could~~milestones, beand ~~reintroduced,~~(c) $150.0 million relates to sales-based milestones in amounts as previously disclosed outside of the ~~commercial~~U.S. ~~prospects~~but ~~for~~now ~~this~~including ~~product~~Japan ~~may~~as bea ~~permanently~~result ~~diminished~~of the Amendment and (ii) a potential development milestone payment of $5.0 million payable either upon regulatory approval in the ~~product~~E.U. ~~may~~or noJapan. The ~~longer~~royalties beare ~~commercially~~tiered ~~viable~~in the range of 13% to 17% with respect to net sales in the U.S. and in the range of 13% to 24% depending on the level of net sales by Takeda worldwide outside of the U.S.

InPrevious ~~March 2012, we entered into a loan and security agreement, or the Loan~~ Agreement, with ~~Oxford~~Takeda Finance LLC and Silicon Valley Bank, or, collectively, the Lenders, under which we may borrow up to a total of $30.0 million in two tranches. The first tranche of $10.0 million was borrowed in March 2012. The second tranche of $20.0 million was available for drawdown until March 31, 2013; however, it may no longer be available due to our recent recall of OMONTYS. In connection with the Loan Agreement, we issued the Lenders warrants to purchase 132,855 shares of our common stock, or the Warrants, which are exercisable at $11.855 per share. In September 2012, SVB Financial Group, the parent group of Silicon Valley Bank, exercised its Warrant for a net exercise of 23,453 shares of our common stock. In October 2012, Oxford Finance LLC exercised the remaining Warrants for a net exercise of 36,660 shares of common stock. Both of these Warrants were net exercised on a cashless basis. Since we suspended the marketing activities of OMONTYS and voluntarily recalled OMONTYS, we may be in breach under our Loan Agreement. The voluntary recall may be considered a material adverse event under the Loan Agreement. As a result, we have classified our loan balance as a current liability. Events of default under the Loan Agreement provide the Lenders with various rights, including the right to require immediate repayment of the outstanding principal plus accrued and unpaid interest through the prepayment date, the final payment of $0.5 million and the prepayment fee of $0.5 million. We have not received a notice of default. If we receive a notice of default from the Lenders, in addition to repaying the outstanding balance of our loan. we will also accrue the remaining final interest charge and the full amount of the final payment and the prepayment fee.

In 2012, we co-commercialized OMONTYS with Takeda. The commercial launch of the product occurred in April 2012. To commercialize OMONTYS, we established commercial and medical affairs infrastructures in 2012. The functions of our commercial and medical affairs infrastructures ~~include~~included marketing and sales, medical education, coverage and reimbursement and account management.

In 2012, we marketed our product primarily to dialysis organizations. Associated costs are included in selling, general and administrative costs or SG&A, in our accompanying financial statements.

In 2012, Takeda was responsible for account management, pricing and contracting. Specifically, Takeda had sole responsibility for invoicing and collection of receivables with regard to sales of OMONTYS. Takeda also ~~has~~had the rights and responsibility for establishing and modifying terms and conditions with customers with respect to the sale of OMONTYS in the U.S., including pricing discounts available to third-party payors, price adjustments and other allowable discounts and allowances. Both parties also ~~have~~had shared responsibilities such as joint marketing activities, business analytics and account management allocated by customer segments.

~~Outside~~Prior to the Amendment, outside of the U.S., Takeda holds an exclusive license to develop and commercialize OMONTYS and has primary responsibility for filing regulatory submissions and obtaining product approvals in those territories.

We ~~Revenues~~have inexperienced ~~2012,~~significant ~~2011~~operating ~~and~~losses ~~2010~~since ~~were derived almost exclusively from collaboration revenue from Takeda~~inception. ~~Collaboration~~ We ~~revenue~~have ~~consists~~funded ofour ~~milestone~~operations ~~payments,~~primarily ~~profit~~through ~~equalization~~the ~~revenue~~sale ~~related to our share~~ of ~~product~~equity ~~profit or loss on OMONTYS~~securities, reimbursement offor development ~~and commercialization~~ expenses, and ~~revenue for active pharmaceutical ingredient or~~ API production, ~~under~~license ~~our agreements with Takeda or collectively~~fees, ~~the Arrangement. We derived most of our collaboration revenue in 2012 from~~ milestone payments and profit equalization revenue~~. From~~ ~~inception~~from ~~to December 31~~Takeda, ~~2012,~~issuance ~~we have received $122.0 million~~ of ~~upfront~~notes ~~license fees~~payable, ~~$115.3~~capital ~~million in~~lease ~~milestone payments and $297.2 million related to the profit equalization revenue~~financings, ~~the~~interest ~~reimbursement~~earned ofon ~~development~~investments and ~~commercialization~~limited ~~expenses~~license fees and ~~purchase~~royalties offrom ~~API~~licensing ~~under~~intellectual ~~our Arrangement with Takeda~~property. WeAs ~~are~~of ~~eligible~~December 31, to2013, ~~receive~~we had an ~~aggregate~~accumulated deficit of $~~357~~558.01 million ~~in additional milestone payments from Takeda upon successful achievement of as yet unmet clinical development and regulatory milestones and sales-based milestones~~. ~~However, timing and amounts are extremely uncertain, due to the recall.~~

WeShareholder have experienced significant operating losses since inception. We have funded our operations primarily through the sale of equity securities, reimbursement for development expenses and API production, license fees, milestone payments and profit equalization revenue from Takeda, issuance of notes payable, capital lease financings, interest earned on investments and limited license fees and royalties from licensing intellectual property. As of December 31, 2012, we had an accumulated deficit of $543.7 million. However, due to the recent recall of OMONTYS described under the caption “OMONTYS Voluntary Recall” under “Item 1. Business” of this Annual Report on Form 10-K, we anticipate that we will incur substantial losses in future periods and may continue to incur substantial losses in the long term depending on our success in reintroducing and commercializing OMONTYS. Our operations have consumed substantial amounts of cash since our inception. If we are unable to identify quickly the causes of the OMONTYS safety concerns or raise additional funds when required or on acceptable terms, we may have to:Litigation

35On February 27, 2013, a securities class action complaint was filed in the United States District Court for the Northern District of California, naming as defendants the Company, certain of its officers, Takeda Pharmaceutical Company Limited, Takeda Pharmaceuticals U.S.A., Inc. and Takeda Global Research & Development Center, Inc. A second complaint naming the same defendants was filed on March 6, 2013. On May 2, 2013, the securities class action complaint that was filed on February 27, 2013 was voluntarily dismissed by the plaintiff. On May 21, 2013, the Court appointed a lead plaintiff in the remaining securities class action complaint that had been filed on March 6, 2013. On July 22, 2013, a consolidated amended class action complaint was filed on behalf of purported stockholders of the Company, naming as defendants the Company and certain of its former officers. The consolidated amended complaint alleges violations of Section 10(b) and 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder, in connection with allegedly false and misleading statements made by the defendants regarding OMONTYS, the Company's business practices, financial projections and other disclosures between August 8, 2012 and February 22, 2013, or the Class Period. The plaintiff seeks to represent a class comprised of purchasers of the Company's common stock during the Class Period and seeks damages, costs and expenses and such other relief as determined by the Court. On September 20, 2013, the Company and the individual defendants (collectively, “Defendants”) filed a motion to dismiss the consolidated amended complaint. On November 19, 2013, the plaintiff filed her opposition to the motion to dismiss and on December 19, 2013, Defendants filed their reply in support of their motion to dismiss. The hearing on the motion to dismiss occurred on January 15, 2014. On January 21, 2014, the Court issued its order granting the motion to dismiss regarding violations of Section 20(a) against all Defendants and it granted the motion to dismiss in part, denying the motion to dismiss in part, and providing plaintiffs with an opportunity to amend the complaint. On February 18, 2014, the Court, pursuant to a stipulation by the parties, stayed the litigation for ninety days to allow the parties to conduct settlement discussions.

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•Company's ~~abandon~~business ~~the~~health, ~~plan~~which was tied to ~~reintroduce~~the success of OMONTYS;. The lawsuits also assert claims for unjust enrichment and corporate waste. On May 31, 2013, the Court consolidated the two actions and appointed lead plaintiff. On June 11, 2013, lead plaintiff designated the complaint filed on March 29, 2013 as the operative complaint. On August 6, 2013, the Court stayed the State Court Derivative Action pending the outcome of the motion to dismiss in the securities class action. Subsequent to the order regarding the motion to dismiss in the securities class action, on January 31, 2014, the Court ordered that the State Court Derivative Action be stayed in its entirety until resolution of the securities class action.

• On ~~assume~~August ~~greater~~19, ~~risks~~2013, another derivative lawsuit was filed purportedly on behalf of the Company in the United States District Court for the Northern District of California naming certain of our current and ~~significantly~~former ~~delay~~officers and directors as defendants (the “Federal Derivative Action”). The lawsuit’s allegations are substantially similar to the allegations in the State Court Derivative Action. On October 21, ~~scale~~2013, ~~back~~the Court ordered a stay in the Federal Derivative Action pending the outcome of the motion to dismiss in the securities class action. Subsequent to the order regarding the motion to dismiss in the securities class action, oron ~~discontinue~~January ~~operations;~~31, 2014, the Court ordered that the Federal Derivative Action be stayed until resolution of the securities class action.

• Additional ~~relinquish~~complaints ~~some~~may orbe ~~all~~filed ofagainst us and our ~~existing~~directors ~~rights~~and officers related to our recall of OMONTYS;.

•Product ~~eliminate~~Liability ~~or defer manufacturing efforts that may negatively impact OMONTYS; or~~Litigation

•On ~~pursue~~or ~~alternatives~~about ~~such~~February as13, 2014, a ~~restructuring~~complaint was filed by an individual plaintiff in the Fourth Judicial District Court (Ouachita Parish) of the State of Louisiana, naming as defendants the Company, Takeda Pharmaceuticals America, Inc., Takeda Pharmaceuticals U.S.A., Inc., Takeda Development Center Americas, Inc., Takeda Pharmaceuticals International, Inc., Takeda Pharmaceutical Company Limited, Fresenius Medical Care Monroe, LLC, and Fresenius Medical Care Holdings, Inc., and indicating an intention to add two physicians as defendants. The plaintiff seeks to hold the defendants liable in connection with the death of her husband on February 15, 2013. The complaint alleges that the Company and certain other defendants are liable under the Louisiana Products Liability Act, La.R.S. 9:2800.51, et seq., other Louisiana statutes, and otherwise in connection with their alleged acts and omissions with respect to OMONTYS. The plaintiff seeks various categories or ~~winddown~~types of ~~operations~~damages, including, without limitation, damages for her and her late husband’s alleged losses and injuries, punitive or exemplary damages, the price of OMONTYS and reasonable expenses occasioned by the sale of that drug, and other relief as set forth in the complaint. We are continuing to review the complaint with our partner, Takeda and there can be no assurances that additional products liability complaints will not be brought.

On February 27, 2013, a securities class action complaint was filed in the United States District Court for the Northern District of California, naming as defendants Affymax, Inc. or the Company, certain of its officers, Takeda Pharmaceutical Company Limited, Takeda Pharmaceuticals U.S.A., Inc. and Takeda Global Research & Development Center, Inc. A second complaint naming the same defendants was filed on March 6, 2013. The complaints, filed on behalf of purported stockholders of the Company, allege violations of Section 10(b) and 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder, in connection with allegedly false and misleading statements made by the defendants regarding the Company's business practices, financial projections and other disclosures between December 8, 2011 and February 22, 2013, or the Class Period. The plaintiff seeks to represent a class comprised of purchasers of the Company's common stock during the Class Period and seeks damages, costs and expenses and such other relief as determined by the Court. On March 19, 2013, a derivative lawsuit was filed purportedly on behalf of the Company in California Superior Court for the County of Santa Clara naming certain of our officers and directors as defendants. The lawsuit alleges that certain of the Company's officers and directors breached their fiduciary duties related to the clinical trials for OMONTYS and for representations regarding the Company's business health, which was tied to the success of OMONTYS. The lawsuits also asserts claims for unjust enrichment and corporate waste. Additional complaints may be filed against us and our directors and officers related to our recall of OMONTYS. Our management believes that we have meritorious defenses and intends to defend these lawsuits vigorously. However, these lawsuits are subject to inherent uncertainties, the actual cost may be significant, and we may not prevail. We believe we are entitled to coverage under our relevant insurance policies, subject to a retention, but coverage could be denied or prove to be insufficient.

We expect to continue to incur substantial operating losses as we investigate the cause of these safety concerns to OMONTYS, search for and implement solutions to address it and prepare for the potential reintroduction of OMONTYS as well as share in those efforts of Takeda's. When and if we reintroduce OMONTYS, we expect to incur additional operating losses as we add infrastructure and operations to support commercialization of OMONTYS, and potentially begin new R&D programs. Our ability to generate product sales and become profitable depends heavily on our ability to successfully reintroduce and commercialize OMONTYS. OMONTYS will require significant marketing efforts and substantial investment before it can provide us or our partners with any meaningful revenue. Accordingly, we may never generate significant revenues and, even if we do generate revenue in the future, we may never achieve or sustain profitability.

As a result of the February 23, 2013 nationwide voluntary recall of OMONTYS and the suspension of all marketing activities, there is significant uncertainty as to whether we will have sufficient existing cash, cash equivalents and investments to fund our operations for the next 12 months. If we were to reduce cash outflows, there is no assurance that we will be able to reduce our operating expenses enough to meet our existing obligations. If we are not able to reintroduce the product or obtain additional funding in the near future, our cash resources will rapidly be depleted and we will be required to materially reduce or suspend operations, which would likely have a material adverse effect on our business, stock price and our relationships with third parties with whom we have business relationships, at least until additional funding is obtained. If we do not have sufficient funds to continue operations, we could be required to liquidate our assets, seek bankruptcy protection or other alternatives that would likely result in receiving less than the value at which those assets are carried on our financial statements, and it is likely that investors will lose all or some of their investment in us. Any failure to dispel any continuing doubts about our ability to continue as a going concern could adversely affect our ability to enter into collaborative relationships with business partners, make it more difficult to obtain required financing on favorable terms or at all, negatively affect the market price of our common stock and could otherwise have a material adverse effect on our business, financial condition and results of operations.

If the recall is not lifted and we are not able to reintroduce OMONTYS, this will result in a severe decrease to our profit equalization revenue in future periods. Even if we are successful in reintroducing and commercializing OMONTYS in the future, there can be no assurance that revenues will ramp up rapidly enough to offset operating losses and repayment of debts. Further challenges or delays to potential reintroduction and commercialization of OMONTYS may require us to raise additional funding to successfully reintroduce and commercialize OMONTYS. We may seek to raise additional funds through public or private financing, strategic partnerships or other arrangements. Any additional equity financing would be dilutive to

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stockholders and debt financing, if available, may involve restrictive covenants that may limit our ability to conduct our business and increase our risk of defaults. The market may take into consideration of the recent recall of OMONTYS, which recall is described under the caption “OMONTYS Voluntary Recall” in “Item 1. Business” of this Annual Report on Form 10-K which may negatively affect our ability to obtain additional funding. Market conditions may significantly limit our ability to raise funds such that there can be no assurance we can raise the additional funds to support our continuing operations, and successfully reintroduce and commercialize OMONTYS, and funding may not be available to us on acceptable terms, or at all.

Results of Operations

Revenue

During the commercialization period, which commenced in June 2011, and ended in the first half of 2013, we ~~receive~~received reimbursement for certain collaboration expenses. Takeda ~~bears~~was ~~responsibility~~responsible for 70% of third-party expenses related to U.S. development and 50% of third party expenses related to the commercialization of OMONTYS in the U.S. incurred by us and we ~~are~~were responsible for the reciprocal amount of development and commercialization expenses. Certain employee-related expenses supporting preparation for commercialization of OMONTYS in the U.S. ~~are~~were also shared equally. Such employee-related costs include the cost of certain employees that are required to commercialize OMONTYS such as field sales representatives, sales operations, medical science liaisons, nurse educators, conversion specialists, national accounts managers and reimbursement specialists. In addition, costs of employees in clinical, regulatory and other development functions supporting any post-marketing development activity required by the FDA or separately agreed to by the parties in the U.S. are generally shared equally.

During the development period under the Arrangement with Takeda, which ended in May 2011 upon the submission of our NDA to the FDA for review, collaboration revenue was recognized using the Contingency Adjusted Performance Model, or CAPM. As a result, any payments from Takeda under the Arrangement were recorded as deferred revenue and recognized ratably over the estimated development period. Prior to the approval of OMONTYS, collaboration revenue had consisted of reimbursement of development and commercial expenses, net of Takeda's own eligible expenses, and milestone payments.

OMONTYS sales by Takeda commenced in September 2012. Subsequent to the launch of OMONTYS and recognition of product revenue by Takeda, our collaboration revenue consisted of profit equalization revenue generated from our collaboration agreement with Takeda, milestone payments, reimbursements of certain eligible development and commercial expenses, net of Takeda's own eligible expenses, and revenue previously deferred related to payments we received associated with previously expensed API, which have been sold by Takeda. Revenue from profit equalization is calculated on a quarterly basis as the amount required so that the profit or loss realized by both Affymax and Takeda on OMONTYS equates to 50% of the total product profit or loss. Total product profit or loss on OMONTYS is calculated as gross product sales recorded by Takeda, less the following deductions recorded by Takeda: rebates and discounts, cost of goods and other gross-to-net adjustments incurred by Takeda, royalty expense incurred by us, commercialization expenses (full-time equivalents or FTE, related and out of pocket costs) incurred by both Takeda and us, and certain development costs associated with post-marketing development activities (FTE related and out of pocket costs) incurred by both Takeda and us.35

Revenue as compared to prior years is as follows (in thousands):

	Year ended December 31,						Percent Change
	2012		2011		2010		2012/2011		2011/2010
Collaboration revenue	$	94,358	$	47,703	$	112,503	98	%	(58	)%
License and royalty revenue	12		17		18		(29	)%	(6	)%
Total revenue	$	94,370	$	47,720	$	112,521	98	%	(58	)%

Revenue increased $46.7 million from $47.7 million in 2011 to $94.4 million in 2012. The increase in collaboration revenue for the year ended December 31, 2012 compared to the year ended December 31, 2011 was primarily due to the recognition of $60.3 million in milestone payments from Takeda related to FDA approval of OMONTYS, the European Medicines Agency, or EMA’s acceptance for review of the Marketing Authorization Application or MAA submitted by Takeda, and commercial progress on the OMONTYS product launch and our profit equalization revenue(1) related to the commencement of OMONTYS sales, and revenue previously deferred related to previously expensed API, which is partially offset by a decrease in amounts eligible for reimbursement under our Arrangement with Takeda.

Revenues decreased $64.8 million from $112.5 million in 2010 to $47.7 million in 2011. The decrease in collaboration revenue for the year ended December 31, 2011 compared to the year ended December 31, 2010 was due to a reduction in overall research and development or R&D costs eligible for reimbursement under our collaboration with Takeda as we completed our

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~~Phase 3~~over ~~clinical~~the ~~trials~~estimated indevelopment ~~early 2010~~period. ~~Collaboration~~Prior ~~revenue~~to ~~for~~ the ~~year~~approval ~~ended~~of ~~December 31~~OMONTYS, ~~2010~~collaboration ~~was~~revenue ~~also~~had ~~impacted~~consisted byof ~~our~~reimbursement ~~change in estimate adjustment recorded in the fourth quarter~~ of ~~2010~~development ~~related to our clinical trial expense which reduced revenue by $7.8 million. These decreases were partially offset by milestone payments received from Takeda in 2011~~ and ~~2010. During~~commercial ~~the year ended December 31~~expenses, ~~2011,~~net weof ~~received a $10.0 million cash milestone payment from~~ Takeda's ~~for~~own ~~acceptance~~eligible ~~for review of our NDA by the FDA in the third quarter of 2011. For the year ended December 31~~expenses, ~~2010, we received a $5.0 million milestone payment from Takeda for the initiation of Phase 3 renal indication in Japan in March 2010~~ and ~~$30.0 million in~~ milestone payments ~~for the database lock of our non-dialysis and dialysis Phase 3 trials in the second quarter of 2010~~. ~~Both of these milestones were accounted for under CAPM.~~

OMONTYS sales commenced in September 2012. Subsequent to the launch of OMONTYS and recognition of product revenue by Takeda, our collaboration revenue consisted of profit equalization revenue generated from our collaboration agreement with Takeda, milestone payments, reimbursements of certain eligible development and commercial expenses, net of Takeda's own eligible expenses, and revenue previously deferred related to payments we received associated with previously expensed API, which have been sold by Takeda. Revenue from profit equalization was calculated on a quarterly basis as the amount required so that the profit or loss realized by both Affymax and Takeda on OMONTYS equates to 50% of the total product profit or loss. Total product profit or loss on OMONTYS was calculated as gross product sales recorded by Takeda, less the following deductions recorded by Takeda: rebates and discounts, cost of goods and other gross-to-net adjustments incurred by Takeda, royalty expense incurred by us, commercialization expenses (full-time equivalents or FTE, related and out of pocket costs) incurred by both Takeda and us, and certain development costs associated with post-marketing development activities (FTE related and out of pocket costs) incurred by both Takeda and us.

In February 2013, we and Takeda announced a nationwide voluntary recall of OMONTYS as a result of safety concerns. Effective April 1, 2013, we entered into an amendment of our collaboration agreement with Takeda pursuant to which Takeda assumed full responsibility for OMONTYS, including responsibility for the ongoing recall and investigation with the FDA, and we granted them an exclusive license to OMONTYS in consideration for potential royalties and milestones.

Revenue as compared to prior years is as follows (in thousands):



	Year ended December 31,						Percent Change
	2013		2012		2011		2013/2012		2012/2011
Collaboration revenue	$	1,364	$	94,358	$	47,703	(99	)%	98	%
License and royalty revenue	5		12		17		(58	)%	(29	)%
Total revenue	$	1,369	$	94,370	$	47,720	(99	)%	98	%

Revenue decreased $(93.0) million from $94.4 million in 2012 to $1.4 million in 2013. The decrease was due to the cessation of sales of OMONTYS upon the recall in February 2013. There have been no further sales of OMONTYS since the recall.

Revenues increased $46.7 million from $47.7 million in 2011 to $94.4 million in 2012. The increase in collaboration revenue for the year ended December 31, 2012 compared to the year ended December 31, 2011 was primarily due to the recognition of $60.3 million in milestone payments from Takeda related to FDA approval of OMONTYS, the European Medicines Agency, or EMA’s acceptance for review of the Marketing Authorization Application or MAA submitted by Takeda, and commercial progress on the OMONTYS product launch and our profit equalization revenue⁽¹⁾ related to the commencement of OMONTYS sales, and revenue previously deferred related to previously expensed API, which is partially offset by a decrease in amounts eligible for reimbursement under our Arrangement with Takeda.

The following table presents our collaboration revenue, by revenue type, for the periods presented (in thousands):

	Year ended December 31,
	2012		2011		2010
	2013		2012		2011
Profit equalization revenue (1)	$	~~26,544~~5	$	—26,544	$	—
Milestone payments	~~60,250~~—		1060,~~000~~250		—10,000
Revenue previously deferred related to API	~~936~~—		—936		—
Revenue recognized under CAPM	—		~~26,606~~—		~~112~~26,~~503~~606
Net expense reimbursement after CAPM	61,~~628~~364		116,~~097~~628		—11,097
Total collaboration revenue	$	941,~~358~~369	$	4794,~~703~~358	$	~~112~~47,~~503~~703

^{______________________________________________________}

(1) Revenue from profit equalization is calculated on a quarterly basis as the amount required such that the profit or loss realized by both Affymax and Takeda on the product equates to 50% of the total product profit or loss. Total product profit or loss on OMONTYS is calculated as gross product sales recorded by Takeda, less the following deductions also recorded by Takeda: rebates and discounts, cost of goods, and other gross-to-net adjustments incurred by Takeda; royalty expense incurred by us, commercialization expenses (FTE related and out of pocket costs) incurred by both Takeda and us, and certain development costs associated with post-marketing development activities (FTE related and out of pocket costs) incurred by both Takeda and us. Profit equalization revenue is recognized as revenue in the period product revenue is recognized by Takeda.

On February 23, 2013, we and Takeda announced a nationwide voluntary recall of OMONTYS as a result of postmarketing reports regarding safety concerns, including anaphylaxis, which can be life-threatening or fatal. We and Takeda are actively investigating the cause of these reactions but there can be no assurance that a solution will be found. As a result of the voluntary recall of OMONTYS, all marketing activities have been suspended and there is significant uncertainty as to when or if we will be able to reintroduce OMONTYS. Although we still maintain a license and are actively exploring a cause for the allergic reactions, we do not know when this reintroduction will occur, if at all. If the recall is not lifted and we are not able to reintroduce OMONTYS, this will result in a severe decrease to our profit equalization revenue or potentially profit equalization losses in future periods. The total estimated product returned in the recall all relates to product shipped subsequent to December 31, 2012; as a result there was no impact to the 2012 profit equalization revenue resulting from the recall. Given the uncertainty of any profit equalization revenue in future periods, we have recharacterized our deferred revenue as an Advance from Takeda, which is reflected as a current liability in our December 31, 2012 financial statements. Additionally, although we are eligible to receive future milestones from Takeda, timing and amounts of future milestone payments, if any, are extremely uncertain due to the recall.36

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costs associated with post-marketing development activities (FTE related and out of pocket costs) incurred by both Takeda and us. Profit equalization revenue is recognized as revenue in the period product revenue is recognized by Takeda.

Takeda Amendment

On February 23, 2013, we and Takeda announced a nationwide voluntary recall of OMONTYS as a result of post marketing reports regarding safety concerns, including anaphylaxis, which can be life-threatening or fatal. As a result of the voluntary recall of OMONTYS, all marketing activities were suspended and sales were ceased.

Effective April 1, 2013, we and Takeda, collectively the Parties, entered into the Fourth Amendment, or the Amendment, to the February 13, 2006 and June 27, 2006 Collaboration and License Agreements to amend and restate the ongoing respective roles and responsibilities and related commitments and financial terms between the Parties, including the termination of the Collaboration and License Agreement dated as of February 13, 2006, under which we have granted Takeda a certain right and license for the development and commercialization in Japan of OMONTYS, as amended by the First Amendment, dated April 1, 2007, the Second Amendment, dated January 1, 2008 and the Third Amendment, dated November 7, 2011, as well as the related manufacturing supply, safety, quality and co-promotion agreements between the parties. The Amendment revised the economics from a profit-sharing arrangement to a milestone and royalty-based compensation structure to us effective as of April 1, 2013. This Amendment is part of our ongoing restructuring efforts resulting from the voluntary recall announced on February 23, 2013 related to OMONTYS, the suspension of U.S. marketing and promotional activities, and the ongoing investigation with the FDA. The arrangement with Takeda including the Amendment is referred to as the Arrangement.

The Amendment effectuated a transfer of regulatory responsibilities, including the OMONTYS New Drug Application, or NDA, and all manufacturing, and development responsibilities from us to Takeda. Takeda received a worldwide, exclusive royalty-bearing license under our and joint Takeda-Affymax patents to develop, manufacture and commercialize OMONTYS.

Operating expenses incurred by us which have been subject to reimbursement by Takeda under the Arrangement, excluding API manufacturing costs are as follows (in thousands):

	Year ended December 31,
	2012		2011		2010
	2013		2012		2011
Research & development	$	~~15,480~~525	$	2215,~~412~~480	$	3522,~~305~~412
Selling, general & administrative	~~43,748~~—		843,~~471~~748		8,~~241~~471
Total	$	~~59,228~~525	$	3059,~~883~~228	$	4330,~~546~~883

~~The~~Due ~~change~~to in the ~~mix~~recall of ~~costs~~OMONTYS ~~subject~~all toactivities ~~reimbursement~~related ~~in 2012 compared~~ to ~~2011~~the ~~was~~product ~~primarily~~which ~~due~~were toperformed ~~our~~by ~~company~~Affymax ~~shifting~~were ~~from~~transferred ~~being~~to aTakeda ~~R&D~~per ~~company~~the tofourth ~~now~~amendment ~~becoming~~of athe ~~commercial~~license ~~company~~agreement. In ~~2012,~~The wereimbursements ~~commercially~~received ~~launched OMONTYS which resulted~~ in ~~much~~2013 ~~larger~~were ~~commercial-related~~for ~~reimbursements. In~~payroll ~~2011,~~costs ~~our~~incurred ~~primary~~by ~~focus~~Affymax ~~was~~employees ~~obtaining FDA approval which was more R&D-related. We expect collaboration revenue~~ to ~~fluctuate~~assist ~~with changes~~ in ~~revenue related to~~ the ~~profit~~transition ~~equalization~~ of ~~the~~those ~~collaboration and with changes in the amount of reimbursable expenses for our direct development~~activities. ~~Revenue/~~

38The change in the mix of costs subject to reimbursement in 2012 compared to 2011 was primarily due to our company shifting from being a R&D company to a commercial company. In 2012, we commercially launched OMONTYS which resulted in much larger commercial-related reimbursements. In 2011, our primary focus was obtaining FDA approval which was more R&D-related. We expect collaboration revenue to fluctuate with changes in revenue related to the profit equalization of the collaboration and with changes in the amount of reimbursable expenses for our direct development. Revenue/loss from profit equalization is influenced by a number of factors, some of which may impact the sales of OMONTYS and reimbursement of collaboration expenses more significantly than others, including, but not necessarily limited to, our ability to reintroduce OMONTYS following the February 2013 recall and the level of reimbursable costs incurred by us versus those incurred by Takeda including costs associated with the recall, costs of the investigation and potential write offs of API or drug product

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loss from profit equalization is influenced by a number of factors, some of which may impact the sales of OMONTYS and reimbursement of collaboration expenses more significantly than others, including, but not necessarily limited to, our ability to reintroduce OMONTYS following the February 2013 recall and the level of reimbursable costs incurred by us versus those incurred by Takeda including costs associated with the recall, costs of the investigation and potential write offs of API or drug product inventory by Takeda. We do not expect an income statement charge for these as we believe that our exposure is adequately covered under our Advance from Takeda as of December 31, 2012. Although we are eligible to receive future milestones from Takeda, timing and amounts are extremely uncertain due to the recall.

Cost of Manufacturing API for the Collaboration

The cost of manufacturing API is not reflected in our statement of ~~operations~~comprehensive (loss) income as we ~~are~~were reimbursed by Takeda for all costs we ~~incur~~incurred with third parties. At the time of FDA approval in March 2012, we had produced approximately $20.5 million of commercial grade API that had been expensed previously as R&D expenses. As of December 31, 2012, ~~all~~we had a remaining balance of ~~the~~$17.8 million in deferred revenue related to previously expensed API ~~has been~~ shipped to Takeda,. As a result of ~~which~~the werecall, ~~have~~the ~~already~~remaining ~~been~~balance ~~reimbursed~~of ~~$18.4~~deferred ~~million~~revenue byhas ~~Takeda~~been ~~and~~reversed ~~have~~during athe ~~receivable~~year ~~for~~ended ~~the~~December ~~remaining~~31, ~~balance~~2013.

Revenue in the year ended December 31, 2012 was benefited by API material previously expensed. Our collaboration revenue related to API for the year ended December 31, 2012 was $0.9 million, compared to $0.2 million that would have been recorded as revenue if the API were not previously expensed. As of December 31, 2012, we had a remaining balance of $17.8 million in deferred revenue related to previously expensed API. Given the uncertainty of any profit equalization revenue in future periods we have recharacterized our deferred revenue as an Advance from Takeda, which is reflected as a current liability in our December 31, ~~2012~~2013 financial statements. As a result of the recall, we also wrote off $8.4 million of inventory and prepayments made to our contract manufacturing organizations or CMOs. Given the uncertainty in future revenues at this time, we cannot predict if or when we will start recognizing revenues from API.

Impairment of Inventory and Losses on Firm Purchase Commitments

Impairment of inventory and losses on firm purchase commitments, as compared to prior years are as follows (in thousands):

	Year ended December 31,						Percent Change
	2012		2011		2010		2012/2011	2011/2010
	2013		2012		2011		2012/2011	2011/2010
Impairment of inventory and losses on firm purchase commitments	$	~~44,957~~—	$	—44,957	$	—	N/A	N/A

AsPrior ato ~~result of~~ the ~~voluntary recall of OMONTYS in February 2013~~Amendment, ~~any~~we ~~future~~initiated ~~collaboration~~orders ~~revenue~~for ~~related to~~ API iswith ~~significantly~~our ~~uncertain~~contract asmanufacturing ~~all~~organizations, ~~marketing~~or ~~activities~~CMOs ~~have~~based ~~been~~on ~~suspended~~forecasts ~~and~~from ~~there~~Takeda, iswhich ~~significant~~were ~~uncertainty~~based ason toexpected ~~when~~demand orfor ~~if we will be able to reintroduce~~ OMONTYS. ~~Dialysis~~ Orders ~~organizations~~generally have ~~been~~commenced ~~instructed~~once tothere ~~discontinue~~was ~~use~~a ~~and~~contractual ~~return~~commitment ~~any unused product to Takeda~~ for ~~a refund. If~~ the ~~recall~~API isfrom ~~not lifted and we are not able to reintroduce, this will result in a severe decrease to our profit equalization revenue or potentially profit equalization losses in future periods~~Takeda.

In As ~~connection~~a ~~with~~result of the ~~recall~~inability ~~and in consultation with Takeda, we have undertaken efforts~~ to ~~suspend~~sell ~~manufacturing~~OMONTYS ~~activities~~and to the ~~extent~~uncertainty ~~practicable pending consideration~~ of ~~next~~future ~~steps~~revenues, ~~with OMONTYS. If~~ we ~~are~~have ~~successful~~written indown ~~identifying~~our ~~the~~API ~~cause~~inventory ~~of these safety concerns~~ and ~~addressing~~prepayments ~~it,~~for weAPI ~~and~~being ~~Takeda~~produced ~~will~~by ~~determine~~our ~~the~~CMOs ~~next appropriate steps~~ to ~~take~~a ~~with~~net ~~OMONTYS. Prior~~realizable tovalue ~~such~~of ~~time,~~zero weand ~~plan~~have torecorded ~~evaluate~~a ~~strategies~~$10.4 tomillion ~~decrease~~impairment ~~our~~charge ~~ongoing~~related ~~manufacturing~~to ~~costs~~this ~~and~~writedown ~~commitments,~~during ~~including~~the ~~but~~year ~~not~~ended ~~limited~~December to31, ~~termination~~2012. We ofhave ~~orders~~also ~~and~~recorded ~~agreements,~~a ~~which~~$34.6 ~~may~~million ~~negatively~~loss ~~impact~~on ~~our~~firm ~~ability~~purchase tocommitments ~~reintroduce~~by ~~OMONTYS. If~~applying wethe ~~are~~same ~~able~~lower toof ~~reintroduce~~cost ~~OMONTYS,~~or wemarket ~~intend~~approach tothat ~~continue~~is toused ~~rely on third-party manufacturers~~ to ~~produce~~value ~~API,~~inventory ~~which~~during ~~may~~the ~~require~~same ~~significant effort and validation of new CMOs~~period.

WeCollaboration ~~initiate~~cost orders for API with our CMOs based on forecasts from Takeda, which are based on expected demand for OMONTYS. Orders generally have commenced once there was a contractual commitment for the API from Takeda. As of December 31, 2012, we have future purchase commitments amounting to $34.6 million covering CMO costs for API through 2013, assuming we continue manufacturing API according to plan. These future commitments are comprised of $5.8 million for firm purchase commitments of bulk poly(ethylene) glycol reagent, or PEG, and the remaining $28.8 million of manufacturing obligations relate to API, and are based on firm forecasts from Takeda and therefore may be subject to reimbursement under the API Supply Agreement with Takeda. If we elect to terminate one or more of our CMO contracts then the amount of the purchase commitment could be substantially reduced, and in lieu of termination, we may be able to negotiate a reduced obligation with our CMOs under existing agreements.

39Collaboration cost reimbursement as compared to the prior year are as follows (in thousands):



	Year ended December 31,					Percent Change
	2013	2012		2011		2013/2012	2012/2011
Collaboration cost reimbursement	$(43,451)	$	—	$	—	N/A	N/A

We recorded a benefit of $20.3 million in the quarter ended March 30, 2013, primarily related to the Takeda Q1 profit equalization payment, which represented recovery of amounts included in the $45.0 charge for impairment of inventory and loss on CMO purchase commitments in 2012. We had the right under the Arrangement to submit to Takeda for reimbursement for a portion of those charges. However because we had not presented such amounts to Takeda for reimbursement, and such reimbursements would be subject to Takeda's approval, we had not recorded a receivable for such amounts as of December 31, 2012.

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In ~~addition to~~ the ~~binding~~three ~~CMO~~months ~~purchase~~ended ~~commitments,~~June ~~we also had $10.4 million in inventory and prepayments made to our CMOs on our balance sheet as of December 31~~30, ~~2012. As a result of the the inability to sell OMONTYS and the uncertainty of future revenues~~2013, we ~~have~~settled ~~written down~~ our ~~API~~future ~~inventory~~purchase ~~and~~commitments ~~prepayments~~with ~~for API being produced by~~ our CMOs. We tooriginally recorded a ~~net~~CMO ~~realizable~~liability ~~value~~ of ~~zero and have recorded an~~ $1032.49 million ~~impairment~~comprised ~~charge~~of ~~related to this writedown. We have also recorded a~~ $345.64 million ~~loss~~for on firm purchase commitments ~~by applying the same lower~~ of ~~cost or market approach that is used to value inventory. If actual net realizable values of the underlying inventory are subsequently more favorable as a result of a reintroduction of the product~~PEG, ~~we may experience favorable effects on our operating results if any inventory impairment~~ and ~~losses on firm purchase commitments that have been recorded are reversed, potentially resulting in a gain. Of~~ the ~~total~~remaining $4527.05 million ~~charge for impairment~~ of ~~inventory~~manufacturing ~~and~~obligations ~~loss~~relate ~~on CMO purchase commitments, we have the right under the Arrangement~~ to ~~submit to Takeda for reimbursement $18~~API.~~4 million of such expenses.~~ ~~However~~We ~~because~~were ofable ~~uncertainty of future amounts~~ to besettle ~~received,~~these weobligations ~~have~~for ~~not recorded a receivable from Takeda~~$11. At0 ~~the~~million ~~time~~less wethan ~~and Takeda identify~~ the ~~cause~~contractual ~~of the safety concern~~amounts, ~~or if no cause is determined~~ and ~~both~~realized ~~parties~~favorable ~~agree~~adjustments ~~on an expense distribution, we would then expect~~ to ~~submit~~our ~~the~~operating ~~amounts~~results toof ~~Takeda~~$21.9 ~~for reimbursement~~million.

~~Takeda~~As ~~capitalizes~~a ~~inventory~~result ~~costs~~of ~~associated with~~ the ~~production~~Amendment, ofTakeda ~~OMONTYS~~assumed ~~and~~full ~~enters~~responsibility ~~into purchase commitments~~ for ~~goods~~OMONTYS, ~~associated~~including ~~with~~the ~~this~~ongoing ~~manufacturing. The~~recall ~~write~~and ~~down~~investigation ~~or write off~~ of ~~such~~OMONTYS ~~inventory~~as ~~and~~well as any ~~charges~~subsequent ~~for~~decisions ~~purchase~~as ~~commitments by Takeda would be subject~~ to ~~the~~whether ~~profit equalization revenue or loss calculation of~~ the ~~Arrangement. We~~product ~~estimate that inventory charges of $2.5 million~~ may be ~~billed~~subject to usreintroduction ~~during~~if ~~the first quarter of 2013 based on the manufacturing costs incrred by~~ Takeda as of December 31, 2012. With respect to purchase commitments, Takeda may request reimbursement for a portion of the costs associated with Takeda's firm purchase commitment of $9.3 million with Baxter for pre-filled syringes. Our exposure is ~~limited~~able to ~~the~~complete ~~portion of~~ the ~~Baxter~~investigation ~~agreement~~and ~~that~~address ~~relates to~~ the ~~U.S. We~~safety ~~have~~concerns ~~no liability related~~ to the ~~E.U.~~satisfaction ~~or Japan because in those countries we receive only a royalty on product sales and the collaboration profit split does not apply to operations in those countries. The amount~~ of ~~our exposure is estimated to be $0.7 million which we expect to incur in~~ the ~~first quarter of 2013~~FDA.

Per the Arrangement, the allocation of expenses incurred in connection with a recall is based on the source of the defect if determinable. We believe the total costs of recalling the product, which is primarily composed of costs to a third-party to gather, store, and return the product to Takeda, to be incurred in 2013, will range from $2.0 million to $3.0 million. The Arrangement provides that the allocation of expenses incurred in connection with a recall is to be based on the source of the defect, if determinable. If the recall is determined to be due to manufacturing defect of bulk API, then we are required to bear all such recall expenses. If the recall is determined to be due to manufacturing defect of finished product, then Takeda is required to bear all such recall expenses. If the recall is determined to be due to both manufacturing defects of the API and the manufacturing of the final drug product, then we and Takeda are required to share recall expenses proportionally. Given the ongoing nature of the investigation, the cause of the recall is not yet known and the range of recall costs that we may ultimately be responsible for may be up to the full amount of the costs incurred.

Research and Development Expenses

The major components of R&D expenses include clinical trial expenses, consulting and other third-party costs, API manufacturing costs incurred prior to FDA approval, salaries and employee benefits, license fees paid to third parties for use of their intellectual property, supplies and allocations of various overhead and occupancy costs. Clinical trial expenses include, but are not limited to, contract research organization, or CRO, and investigator fees, site costs, comparator drug costs and clinical research organization costs. All R&D expenses are expensed as incurred. R&D expenses, as compared to prior years are as follows (in thousands):

	Year ended December 31,						Percent Change
	2012		2011		2010		2012/2011		2011/2010
	2013		2012		2011		2013/2012		2012/2011
Research and development expenses	$	5111,~~738~~857	$	7651,~~308~~738	$	9376,~~638~~308	(3277	)%	(1932	)%

R&D expenses declined $39.9 million from 2012 to 2013. The reduction in R&D expenses in 2013 compared to 2012 was due to the recall of OMONTYS in February 2013. After the recall, we undertook a restructuring of the Company which involved the cessation of all R&D activity and a significant reduction in workforce including all R&D personnel.

R&D expenses declined $24.6 million from 2011 to 2012. The decrease in R&D expenses in 2012 compared to 2011 was primarily due to reduced consultant costs as a result of both the completion of our filing of our NDA in May 2011 and of the preparation for our FDA advisory committee meeting which occurred in December 2011 and reduced personnel related costs related to the reduction in force implemented in the third quarter of 2011. This was partially offset by ongoing clinical trial activity on our Phase 3b trial, and a Phase 2 study in Pure Red Cell Aplasia, or PRCA patients.

R&D expenses declined $17.3 million from 2010 to 2011. The decrease in R&D expenses in 2011 compared to 2010 was primarily due to reduced CRO and investigative site costs as a result of the completion of the treatment and follow up of our Phase 3 clinical trials in early 2010 as well as due to a $2.5 million reversal of R&D expense related to a change in estimate in

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our clinical trial accrual regarding final close-out activities with both of our major CROs on the Phase 3 studies. This decrease was partially offset by $8.0 million of fixed payments related to the settlement and license agreement, or the Settlement and License Agreement with Janssen Biotech, Inc. (a subsidiary of Johnson & Johnson) and certain of its affiliated companies, which we collectively refer to as Janssen (see Note 4 of Notes to Financial Statements), costs related to our Phase 3b study commenced in the third quarter of 2011 and $0.9 million in employee-related restructuring costs related to a reduction in force incurred in 2011.

We expect to critically evaluate the level of R&D expenses we incur in future periods as a result of the voluntary recall of OMONTYS in February 2013 and the uncertainty as to when or if we will be able to reintroduce OMONTYS. Except in connection with the investigation of the cause of the recall, we plan to suspend further investment in R&D, including conduct of clinical trials pending consideration of next steps with OMONTYS.

Selling, General and Administrative Expenses

SG&A expenses consist principally of salaries, employee benefits, consulting, professional fees for legal, auditing and tax services, marketing and commercial support for OMONTYS, allocation for overhead and occupancy costs and royalty expense. SG&A, expenses as compared to prior years are as follows (in thousands):

	Year ended December 31,						Percent Change
	2012		2011		2010		2012/2011		2011/2010
	2013		2012		2011		2013/2012		2012/2011
Selling, general and administrative expenses	$	8927,~~714~~529	$	3289,~~818~~714	$	3332,~~331~~818	~~173~~(69	)%	(2173	)%

SG&A expenses decreased $62.2 million from 2012 to 2013. The reduction in SG&A expenses in 2013 compared to 2012 was due to the recall of OMONTYS in February 2013. After the recall, we undertook a restructuring of the company which involved a significant reduction in workforce including all but four SG&A personnel.

SG&A expenses increased $56.9 million from 2011 to 2012. The increase in SG&A expenses in 2012 compared to 2011 was primarily due to higher commercialization expenses related to expansion of our commercial capabilities, including the establishment of a field sales force and other activities to support our commercialization efforts. In addition, as a result of our FDA approval, we also expensed a one-time milestone payment of $2.0 million to Nektar Therapeutics AL Corporation, or Nektar, during the three months ended March 31, 2012 and also incurred $1.8 million in royalty expense resulting from the introduction of OMONTYS in 2012.

~~SG&A~~As ~~expenses~~a ~~declined~~result ~~$0.5~~of ~~million~~the ~~from~~voluntary ~~2010~~recall toof ~~2011. The~~OMONTYS, ~~decrease~~all inproduct ~~SG&A expenses in 2011 as compared to 2010~~ was ~~primarily~~recalled ~~due~~and toall ~~lower~~marketing ~~legal~~activities ~~costs~~were suspended. ~~This~~As ~~decrease~~a ~~was~~result ~~partially offset by higher commercial expenses related to expansion~~ of ~~our~~the ~~commercial~~Amendment, ~~capabilities~~Takeda asassumed wefull ~~prepared~~responsibility for ~~potential FDA approval of~~ OMONTYS, aincluding ~~facilities-related~~the ~~restructuring~~ongoing ~~charge~~recall ~~of $0.9 million related to idle~~ and ~~excess~~investigation ~~office~~of ~~space, and increased employee compensation costs.~~

As a result of the voluntary recall of OMONTYS, all product has been recalled and all marketing activities have been suspended. There is significant uncertainty as to when or if we will be able to reintroduce OMONTYS. We are unlikely to be able to maintain the commercial and medical affairs resources and capabilities we had established prior to the recall, which would reduce our SG&A expenses; however this could negatively impact our ability to reintroduce OMONTYS even if we are able to successfully identify and address the cause of these safety concerns in the near term, which is highly uncertain.39

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OMONTYS as well as any subsequent decisions as to whether the product may be subject to reintroduction if Takeda is able to complete the investigation and address the safety concerns to the satisfaction of the FDA. We expect selling, general and administrative expenses for the foreseeable future to include a lower level of salaries, benefits, and professional fees to maintain the corporate administrative responsibilities.

Impairment (Gain on Disposal) of Prepaid Expenses, Fixed Assets and Intangible Assets

Impairment of prepaid expenses, fixed assets and intangible assets and percentage changes as compared to the prior year are as follows (in thousands):



	Year ended December 31,						Percent Change
	2013		2012		2011		2013/2012	2012/2011
Impairment (gain on disposal) of prepaid expenses, fixed assets and intangible assets	$	4,414	$	—	$	—	N/A	N/A

As a result of the product recall and related restructuring activities that occurred in the year ended December 31, 2013, we incurred impairment charges of $4.4 million. The impairment related to our prepaid expenses, fixed assets and our intangible assets related to our license with Janssen was $1.3 million, $1.9 million and $1.9 million, respectively. For the year ended December 31, 2013 we have realized a total gain upon the sale of property and equipment of $0.7 million.

Restructuring Charges

Restructuring charges and percentage changes as compared to the prior year are as follows (in thousands):



	Year ended December 31,						Percent Change
	2013		2012		2011		2013/2012	2012/2011
Restructuring charges	$	16,066	$	—	$	—	N/A	N/A

Beginning in March 2013, we undertook plans to reorganize our operations in order to reduce operating costs and focus on the OMONTYS safety and other related FDA issues associated with the recall of the product. By June 30, 2013, in addition to transitioning most activities to our collaborator, Takeda, we completed a reduction in force of most of our remaining employees, including all of our commercial and medical affairs field forces as well as other employees throughout the organization and we engaged an experienced restructuring firm, The Brenner Group. With the engagement of the restructuring firm, we terminated the employment of our former executive officers, including our Chief Executive Officer and Chief Financial Officer. We have incurred $16.1 million in restructuring charges related to the workforce reduction during the year ended December 31, 2013.

In June 2013 we moved our remaining four employees into new offices in Cupertino, California and vacated all of our previous office buildings in Palo Alto, California. In the quarter ended June 30, 2013, we recorded an expense of $2.5 million related to the termination of use of our previous office buildings. In August 2013 we signed an agreement with our landlord for the termination of the lease. The lease termination payment included forfeiture of our deposit of $50,000, release of a letter of credit for $1.1 million and cash payment of $1.4 million. Cash collateral for the letter of credit was held by our bank and shown as restricted cash on our balance sheet as of December 31 2012. This cash was used to fund release of the letter of credit in 2013.

Interest Income (Expense), Net

Interest income (expense), net as compared to prior years are as follows (in thousands):

	Year ended December 31,									Percent Change
	2012			2011			2010			2012/2011		2011/2010
	2013			2012			2011			2013/2012		2012/2011
Interest income	$	7721		$	~~169~~77		$	~~275~~169		(5473	)%	(3954	)%
Interest expense	$	(1,~~442~~565	)	$	(~~144~~1,442	)	$	(~~140~~144	)	~~901~~9	%	3901	%
Interest income (expense), net	$	(1,~~365~~544	)	$	25(1,365	)	$	~~135~~25		~~(5,560~~13	)%	(815,560	)%

The decrease from interest income, net to interest expense, net was due primarily to interest expense related to our notes payable with the Lenders and our launch allowance with Takeda and lower interest rates and lower average cash balance during the year ended December 31, 2012 compared to the same period in 2011. The decrease in interest income (expense), net in 2011 as compared to 2010 was due primarily to lower levels of cash, cash equivalents and investments earning interest, as well as due to generally lower interest rates during the year.40

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The ~~Since~~increase wein ~~suspended~~interest ~~the~~income ~~marketing~~(expense), ~~activities~~net ofduring ~~OMONTYS~~the ~~and~~year ~~voluntarily~~ended ~~recalled~~December ~~OMONTYS~~31, we2013 ~~may~~compared beto ~~in breach under our Loan Agreement. The voluntary recall may be considered a material adverse event under~~ the ~~Loan~~same ~~Agreement~~period ~~that may result~~ in an2012 ~~event~~was ofdue ~~default. If~~primarily ~~there~~to isfinal apayment ~~notice~~ of ~~default from the Lenders,~~ interest ~~expense~~and ~~may~~prepayment ~~increase~~fees inassociated ~~2013~~with ~~because of~~ the ~~acceleration~~discharge of ~~interest~~obligations ~~expense for interest payments due at maturity. Events of default~~ under ~~the~~our ~~Loan~~loan ~~Agreement~~agreement ~~provides~~with ~~the~~ Lenders ~~various rights~~, ~~including~~our ~~the~~launch ~~right~~allowance towith ~~require~~Takeda, ~~immediate~~lower ~~repayment of the outstanding principal plus accrued and unpaid~~ interest ~~through~~rates ~~the prepayment date, the final payment of $0.5 million~~ and ~~the~~lower ~~prepayment~~average ~~fee~~cash ~~of $0.5 million. Additionally, the default may increase the interest rate by an additional 500 basis points (5.0)% applied to the outstanding loan~~ balance.

The increase in interest income (expense), net during the year ended December 31, 2012 compared to the same period in 2011 was due primarily to interest expense related to our notes payable with the Lenders and our launch allowance with Takeda and lower interest rates and lower average cash balance.

Other Income (Expense), Net

Other income (expense), net as compared to prior years are as follows (in thousands):

	Year ended December 31,								Percent Change
	2012			2011			2010		2012/2011		2011/2010
	2013			2012			2011		2013/2012		2012/2011
Other income (expense), net	$	~~(34~~8	)	$	15(34	)	$	~~239~~15	(~~327~~124	)%	(94327	)%

Other expense, net, for the year ended December 31, ~~2012~~2013 includes a $3010,000 ~~loss~~of onunused ~~disposal~~flex ofspending ~~fixed~~account ~~assets~~funds. Other ~~income~~expense, net, for the year ended December 31, ~~2011~~2012 includes a $1330,000 ~~insurance~~loss ~~refund~~on disposal of fixed assets. Other income ~~(expense)~~, net, for ~~the~~ year ended December 31, ~~2010~~2011 ~~consists~~includes ~~primarily~~a of $~~244~~13,000 ~~from~~insurance ~~a qualified therapeutic discovery grant received from the U~~refund.~~S. government.~~

Provision for Income Taxes

We are subject to federal and state income taxes. While we did generate net income during the ~~first~~ second quarter of ~~2012~~2013 due to ~~significant~~adjustment ~~milestone~~of ~~payments~~charges ~~received~~for the impairment of inventory and purchase commitments in the period, resulting in a gain during the second quarter, we were in a net operating loss position for ~~2012~~the year 2013 and therefore have not recorded any federal or state taxes, other than a$2.2 million tax benefit, which was recorded in the second quarter of ~~federal~~2013 as a result of statute of limitations lapsing on a previously ~~reserved~~recorded uncertain tax ~~benefit~~ position, and the minimum statutory California tax, for the year ended December 31, ~~2012~~2013. We also did not record any tax liability for the year ended December 31, ~~2011~~2012 and ~~2010~~2011 other than the minimum statutory California tax due to the anticipated tax loss position for the year ended December 31, ~~2011~~2012 and ~~2010~~2011.

~~As of December 31, 2012 and 2011, we have a net deferred tax asset balance of $7~~.2 million each, in consideration of the uncertainty in income taxes liability recorded for the same amount. We have incurred significant operating losses since inception and anticipate that we may incur continued losses in the future.

As of December 31, 2012, we had a net deferred tax asset balance of $7.2 million in consideration of the uncertainty in income taxes liability recorded for the same amount. In 2013, the Company adopted Accounting Standards Update No. 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists. This standard resulted in the offset of the deferred tax asset with the uncertain tax position on the balance sheet such that there are no deferred tax assets or liabilities presented on the balance sheet as of December 31, 2013. We have incurred significant operating losses since inception and anticipate that we may incur continued losses in the future.

Liquidity and Capital Resources

Our cash, cash equivalents, and investments at December 31, ~~2012~~2013 and ~~2011~~2012 are as follows (in thousands):

	December 31,
	2012	2011
	2013		2012
Cash and cash equivalents	$685,~~265~~597	~~$54,339~~	$68,265
Short-term investments	~~$9,717~~—	~~$44,165~~	9,717
Long-term investments	~~$2,323~~—	—	2,323

As of December 31, ~~2012~~2013, we had $815.46 million in cash, ~~cash equivalents, restricted cash~~ and ~~marketable securities. Our~~ cash ~~and investment balances are held in a variety of interest bearing instruments, including corporate debt securities, and money market funds~~equivalents. ~~Cash in excess of immediate requirements is invested in accordance with our investment policy primarily with a view to liquidity and capital preservation. As of December 31~~, ~~2012, we had total debt of $8.8 million, which consists of the face value of the notes payable less the net debt discount associated with the issuance of warrants to our Lenders.~~

Working Capital. Working capital (deficit) was $3(2.46) million at December 31, ~~2012~~2013, a decrease of $836.90 million from working capital as of December 31, ~~2011~~2012. ~~This~~The ~~decrease~~change in working capital was primarily attributable to:

~~• a decline of $20.5 million in cash, cash equivalents and marketable securities~~41

• an increase of $38.5 million in accrued liabilities, primarily related to accrued potential losses on firm purchase commitments

• an increase of $27.7 million in Advance from Takeda

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•a andecline ~~increase~~ of $872.84 million in ~~the~~cash, ~~current~~cash ~~portion~~equivalents ofand ~~debt.~~marketable securities

•a ~~The~~ decrease ~~was~~of ~~partially~~$51.9 ~~offset~~million byin anaccrued ~~increase~~liabilities, ofprimarily ~~$11.4~~related ~~million~~to accrued potential losses on firm purchase commitments in ~~accounts~~2012 ~~receivable~~which ~~from~~were ~~Takeda.~~settled in 2013

As •a ~~result~~decrease of the February 23, 2013 nationwide voluntary recall of OMONTYS and the suspension of all marketing activities, there is significant uncertainty as to whether we will have sufficient existing cash, cash equivalents and investments to fund our operations for the next 12 months$19. If5 wemillion were to reduce cash outflows, there is no assurance that we will be able to reduce our operating expenses enough to meet our existing obligations. If we are not able to reintroduce the product or obtain additional funding in ~~the~~Advance ~~near~~from future, our cash resources will rapidly be depleted and we will be required to materially reduce or suspend operations, which would likely have a material adverse effect on our business, stock price and our relationships with third parties with whom we have business relationships, at least until additional funding is obtained. If we do not have sufficient funds to continue operations, we could be required to liquidate our assets, including relinquish some or all of our existing rights to OMONTYS, seek bankruptcy protection or other alternatives that would likely result in receiving less than the value at which those assets are carried on our financial statements, and it is likely that investors will lose all or some of their investment in us. Any failure to dispel any continuing doubts about our ability to continue as a going concern could adversely affect our ability to enter into collaborative relationships with business partners, make it more difficult to obtain required financing on favorable terms or at all, negatively affect the market price of our common stock and could otherwise have a material adverse effect on our business, financial condition and results of operations.Takeda

In March 2013, we undertook plans to reorganize our operations in order to reduce operating costs and focus on the OMONTYS safety and other related FDA issues associated with the recall of the product. In addition to transitioning many of the ongoing activities to our collaborator, Takeda, our plans include •a ~~significant~~decrease ~~reduction in force~~ of ~~approximately 230 employees (75% of our workforce), including our commercial and medical affairs field forces as well as other employees throughout the organization. We expect to incur between~~ $8.08 million ~~and $10.0 million~~ in ~~restructuring charges related to~~ the ~~workforce~~current ~~reduction~~portion ~~during the first quarter~~ of ~~2013~~debt. As a result of this restructuring and the recall, we may also incur additional charges depending on further review and additional reductions in operations and may also experience impairment changes with respect to our property and equipment and long lived assets in the first quarter of 2013.

We•a ~~will~~decrease ~~continue to review our operations as we discuss with Takeda the roles and responsibilities~~ of ~~the parties in addressing our regulatory and other obligations resulting from the OMONTYS recall~~$18. In4 ~~any~~million ~~event, we plan to continue to make efforts to substantially reduce our operating costs, which will likely include further reductions~~ in ~~force~~accounts asreceivable ~~we endeavor to conserve our cash resources. We have been in discussions with, and are planning to seek further assistance and support~~ from Takeda ~~as we transition from a commercial operating company to a company potentially without any product~~. We are undertaking steps to reduce all of our outstanding obligations to third parties and are dependent on those efforts to continue operations even in the near term, however, we may not be successful. We are particularly dependent on Takeda's willingness to continue the collaboration in a modified form that reduces our operating expenses and responsibilities under the collaboration, but we may also be required to reduce our share of OMONTYS profits if and when the product may be re-introduced in the future. Even if Takeda is willing to assume additional responsibilities under the collaboration, including the conduct of most or all of the ongoing investigation, the loss of critical personnel and functions means that we may not be able to maintain our operations, support the NDA, continue as a going concern or ever re-introduce OMONTYS.

InWe ~~view~~believe we have sufficient cash to fund our operations through the third quarter of 2014. However, there is significant uncertainty as to whether we will have sufficient existing cash to fund our operations beyond the third quarter of 2014. Our liabilities exceed our assets. Given our limited resources, ~~and~~there ~~funds,~~is no assurance that we ~~plan~~will be able to ~~explore~~reduce ~~various~~our ~~strategic~~operating ~~alternatives,~~expenses ~~including~~enough ato ~~sale~~meet ofour existing and future obligations. If Takeda is not able to reintroduce the ~~company~~product or ~~its~~we ~~assets~~are not able to obtain additional funding in the near future, our cash resources will rapidly be depleted and we will be required to materially reduce or suspend operations, which would likely have a ~~corporate~~material ~~merger~~adverse effect on our business, stock price and our relationships with third parties with whom we have business relationships. We If ~~are~~we ~~considering~~do ~~all~~not ~~possible~~have ~~alternatives~~sufficient funds to continue operations, we could be required to liquidate our assets, including ~~further~~relinquish ~~restructuring~~some ~~activities~~or all of our existing rights to OMONTYS, ~~wind-down~~seek bankruptcy protection or other alternatives and it is likely that investors will lose all or some of ~~operations~~their investment in us. Any failure to dispel any continuing doubts about our ability to continue as a going concern could make it more difficult to obtain required financing on favorable terms or ~~even~~at ~~bankruptcy~~all, ~~proceedings~~negatively affect the market price of our common stock and could otherwise have a material adverse effect on our business, financial condition and results of operations.

IfOur ~~the~~independent ~~recall~~registered ispublic ~~not~~accounting ~~lifted and we are not able to reintroduce OMONTYS~~firm, ~~this will result~~ in atheir ~~severe~~most decrease to our profit equalization revenue in future periods. Even if we are successful in reintroducing and commercializing OMONTYS in the future, there can be no assurance that revenues will ramp up rapidly enough to offset operating losses and repayment of debts. Further challenges or delays to potential reintroduction and commercialization of OMONTYS may require us to raise additional funding to successfully reintroduce and commercialize OMONTYS. We may seek to raise additional funds through public or private financing, strategic partnerships or other arrangements. Any additional equity financing would be dilutive to stockholders and debt financing, if available, may involve restrictive covenants that may limit our ability to conduct our business and increase our risk of defaults. The market may take into consideration of the recent ~~recall~~audit ~~of OMONTYS~~report, ~~which~~expressed ~~recall~~substantial isdoubt ~~described under~~about ~~the caption “OMONTYS Voluntary Recall” in “Item 1. Business” of this Annual Report on Form 10-K which may negatively affect~~ our ability to ~~obtain~~continue ~~additional~~as ~~funding. Market~~a ~~conditions~~going may significantly limit our ability to raise funds such that there can be no assurance we can raise the additional funds to support our continuing operations, and successfully reintroduce and commercialize OMONTYS, and funding may not be available to us on acceptable terms, or at allconcern. ~~Since~~ we suspended the marketing activities of OMONTYS and voluntarily recalled OMONTYS, we may be in breach under our Loan Agreement with the Lenders. The voluntary recall may be considered a material adverse event under the Loan

43Cash Flows during the Years Ended December 31, 2013, 2012, and 2011

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Agreement which may result in an event of default. Therefore, the remaining $20.0 million under the Loan Agreement may no be longer available to us.

Our independent registered public accounting firm, in their audit report on our financial statements for the year ended December 31, 2012, expressed substantial doubt about our ability to continue as a going concern.

Since our inception, we have financed our operations through sale of capital stock, license fees, milestone payments, reimbursement for development and commercial expenses, profit equalization revenue for OMONTYS, and manufacturing costs from collaborative partners, issuance of notes payable, capital lease financing, interest earned on investments and limited license fees and royalties from licensing intellectual property. From inception through December 31, 2012, we have received net proceeds of $458.5 million from the issuance of equity securities, including $53.6 million in net proceeds from the sale of 9,745,762 shares of our common stock in a secondary public offering in March 2011.

Due to our announcement of our voluntary recall of OMONTYS in February 2013, there has been an extremely high volume of trading of our stock, which has caused a significant drop in the value of our stock. As a result of the high trading volume, there may be a shift of ownership amongst our 5% stockholders that could result in an ownership change, under Section 382 of the Internal Revenue Code of 1986, as amended. Under Section 382, a corporation that undergoes an ownership change, as defined by the Internal Revenue Code, may be subject to significant limitations on its ability to utilize its net operating losses or NOLs, and tax credits accumulated prior to the ownership change to offset future taxable income or tax liabilities. We are currently in the process of assessing the impact. At December 31, 2012, deferred tax assets were offset by a valuation allowance except to the extent of possible taxable income in an earlier period.

Financing Agreements

Loan Agreement. In March 2012, we entered into the Loan Agreement, with the Lenders, under which we may borrow up to a total of $30.0 million in two tranches for general corporate purposes. The first tranche of $10.0 million was borrowed in March 2012. The second tranche of $20.0 million was available for drawdown until March 31, 2013; however, it may no longer be available due to our recent recall of OMONTYS. Events of default include failure to deliver financial statements and reports to the Lenders on a timely basis, failure to file all required tax returns on a timely basis, failure to maintain insurance on collateral, and other routine and customary requirements under a loan agreement. The Loan Agreement also contains negative covenants that restrict our ability to incur additional debt financing, change in business purpose, merge or consolidate, or encumbrance of assets without prior written consent of the Lenders. The interest rate for the first tranche will be fixed upon drawdown of the respective tranche at a per annum rate equal to the greater of 8.95% or 8.57% plus the then effective U.S. Treasury note yield to maturity for a 36 month term determined three (3) business days prior to the funding date of the tranche (but in any event not less than thirty-eight basis points (0.38%)). The interest rate related to the drawdown of the first tranche is 9.11%. Payments under the Loan Agreement for the first tranche are interest-only through February 1, 2013, followed by equal monthly payments of principal and interest through the scheduled maturity date on July 1, 2015. In addition to the monthly principal and interest payments, a final payment equal to 5% of the aggregate amount drawn, or $0.5 million for the first tranche, will be due on the earliest to occur of (1) the last amortized payment, (2) the acceleration of the loan or (3) prepayments of the loan, as specified in the Loan Agreement (See Note 8 of Notes to Financial Statements). Since we suspended the marketing activities of OMONTYS and voluntarily recalled OMONTYS, we may be in breach under our Loan Agreement. The voluntary recall may be considered a material adverse event under the Loan Agreement which may result in an event of default. Events of default under the Loan Agreement provide the Lenders with various rights, including the right to require immediate repayment of the outstanding principal plus accrued and unpaid interest through the prepayment date, the final payment of $0.5 million and the prepayment fee of $0.5 million. We have not received a notice of default. If we receive a notice of default from the Lenders, in addition to repaying the outstanding balance of our loan, we will also accrue the remaining final interest charge and the full amount of the final payment and the prepayment fee.

Funding from our Collaboration Partner

We have received cumulative amounts of $122.0 million of upfront license fees, $115.3 million in milestone payments and $297.2 million related to profit equalization revenue, the reimbursement of development and commercialization expenses and purchase of API under our Arrangement with Takeda. Takeda has the right to terminate the June 2006 collaboration agreement in its entirety, upon written notice to Affymax by at least six months written notice prior to the effective date of the termination.

In early 2013 and in consultation with the FDA, we and Takeda voluntarily recalled OMONTYS nationwide from the market as a result of post-marketing reports regarding safety concerns, including anaphylaxis, which can be life-threatening or fatal. In connection with the recall, we and Takeda suspended all promotional and marketing activities for OMONTYS. While we continue to investigate the potential cause of the safety concerns, we are unable to estimate the scope or timelines associated

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with the investigation. If we are unable to identify and rectify the causes of the safety concerns to the satisfaction of the FDA, OMONTYS may be withdrawn from the market and we may be unable to continue our operations as a going concern.

Eligible Profit Equalization Profit and Loss from our Collaboration Partner.

In connection with the recall and in consultation with Takeda, as appropriate, we plan to evaluate the near-term activities, our respective rights and obligations of the parties under the agreements including the deployment of resources as part of our efforts to decrease our ongoing costs and commitments, which may negatively impact our ability to reintroduce OMONTYS, if such opportunity arises.

Takeda capitalizes inventory costs associated with the production of OMONTYS and enters into purchase commitments for goods associated with this manufacturing. The write down or write off of such inventory and any charges for purchase commitments by Takeda would be subject to the profit equalization revenue or loss calculation of the Arrangement. We estimate that inventory charges of $2.5 million may be billed to us during the first quarter of 2013 based on the manufacturing costs incurred by Takeda as of December 31, 2012. With respect to purchase commitments, Takeda may request reimbursement for a portion of the costs associated with Takeda's firm purchase commitment of $9.3 million with Baxter for pre-filled syringes. Our exposure is limited to the portion of the Baxter agreement that relates to the U.S. We have no liability related to the E.U. or Japan because in those countries we receive only a royalty on product sales and the collaboration profit split does not apply to operations in those countries. The amount of our exposure is estimated to be $0.7 million which we expect to incur in the first quarter of 2013.

We believe the total costs of recalling the product, which is primarily composed of costs to a third-party to gather, store, and return the product to Takeda will range from $2.0 million to $3.0 million. These costs are expected to be primarily incurred in the first quarter of 2013 and have not been accrued as of December 31, 2012. The Arrangement provides that the allocation of expenses incurred in connection with a recall is to be based on the source of the defect, if determinable. If the recall is determined to be due to manufacturing defect of bulk API, then we are required to bear all such recall expenses. If the recall is determined to be due to manufacturing defect of finished product, then Takeda is required to bear all such recall expenses. If the recall is determined to be due to both manufacturing defects of the API and the manufacturing of the final drug product, then we and Takeda are required to share recall expenses proportionally. Given the ongoing nature of the investigation, the cause of the recall is not yet known and the range of recall costs that we may ultimately be responsible for may be up to the full amount of the costs incurred.

In the first quarter of 2013, we believe Takeda will record an impairment charge for certain long lived assets associated with OMONTYS. Under the profit/loss equalization, we are responsible for half of these charges. We estimate our exposure related to this impairment to be approximately $7.0 million. This amount has not been accrued as of December 31, 2012.

Profit Equalization Revenue/Loss. While Takeda is responsible for the sale of OMONTYS and accordingly Takeda records product revenue, we and Takeda share equally in the net profits and losses of OMONTYS in the U.S. The profit equalization revenue is calculated on a quarterly basis as the amount required so that the profit or loss realized by both Affymax and Takeda on the product equates to 50% of the total product profit or loss. In determining the OMONTYS net profit or loss, OMONTYS product revenue is reduced by rebates and discounts, cost of goods, and other gross-to-net adjustments incurred by Takeda; royalty expense incurred by us, commercialization expenses (FTE related and out of pocket costs) incurred by both Takeda and us, and certain development costs associated with post-marketing development activities (FTE related and out of pocket costs) incurred by Takeda and us. The profit equalization amount is recognized as revenue in the period the product sales occur and product revenue is recognized by Takeda.

Launch Allowance. Takeda funded the first $20.0 million of U.S. commercial expenses. Amounts received under the launch allowance are non-refundable. As part of the launch allowance, Takeda is entitled to deduct up to 8% of net sales from the profit share amounts which would have otherwise been due to us each period until they have recouped an amount equal to $11.0 million (see Note 3 of Notes to Financial Statements). In 2012, Takeda deducted a total of $2.8 million against the profit equalization and are eligible to deduct the balance against future profit equalization revenue.

API Payments. Under the terms of the API Supply Agreement, we are responsible for the manufacture and supply of all quantities of API to be used in the development and commercialization of OMONTYS worldwide. Takeda reimburses us for our cost of API plus 20%. During the year ended December 31, 2012, we received $13.5 million in payments for API, substantially all of which is recorded as a liability in our balance sheet as an Advance from Takeda as of December 31, 2012.

Milestone Payments. Additionally, we are eligible to receive a total of $357.0 million in additional milestone payments, which include the milestones below. Upon the successful achievement of as yet unmet clinical development and regulatory milestones, we are eligible to receive from Takeda an additional aggregate amount of $95.0 million of substantive milestone payments relating to the renal program of which $20.0 million is associated with the first approval in either pre-dialysis or

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dialysis indication in the first major European Union or E.U. country. The remaining $75.0 million in payments for the renal program under the worldwide agreement are aggregated as they do not have estimated dates of achievement in the near- or medium-term. In addition, we are eligible to receive from Takeda an aggregate of $112.0 million of substantive milestone payments related to oncology for unmet clinical development and regulatory milestones and only a portion of these payments relate to the U.S. The collaboration is not pursuing the oncology program; accordingly, future payment of this aggregate amount is unlikely. In addition, we are eligible to receive up to $150.0 million of sales-based milestones. Although we are eligible to receive future milestones from Takeda, timing and amounts of future milestone payments, if any, are extremely uncertain due to the recall.

Expense Reimbursement Payments. We are eligible to receive reimbursement from Takeda for 70% of all third-party expenses related to U.S. development in the U.S. (See Note 3 of Notes to Financial Statements).

Settlement and License Agreement

In November 2011, we entered into the Settlement and License Agreement with Janssen, which required us to make two fixed payments to Janssen of $6.0 million, which was paid in December 2011, and $2.0 million which was paid in June 2012. The Settlement and License Agreement required us to make a $2.5 million milestone payment to Janssen upon FDA regulatory approval of OMONTYS, and requires us to make a $2.5 million milestone payment to Janssen upon regulatory approval of OMONTYS in the first major European country. In addition, Janssen will be entitled to royalties on sales of OMONTYS in Europe, Japan and certain other countries outside of the U.S. until mid-2016. Upon execution of the Settlement and License Agreement in the fourth quarter of 2011, we recorded $8.0 million of R&D expense relating to the fixed payments. Upon FDA approval of OMONTYS in March 2012, we capitalized $2.5 million related to the first milestone payment during the first quarter of 2012. The resulting asset will be amortized over the expected life of the related patent family, the last-expiring patent of which expires in June 2016. This $2.5 million milestone payment to Janssen was paid in April 2012.

Concurrent with the execution of the Settlement and License Agreement, we and Takeda entered into an amendment to the Arrangement. Under the terms of this amendment, Takeda agreed to pay up to $6.5 million in additional milestones to us in consideration of the upfront and milestone payments that we are required to make to Janssen under the Settlement and License Agreement (see Note 4 of Notes to Financial Statements). These milestones were substantive and at risk at the time that we entered into the amendment with Takeda. $5.25 million of these milestones are earned based on regulatory and commercial events in the U.S. and the remaining $1.25 million is tied to regulatory events in the E.U. As of June 30, 2012, $3.0 million of these milestones had been earned as a result of FDA approval of OMONTYS, which we received payment in the second quarter of 2012. In July 2012, we earned an additional $2.25 million milestone as a result of commercial progress on the OMONTYS product launch, which was recognized as revenue in the third quarter of 2012. There are no royalties to Janssen on U.S. sales of OMONTYS, but we are solely responsible for the royalty payment to Janssen on sales of OMONTYS in certain regions outside the U.S. when and if it is approved in those regions.

Cash Flows during the Years Ended December 31, 2012, 2011, and 2010

In summary, our cash flows for the periods presented are as follows (in thousands):

	December 31,
	2012			2011			2010
	2013			2012			2011
Net cash used in operating activities	$	(3767,~~180~~339	)	$	(7137,~~966~~180	)	$	(4971,~~234~~966	)
Net cash provided by (used in) investing activities	2714,~~995~~400			827,~~001~~995			~~(11~~8,~~479~~001		)
Net cash provided by (used in) financing activities	23(9,~~111~~729		)	5423,~~805~~111			(154,~~084~~805		)

Net cash used in operating activities for the years ended December 31, ~~2012~~2013, ~~2011~~2012, and ~~2010~~2011, was $3767.23 million, $7237.02 million, and $4972.20 million, respectively. Net cash used in operations for all periods reflects our net loss partially offset by the benefit of payments received from Takeda related to milestone payments, ~~profit~~non-cash ~~equalization~~expenses ~~revenue,~~related ~~and~~to ~~reimbursement~~impairment ~~for~~of ~~development~~inventory and ~~commercial~~losses ~~expense~~on firm purchase commitments and ~~purchases~~reimbursement offor ~~API~~development byand ~~Takeda~~commercial expense. Cash used in operating activities in ~~2012~~2013 as compared to ~~2011~~2012 ~~decreased~~increased by $3430.82 million primarily due to higher ~~noncash~~non-cash expenses related to impairment of inventory and losses on firm purchase commitments and a reduction in ~~2012~~accrued liabilities and accounts payable in 2013 compared to ~~2011~~2012. Cash used in operating activities in ~~2011~~2012 as compared to ~~2010~~2011 ~~increased~~decreased by $2234.78 million primarily due to a higher ~~net~~noncash ~~loss~~expenses related to impairment of inventory and losses on firm purchase commitments that occurred in ~~2011~~2012 compared to ~~2010~~2011.

Net cash provided by investing activities for the year ended December 31, 2013 of $14.4 million was primarily due to maturities of investments, sale of securities, proceeds from the sale of property and equipment and change in restricted cash. Net cash provided by investing activities for the year ended December 31, 2012 of $28.0 million was primarily due to maturities of investments, partially offset by the purchases of investments and property and equipment and payments related to OMONTYS intellectual property. Net cash provided by investing activities for the year ended December 31, 2011 of $8.0 million was primarily a result of purchases of investments partially offset by proceeds from maturities and sales of investments.

46Net cash used in financing activities for the year ended December 31, 2013 was primarily attributable to repayment of notes payable of $10.0 million. In March 2012, we entered into the Loan Agreement, with the Lenders, under which we borrowed $10.0 million. On April 3, 2013, we entered into a Letter Agreement, relating to the Loan Agreement dated March 26, 2012, with the Lenders. Pursuant to the terms of the Letter Agreement: (i) we paid all amounts due and owing so

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as to discharge our obligations thereunder totaling $9.8 million ~~was~~including ~~primarily~~remaining aprincipal, ~~result~~interest, offinal ~~proceeds~~payment ~~from~~and ~~maturities~~prepayment offees, ~~investments~~(ii) ~~offset~~we bywaived ~~purchases~~any ofrights ~~investments. Net~~to ~~cash~~seek ~~used~~additional incredit ~~investing~~extensions ~~activities~~or ~~for~~unfunded ~~the~~commitments ~~year~~under ~~ended~~the ~~December 31~~Loan Agreement, ~~2010~~and of(iii) ~~$11.5~~the ~~million~~security ~~was~~interest ~~primarily~~granted ato ~~result~~Lenders ofrelating ~~purchases~~to substantially all of ~~investments~~our ~~partially~~assets, ~~offset~~other bythan ~~proceeds~~our ~~from~~intellectual ~~maturities~~property, ~~and~~was ~~sales~~terminated. As of ~~investments~~December 31, 2013, we have no amounts outstanding or owing on the Loan Agreement.

Net cash provided by financing activities for the year ended December 31, 2012 was primarily attributable to proceeds of $10.0 million received from the issuance of a notes payable and $13.1 million received from the issuance of common stock upon exercise of stock options and our employee stock purchase plan. Net cash provided by financing activities for the year ended December 31, 2011 was primarily attributable to net proceeds of $53.6 million received from our secondary public offering in March 2011 and proceeds received from the issuance of common stock upon exercise of stock options. Net cash used in financing activities for the year ended December 31, 2010 was primarily attributable to the $9.2 million repayment of a loan from UBS Financial Services related to investments for which there was no market during the year, partially offset by $4.9 million in net proceeds from a financing executed under our equity line of credit with Azimuth Opportunity, Ltd. during the year.

In early 2013 and in consultation with the FDA, we and Takeda, voluntarily recalled OMONTYS nationwide from the market as a result of post-marketing reports regarding safety concerns, including anaphylaxis, which can be life-threatening or fatal. In connection with the recall, we and Takeda suspended all promotional and marketing activities for OMONTYS. While we continue to investigate the potential cause of the safety concerns, we are unable to estimate the scope or timelines associated with the investigation. If we are unable to identify and rectify the causes of the safety concerns to the satisfaction of the FDA, OMONTYS may be withdrawn from the market and we may be unable to continue our operations as a going concern.

Contractual Obligations and Significant Commitments

Our future contractual obligations, including financing costs, at December 31, ~~2012~~2013, are as follows (in thousands):

	Payments Due by Period
Contractual Obligations	Total		~~2013~~2014		~~2014~~2015 - ~~2015~~2016		~~2016~~2017 -~~2017~~2018		Thereafter
Operating lease obligations (1)	$	7,495	$	4,229	$	3,266	$	—	$	—
Operating lease obligations	$	23	$	23	$	—	$	—	$	—
Notes payable (2)	10,000		3,730		6,270		—		—
Total fixed contractual obligations	$	23	$	23	$	—	$	—	$	—
Interest payments on notes payable, fixed rate (2)	1,719		758		961		—		—
Manufacturing obligations (3)	34,599		34,004		595
Total fixed contractual obligations (4)	$	53,813	$	42,721	$	11,092	$	—	$	—

~~________________________________~~In addition the amounts reflected in the table above, we have recognized as a liability on our balance sheet an Advance from Takeda of $8.2 million which may be contingently offset against future royalties that may be due to us from Takeda. Takeda funded the first $20.0 million of U.S. commercial expenses. Amounts received under the launch allowance are non-refundable. As part of the launch allowance, Takeda is entitled to deduct up to 8% of net sales from the profit share amounts which would have otherwise been due to us each period until they have recouped an amount equal to $11.0 million (see Note 3 of Notes to Financial Statements). To date, Takeda deducted a total of $2.8 million against the profit equalization. Future royalties, if any, may be offset against the launch allowance of $8.2 million which is classified as Advance from Takeda in the balance sheet

(1) Relates primarily to minimum lease payments for lease of our facilities, consisting of approximately 113,000 square feet which expire in September 2014.

(2) Relates to Loan Agreement with the Lenders which includes interest due on the loan and $0.5 million related to the final payment. If we receive a notice of default from the Lenders, we will be obligated to pay the remaining final interest charge and the prepayment fee of $0.5 million.

(3) Relates to significant non-cancelable orders and minimum commitments under our agreements with CMOs relating to the manufacturing of OMONTYS API.

(4) These fixed contractual obligations do not include the Advance from Takeda that may have to be refunded to Takeda.

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In April 2004, we entered into a License, Manufacturing and Supply Agreement with Nektar under which we obtained from Nektar a worldwide, non-exclusive license, with limited rights to grant sublicenses, to certain intellectual property covering pegylation technology to manufacture, develop and commercialize OMONTYS. In consideration of the license grant, we agreed to pay royalties on the sales of OMONTYS. We also agreed to pay base milestones plus possible additional milestones in connection with our partnering activities relating to OMONTYS or merger and acquisition activities. As of December 31, 2012, no further milestone obligations remain.

Under the agreement, we also engaged Nektar for the manufacture and supply of our requirements of bulk PEG for the manufacture of OMONTYS. This relationship is managed by a managing committee formed by representatives from both us and Nektar. Nektar is obligated to engage a third party manufacturer in the event of Nektar's failure (as defined in the agreement) to supply PEG. This agreement expires, on a country by country basis, upon the expiration of our royalty payment obligations. The agreement may be terminated by either party for the other party's material breach provided that such other party has been given a chance to cure such breach, or by Nektar for our challenge of the validity or enforceability of any patents licensed thereunder.

Going Concern

Our financial statements have been presented on the basis that we continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. The lack of financial resources due to the recall of OMONTYS raises substantial doubt about our ability to continue as a going concern. The financial statements do not include any adjustments that might be necessary if we are unable to continue as a going concern.

Off-Balance Sheet Arrangements

At December 31, ~~2012~~2013, we did not have any off-balance sheet arrangements, as defined in Item 303(a)(4)(ii) of Regulation S-K promulgated by the Securities and Exchange Commission, or SEC, that have or are reasonably likely to have a current or future effect on our financial condition, changes in our financial condition, revenues, or expenses, results of operations, liquidity, capital expenditures, or capital resources that is material to investors.

Critical Accounting Policies and Significant Judgments and Estimates

Our management’s discussion and analysis of our financial condition and results of operations is based on our financial statements, which have been prepared in accordance with U.S. generally accepted accounting principles, or GAAP. The preparation of these financial statements requires us to make estimates, assumptions and judgments that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported revenues and expenses during the reporting periods. On an ongoing basis, we evaluate our estimates and judgments related to impairment of long-lived assets, restructuring charges, revenue recognition and clinical development costs. We base our estimates on historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. We believe the following policies to be the most critical to an understanding of our financial condition and results of operations because they require us to make estimates, assumptions and judgments about matters that are inherently uncertain.

~~Product~~Our ~~Recall~~critical accounting policies and the use of estimates are summarized below:

On February 23, 2013, we and Takeda announced a nationwide voluntary recall of OMONTYS as a result of postmarketing reports regarding safety concerns, including anaphylaxis, which can be life-threatening or fatal. We have evaluated this subsequent event to determine the accounting impacts of this particular event and related effects on our financial statements as of December 31, 2012. Based on our analysis that is ongoing, we have not discovered any indication that a condition existed as of December 31, 2012 and we believe that this event relates to conditions that did not exist as of December 31, 2012. Given the nature and significance of this event, we have provided additional disclosure as appropriate. We also reviewed account balances subject to estimation at December 31, 2012, including inventory and inventory purchase commitment obligations, for which we perform a lower of cost or market analysis, to determine if those account balances should be updated based on revised estimates with information available prior to the date the financial statements were issued. As of the result of the recall, we recorded financial statement adjustments to reflect changes in our estimates through the filing date of our Annual Report on Form 10-K as to the recoverability of inventory and deposits made to our CMOs, loss on firm purchase commitments and changes in the short term and long-term classification of certain liabilities. See Notes 1, 2, 3, 5, and 8 of the Notes to the Financial Statements. 43

Revenue Recognition

Collaboration Revenue

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We recognize revenue for contracts entered into prior to 2011 in accordance with the SEC, Staff Bulletin No. 101, Revenue Recognition in Financial Statements, as amended by Staff Accounting Bulletin or SAB, No. 104, Revision of Topic 13 and Accounting Standards Codification, or ASC, 605-25, Multiple Element Arrangements. When evaluating multiple element arrangements, we consider whether the components of the arrangement represent separate units of accounting as defined in the authoritative guidance for revenue arrangements with multiple deliverables. Application of this guidance requires subjective determinations and requires management to make judgments about the fair value of the individual elements and whether such elements are separable from the other aspects of the contractual relationship. We continue to follow the guidance of ASC 605-25 to determine whether the components of the Arrangement represent separate units of accounting. To determine if a delivered item can be treated as a separate unit of accounting, we evaluate (1) if the delivered item(s) has value to Takeda on a standalone basis; (2) there is objective and reliable evidence of fair value of the undelivered item(s) and (3) if a general right of return exists for the delivered item (e.g. contingencies), delivery or performance of the undelivered item(s) is considered probable and is substantially within the control of the company. We recognize revenue for contracts entered into or modified after January 1, 2011, in accordance with Accounting Standards Update, or ASU, No. 2009-13, Multiple Deliverable Revenue Arrangements. This update amends the guidance on accounting for arrangements with multiple deliverables to require that each deliverable be evaluated to determine whether it qualifies as a separate unit of accounting. This determination is generally based on whether the deliverable has stand-alone value to the customer. This update also establishes a selling price hierarchy for determining how to allocate arrangement consideration to identified units of accounting. The selling price used for each unit of accounting will be based on vendor-specific objective evidence, or VSOE, if available, third-party evidence if VSOE is not available, or estimated selling price if neither VSOE nor third-party evidence is available. We may be required to exercise considerable judgment in determining whether a deliverable is a separate unit of accounting and the estimated selling price of identified units of accounting for new or modified agreements.



Critical accounting policy	Status as of December 31, 2013

Revenue recognition - During 2013, we recognized $1.4 million of revenue under our collaboration with Takeda.	Effective April 1, 2013, we and Takeda entered into an amendment which revised the economics from a profit-sharing arrangement to a milestone and royalty-based compensation structure. The Amendment effectuated a transfer of all significant responsibilities from us to Takeda. As a result of the Amendment, Takeda assumed full responsibility for OMONTYS, including any subsequent decisions as to whether the product may be subject to reintroduction if Takeda is able to complete the investigation and address the safety concerns to the satisfaction of the FDA. We do not expect to have any future revenues unless Takeda is able to and decides to re-launch OMONTYS, which is highly uncertain. No revenues were recognized in the six-month period ended December 31, 2013.
Inventory and manufacturing commitments - During 2012, we recorded a $10.4 million charge for the write-down of inventory to a net realizable value of zero and we recorded estimated losses on firm inventory purchase commitments of $34.6 million	During 2013, we entered into a final settlement agreement with Takeda for collaboration cost reimbursement and we recognized a benefit of $43.4 million during 2013 for the resolution of the collaboration cost reimbursement and the settlements of the inventory purchase commitments. As of December 31, 2013, there are no remaining inventory balances or inventory purchase commitments.
Restructuring and asset impairment charges - During 2013, we recorded $16.1 million of restructuring costs related to a reduction of force and the exit of our leased facilities. We also recorded $4.4 million of impairment charges.	As of December 31, 2013, our restructuring activities are substantially complete. Substantially all termination payments and lease exit costs have been paid as of December 31, 2013. The remaining restructuring accrual of $0.3 million as of December 31, 2013 relates to retention bonuses for key personnel. This retention bonus is expected to be paid in 2014. During 2013, we disposed of all fixed assets in an auction and as of December 31, 2013 there are no recorded inventories or fixed assets.

We account for our Arrangement with Takeda under ASC 605-25 and currently are operating in the commercialization period as defined in the Arrangement. Before the recall, we were performing commercialization services such as promotions and marketing as well as development work related to OMONTYS post approval. In return for these services, we receive a 50/50 share of operating profit from the sale and distribution of OMONTYS (as described below), certain milestone payments and contingent payments due under the Arrangement. We also continue to receive reimbursement of costs for commercial and development costs as described in the Arrangement. Prior to approval of OMONTYS, our primary source of revenue consisted of milestone payments and Takeda’s reimbursement of commercialization and development costs.

According to the Arrangement, this includes all activities undertaken before and after regulatory approval relating specifically to commercialization services such as pre-marketing, launch promotions and marketing of OMONTYS as well as development work related to OMONTYS post approval. In return for these services, we receive a 50/50 share of operating profit from the sale and distribution of OMONTYS (as described below), certain milestone and contingent payments due under the Arrangement. We also continue to receive reimbursement of costs for commercial and development costs as described in the Arrangement. Prior to approval of OMONTYS, our primary source of revenue had consisted of milestone payments and Takeda’s reimbursement of commercialization and development costs.

In addition to the profit sharing and reimbursement of the costs described above, the Arrangement provides us the potential to earn substantive at risk milestone payments upon achievement of contractual criteria (see Note 3 of Notes to Financial Statements).

During the commercialization period, our obligations include ongoing regulatory work to obtain and maintain FDA approval and commercialization efforts related to our product launch and promotion and marketing of OMONTYS.

For each source of collaboration revenue, we apply the following revenue recognition model:

• Expense reimbursement revenue. Revenues related to reimbursements by Takeda of third-party development expenses (70/30 split per the Arrangement) and commercialization expenses (shared 50/50 according to the Arrangement) are recognized as revenue, in the period the related costs are incurred. Revenues related to reimbursement of costs of FTEs engaged in development related activities such as post-marketing studies, are recognized as revenue in the period the related costs are incurred. Such reimbursement is based on contractually negotiated reimbursement rates for each FTE as specified in the Arrangement. Subsequent to the launch of OMONTYS and recognition of product revenue by Takeda, reimbursement of commercialization expenses and development costs (both FTE and out of pocket costs) associated with post-marketing development activities, will be incorporated into the profit equalization revenue as required under the Arrangement in order to effect the 50/50 profit split, as described below.

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• Profit equalization revenue/loss. Subsequent to the launch of OMONTYS and recognition of product revenue by Takeda, Takeda allocates the quarterly profit equalization revenue/loss to us in order to effect the 50/50 profit/loss split from the sale of OMONTYS, as called for by the Arrangement. Profit equalization revenue/loss is calculated as the amount required so that the profit or loss realized by both us and Takeda on the product equates to 50% of the total product profit or loss. The profit equalization revenue/loss allocated to us from Takeda for the year ended December 31, 2012 was $26.5 million. Total product profit or loss on OMONTYS is calculated on a quarterly basis as gross product sales recorded by Takeda, less the following deductions also recorded by Takeda: rebates and discounts, cost of goods and other gross-to-net adjustments incurred by Takeda; royalty expenses incurred by us, commercialization expenses (FTE related and out of pocket costs) incurred by both Takeda and us, and certain development costs associated with post-marketing development activities (FTE related and out of pocket costs) incurred by both Takeda and us. Profit equalization revenue is recognized as revenue in the period product revenue is recognized by Takeda. As a result of the voluntary recall of OMONTYS in February 2013, all marketing activities have been suspended and there is significant uncertainty as to when or if we will be able to reintroduce OMONTYS. If the recall is not lifted and we are not able to reintroduce, this will result in a severe decrease to our profit equalization revenue or potentially, profit equalization losses, in future periods.

• API revenue. Takeda reimburses us for 120% of the external costs incurred by us to manufacture and ship commercial API for their ultimate manufacture of OMONTYS. We record the balance in deferred revenue until the earnings process is complete, which occurs when the finished goods produced from each batch of API are sold by Takeda to the end customer. As of December 31, 2012, we had a remaining balance of $17.8 million in deferred revenue related to previously expensed API. Given the uncertainty of the effects of the recall in future periods, we have recharacterized our deferred revenue as an Advance from Takeda, which is reflected as a current liability in our December 31, 2012 financial statements.

• Milestone revenue. We account for milestones under ASU No. 2010-17, Milestone Method of Revenue Recognition. Under the milestone method, contingent consideration received from the achievement of a substantive milestone is recognized in its entirety in the period in which the milestone is achieved, which we believe is more consistent with the substance of our performance under the collaboration. A milestone is defined as an event (i) that can only be achieved based in whole or in part on either the entity’s performance or on the occurrence of a specific outcome resulting from the entity’s performance, (ii) for which there is substantive uncertainty at the date the arrangement is entered into that the event will be achieved, and (iii) that would result in additional payments being due to the entity. A milestone is substantive if the consideration earned from the achievement of the milestone is consistent with our performance required to achieve the milestone or the increase in value to the collaboration resulting from our performance, relates solely to our past performance, and is reasonable relative to all of the other deliverables and payments within the collaboration. Although we are eligible to receive future milestones from Takeda, timing and amounts of future milestone payments, if any, are extremely uncertain due to the recall.

License and Royalty Revenue

Royalties are recognized as earned in accordance with contract terms, when third party results are reported and collectability is reasonably assured. Royalties received under agreements that were acquired by us in the 2001 spin out from GlaxoSmithKline or Glaxo are recorded net of the 50% that we are required to remit to Glaxo.

Inventory

We value our inventories at the lower of cost or net realizable value which is contractually determined in our collaboration with Takeda to be our cost plus a markup. We determine the cost of inventory using the specific identification method. We record API as inventory when the title transfers to us from the CMO, until the point of acceptance by Takeda. We initiate orders for API with our CMOs based on forecasts from Takeda. To date all orders have generally commenced once there was a contractual commitment for the API from Takeda.

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Neither charge reflects any future contractual reimbursements due under our collaboration arrangement with Takeda. If actual net realizable values are more favorable subsequently as a result of a reintroduction of the product, we may have favorable operating results in the future due to costs being already incurred.

We expensed costs relating to the production of API as R&D expense in the period incurred until we receive FDA approval for a new product or product configuration, and begin to capitalize the subsequent inventory costs relating to that product or product configuration. Prior to approval of OMONTYS for commercial sale in March 2012 by the FDA, we had expensed all costs associated with the production of API as R&D expense. Subsequent to receiving FDA approval of OMONTYS, we commenced capitalization of third party costs which are incurred to manufacture the API used in the production of OMONTYS.

Stock-Based Compensation

Our stock-based compensation expense for stock options is estimated at the grant date based on the award’s fair value as calculated by the Black-Scholes option pricing model and is recognized as expense over the requisite service period. The Black-Scholes option pricing model requires various highly judgmental assumptions including expected volatility and expected term. If any of the assumptions used in the Black-Scholes option pricing model changes significantly, stock-based compensation expense may differ materially in the future from that recorded in the current period. In addition, we are required to estimate the expected forfeiture rate and only recognize expense for those shares expected to vest. We estimate the forfeiture rate based on historical experience and our expectations regarding future pre-vesting termination behavior of employees. To the extent our actual forfeiture rate is different from our estimate, stock-based compensation expense is adjusted accordingly.

Income Taxes

We account for income taxes under the liability method, whereby deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to affect taxable income. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts expected to be realized.

We record liabilities related to uncertain tax positions in accordance with the guidance that clarifies the accounting for uncertainty in income taxes recognized in an enterprise's financial statements. The guidance prescribes a minimum recognition threshold and measurement process for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. We do not believe any such uncertain tax positions currently pending will have a material adverse effect on our financial statements, although an adverse resolution of one or more of these uncertain tax positions in any period could have a material impact on the results of operations for that period. We had $73.0 million, $70.6 million, and $13.1 million of unrecognized tax benefits as of December 31, 2012, 2011, and 2010, respectively.

Prior to 2012, we have experienced ownership changes as defined by Sections 382 and 383 of the Internal Revenue Code which establishes an annual limit on the deductibility of pre-ownership change net operating loss or NOL and credit carryforwards. Accordingly, we had reduced our gross deferred tax asset for the expiring carryforwards by $59.6 million as of December 31, 2011. Due to our announcement of our voluntary recall of OMONTYS in February 2013, there has been an extremely high volume of trading of our stock, which may trigger a shift of ownership amongst our 5% stockholders that could result in an ownership change (greater than 50%) as defined by the Internal Revenue Code. This could result in a significant impairment of our NOLs and potential elimination of our gross deferred tax asset, which is currently subject to our valuation allowance as it had been previously determined by management that it is more likely than not that the deferred tax asset would not be realized. We are currently in the process of assessing the impact.

At December 31, 2012, we had federal and state net operating loss carryforwards of $402.0 million and $416.0 million, respectively, before taking into consideration the annual Section 382 limitation. The federal net operating loss carryforwards begin to expire in 2028 and state net operating loss carryforwards begin to expire in 2018, if not utilized. At December 31, 2012, we had federal and state research credit carryforwards of $8.7 million and $7.0 million, respectively. The federal credits begin to expire, if not utilized, in 2022 and state credits are carried forward indefinitely.

At December 31, 2012 and 2011, our liability for uncertain income tax positions was $10.1 million and $10.4 million, respectively, and is reflected as long-term income tax liabilities on our balance sheet. Our policy is to include penalties and interest expense related to income taxes as a component of other expense and interest expense, respectively, as necessary. For the years ended December 31, 2012, 2011, and 2010, we recognized $(322,000), $144,000 and $140,000, respectively, of interest expense related to our liability for uncertain income tax positions. For the years ended December 31, 2012, 2011 and 2010, there were no penalties related to uncertain income tax positions. At December 31, 2012 and 2011, $664,000 and $986,000 was accrued for interest and penalties related to uncertain income tax positions. We do not anticipate that any of the unrecognized tax benefits will increase or decrease significantly over the next twelve months.

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Recent Accounting Pronouncements

~~Effective~~There ~~January~~are 1,no ~~2012,~~recent weaccounting ~~adopted~~pronouncements ~~revised~~which ~~guidance~~are ~~related~~expected to ~~fair~~have ~~value~~a ~~measure~~material ~~disclosure~~effect ~~that~~on ~~increases~~our ~~comparability~~financial ~~between~~condition ~~U.S. GAAP and International Financial Reporting Standards. This guidance clarifies the application of existing fair value measurement and disclosure and changes certain principles~~ or ~~requirements~~results ~~for fair value measures and disclosure. The adoption~~ of ~~this revised guidance requires expanded disclosure in our consolidated financial statements but did not impact financial results~~operations.

Effective January 1, 2012, we adopted revised guidance related to the presentation of comprehensive income that increases comparability between U.S. GAAP and International Financial Reporting Standards. We have elected to disclose comprehensive income in a separate statement in our annual report and a single continuous statement during interim reporting periods.

Item 7A. Quantitative and Qualitative Disclosure About Market Risk

~~Interest~~As ~~Rate~~of ~~Risk~~December 31, 2013, we hold no investment or marketable securities and have no debt obligations outstanding. We have no material exposure to market risk related to interest rate changes as of December 31, 2013.

~~Our exposure to market risk is confined to our cash, cash equivalents and investments~~. We do not have market risk for our debt since our outstanding debt obligations are fixed interest rate of 9.11% plus a default increase in the interest rate by an additional 500 basis points (5.0)% that may be applied to the outstanding loan balances upon the occurrence of an event of default. We do not use derivative financial instruments in our investment portfolio. The goals of our investment policy are preservation of capital, fulfillment of liquidity needs and fiduciary control of cash and investments. We also seek to maximize income from our investments without assuming significant risk. To achieve our goals, we maintain a portfolio of cash equivalents and investments in a variety of securities of high credit quality. The securities in our investment portfolio are not leveraged, are classified as available for sale and are subject to minimal interest rate risk. We currently do not hedge interest rate exposure. We do not believe that a decrease in interest rates would have a material negative impact on the value of our investment portfolio. The effect of a hypothetical decrease or increase of 10% in the average yield earned on cash, cash equivalents and investments would have resulted in an immaterial change in our interest income for the year ended December 31, 2012.

~~The table below presents the weighted-average interest rates and related carrying amounts (in thousands) of our investment portfolio as of December 31, 2012 and 2011:~~44

	2012		2011
	Weighted-averageInterest Rate	CarryingAmount	Weighted-averageInterest Rate	CarryingAmount
Cash equivalents	0.04%	$45,999	0.01%	$45,244
Short-term investments	0.36%	$9,717	0.14%	$44,165
Long-term investments	0.49%	$2,323	N/A	N/A

Foreign Exchange Risk

We have no investments denominated in foreign currencies, and therefore our investments are not subject to foreign currency exchange risk. At each quarter end, we may have liabilities for costs incurred by overseas suppliers of goods or services and clinical trial programs that are denominated in foreign currencies that are not hedged because of their relatively small size, uncertainty of payment date, and/or short time until settlement. An increase or decrease in exchange rates on these unhedged exposures may affect our operating results. However, the effect of an immediate 10% change in foreign currency rates would have no material impact on our financial condition, results of operations or cash flows as of December 31, 2012.

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Item 8. Financial Statements and Supplementary Data.

Our financial statements and notes thereto appear on pages 55 to 84 of this Annual Report on Form 10-K.




	Page
Report of Independent Registered Public Accounting Firm	46
Balance Sheets as of December 31, 2013 and 2012	47
Statements of Operations for the years ended December 31, 2013, 2012, and 2011	48
Statements of Comprehensive Loss for the years ended December 31, December 31, 2013, 2012, and 2011	49
Statements of Stockholders' Equity (Deficit) for the years ended December 31, 2013, 2012, and 2011	50
Statements of Cash Flows for the years ended December 31, December 31, 2013, 2012, and 2011	51
Notes to Financial Statements	53

	Page
Report of Ernst & Young LLP, Independent Registered Public Accounting Firm	54
Balance Sheets as of December 31, 2012 and 2011	55
Statements of Operations for the years ended December 31, 2012, 2011, and 2010	56
Statements of Comprehensive Loss for the years ended December 31, 2012, 2011, and 2010	57
Statements of Stockholders' Equity for the years ended December 31, 2012, 2011, and 2010	58
Statements of Cash Flows for the years ended December 31, 2012, 2011, and 2010	59
Notes to Financial Statements	60

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REPORT OF ~~ERNST & YOUNG LLP,~~ INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Board of Directors and Stockholders of

Affymax, Inc.

We have audited the accompanying balance sheets of Affymax, Inc. as of December 31, ~~2012~~2013 and ~~2011~~2012, and the related statements of operations, comprehensive loss, stockholders' equity (deficit), and cash flows for each of the three years in the period ended December 31, ~~2012~~2013. These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on these financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. We were not engaged to perform an audit of the Company’s internal control over financial reporting. Our audits included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, the financial statements referred to above present fairly, in all material respects, the financial position of Affymax, Inc. at December 31, ~~2012~~2013 and ~~2011~~2012, and the results of its operations and its cash flows for each of the three years in the period ended December 31, ~~2012~~2013, in conformity with U.S. generally accepted accounting principles.

The accompanying financial statements have been prepared assuming that the Company will continue as a going concern. As discussed in Note 1 to the financial statements, ~~the~~there ~~Company~~is ~~has~~significant ~~recurring~~uncertainty ~~operating~~as ~~losses with nearly all of the Company's revenues~~ to ~~date~~whether ~~resulting from~~ the ~~collaboration with Takeda Pharmaceutical~~ Company ~~Limited,~~will orhave ~~Takeda,~~sufficient ~~related~~financial resources to ~~the~~fund ~~development~~its ~~and~~operations ~~commercialization~~for ~~of OMONTYS. On February 23, 2013,~~ the ~~Company~~next ~~and~~12 ~~Takeda announced a nationwide voluntary recall of OMONTYS~~months. ~~The voluntary recall may be considered a material adverse event under the Company's loan agreement with its lenders that may result in an event of default.~~ ~~These~~This ~~conditions~~condition ~~raise~~raises substantial doubt about the Company's ability to continue as a going concern. Management's plans in regards to ~~these~~this ~~matters~~matter are also described in Note 1. The financial statements do not include any adjustments that may result from the outcome of this uncertainty.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States), Affymax, Inc.'s internal control over financial reporting as of December 31, 2012, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission and our report dated April 1, 2013 expressed an unqualified opinion thereon.




		/s/ Ernst & Young LLP

Redwood City, California

~~April~~March 131, ~~2013~~2014

5446

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AFFYMAX, INC.

BALANCE SHEETS

(in thousands, except share data)

	December 31,
	2012			2011
	2013			2012
Assets
Current assets
Cash and cash equivalents	$	685,~~265~~597		$	5468,~~339~~265
Short-term investments	~~9,717~~—			449,~~165~~717
Receivable from Takeda	~~18,365~~—			618,~~937~~365
Deferred tax assets	~~363~~—			~~351~~363
Prepaid expenses	~~2,731~~725			12,~~490~~731
Other current assets	~~3,069~~—			~~338~~3,069
Total current assets	~~102~~6,~~510~~322			~~107~~102,~~620~~510
Property and equipment, net	~~2,981~~—			32,~~013~~981
Restricted cash	~~1,135~~—			1,135
Long-term investments	~~2,323~~—			—2,323
Deferred tax assets, net of current	~~6,876~~—			6,~~888~~876
Other assets	21,~~392~~121			~~339~~2,392
Total assets	$	~~118~~7,~~217~~443		$	118,~~995~~217
Liabilities and Stockholders’ Equity
Liabilities and Stockholders’ Equity (Deficit)
Current liabilities
Accounts payable	$	~~6,591~~101		$	~~941~~6,591
Accrued liabilities	~~52,522~~581			1352,~~999~~522
Accrued clinical trial expenses	~~2,844~~—			32,~~365~~844
Deposit from Takeda	~~559~~—			~~1,998~~559
Advance from Takeda, current	27,715			—
Advance from Takeda	8,189			27,715
Notes payable, current	~~8,844~~—			—8,844
Total current liabilities	998,~~075~~871			2099,~~303~~075
Long-term income tax liability	~~10,062~~—			10,~~411~~062
Advance from Takeda, net of current	—			6,121
Other long-term liabilities	—			799
Deferred revenue, net of current	—			5,174
Total liabilities	8,871			109,936
Other long-term liabilities	799			989
Total liabilities	109,936			42,998
Commitments and contingencies (Note 9)
Stockholders’ equity
Stockholders’ equity (deficit)
Preferred Stock, $0.001 par value, 10,000,000 shares authorized, none issued and outstanding	—			—
Preferred stock, $0.001 par value, 10,000,000 shares authorized, none issued and outstanding	—			—
Common stock: $0.001 par value, 100,000,000 shares authorized, 37,369,717 and 35,733,181 shares issued and outstanding at December 31, 2012 and 2011, respectively	37			36
Common stock: $0.001 par value, 100,000,000 shares authorized, 37,490,095 and 37,396,717 shares issued and outstanding at December 31, 2013 and 2012, respectively	37			37
Additional paid-in capital	~~551~~556,~~959~~672			~~526~~551,~~244~~959
Accumulated deficit	(~~543~~558,~~713~~137		)	(~~450~~543,~~301~~713		)
Accumulated other comprehensive income	(2—		)	18(2		)
Total stockholders’ equity	8,281			75,997
Total stockholders’ equity (deficit)	(1,428		)	8,281
Total liabilities and stockholders’ equity	$	118,217		$	118,995
Total liabilities and stockholders’ equity (deficit)	$	7,443		$	118,217

The accompanying notes are an integral part of these financial statements. ~~See subsequent event in Note 1.~~

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AFFYMAX, INC.

STATEMENTS OF OPERATIONS

(in thousands, except per share data)

	Year Ended December 31,
	2012			2011			2010
	2013			2012			2011
Revenue:
Collaboration revenue	$	941,~~358~~364		$	4794,~~703~~358		$	~~112~~47,~~503~~703
License and royalty revenue	125			1712			1817
Total revenue	941,~~370~~369			4794,~~720~~370			~~112~~47,~~521~~720
Operating expenses:
Impairment of inventory and losses on firm purchase commitments	~~44,957~~—			—44,957			—
Research and development	5111,~~738~~857			7651,~~308~~738			9376,~~638~~308
Selling, general and administrative	8927,~~714~~529			3289,~~818~~714			3332,~~331~~818
Total operating expenses	186,409			109,126			126,969
Collaboration cost reimbursement	(43,451		)	—			—
Loss from operations	(92,039		)	(61,406		)	(14,448		)
Impairment (gain on disposal) of prepaid expenses, fixed assets and intangible assets	4,414			—			—
Interest income	77			169			275
2013 Restructuring charge	16,066			—			—
Interest expense	(1,442		)	(144		)	(140		)
Total operating expenses	16,415			186,409			109,126
Other income (expense), net	(34		)	15			239
Loss from operations	(15,046		)	(92,039		)	(61,406		)
Loss before provision (benefit) for income taxes	(93,438		)	(61,366		)	(14,074		)
Interest income	21			77			169
Provision (benefit) for income taxes	(26		)	1			1
Interest expense	(1,565		)	(1,442		)	(144		)
Net loss	$	(93,412	)	$	(61,367	)	$	(14,075	)
Other income (expense), net	8			(34		)	15
Loss before provision (benefit) for income taxes	(16,582		)	(93,438		)	(61,366		)
Provision (benefit) for income taxes	(2,158		)	(26		)	1
Net loss	$	(14,424	)	$	(93,412	)	$	(61,367	)
Net loss per share:
Basic and diluted	$	(20.5739	)	$	(12.8457	)	$	(01.5784	)
Weighted-average number of shares used in computing basic and diluted net loss per share	3637,~~342~~448			3336,~~288~~342			2433,~~488~~288

The accompanying notes are an integral part of these financial statements.

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AFFYMAX, INC.

STATEMENTS OF COMPREHENSIVE LOSS

(in thousands)

	Year Ended December 31,
	2012			2011			2010
	2013			2012			2011
Net loss	$	(9314,~~412~~424	)	$	(6193,~~367~~412	)	$	(1461,~~075~~367	)
Other comprehensive income (loss):
Other comprehensive loss:
Change in unrealized gains (losses) on investments	~~(20~~2		)	(1320		)	~~183~~(13		)
Reclassification adjustment for (gains) losses on investments recognized in earnings	—			—			(97		)
Other comprehensive loss	2			(20)			(13)
Other comprehensive income (loss)	$	(20	)	$	(13	)	$	86
Comprehensive loss	$	(14,422	)	$	(93,432	)	$	(61,380	)
Comprehensive loss	$	(93,432	)	$	(61,380	)	$	(13,989	)

The accompanying notes are an integral part of these financial statements.

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AFFYMAX, INC.

STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT)

(in thousands, except share data)

				AdditionalPaid-InCapital			DeferredStock-BasedCompensation			AccumulatedDeficit			Accumulated Other Comprehensive Income (Loss)			Total Stockholder's Equity
	Shares	Amount
Balance at December 31, 2009	23,869,095	$	24	$	441,795		$	—		$	(374,859	)	$	(55	)	$	66,905
Balance at December 31, 2010	25,451,338	$	25	$	461,425		$	—		$	(388,934	)	$	31		$	72,547
Issuance of common stock upon exercise of stock options	399,323	—		2,243			—			—			—			2,243
Issuance of common stock upon vesting of restricted stock units	53,544	—		—			—			—			—			—
Proceeds from common stock issued upon private placement, net of issuance costs	999,061	1		4,882			—			—			—			4,883
Issuance of common stock related to the employee stock purchase plan	130,315	—		982			—			—			—			982
Deferred stock-based compensation	—	—		(379		)	379			—			—			—
Amortization of deferred stock-based compensation	—	—		—			(379		)	—			—			(379		)
Employee stock-based compensation	—	—		12,193			—			—			—			12,193
Nonemployee stock-based compensation	—	—		(291		)	—			—			—			(291		)
Other comprehensive income	—	—		—			—			—			86			86
Net loss	—	—		—			—			(14,075		)	—			(14,075		)
Balance at December 31, 2010	25,451,338	25		461,425			—			(388,934		)	31			72,547
Issuance of common stock upon exercise of stock options	95,917	—		371			—			—			—			371
Issuance of common stock upon vesting of restricted stock units	255,782	—		—			—			—			—			—
Proceeds from common stock issued upon public offering, net of issuance costs	9,745,762	10		53,615			—			—			—			53,625
Issuance of common stock related to the employee stock purchase plan	184,382	1		807			—			—			—			808
Deferred stock-based compensation	—	—		(5		)	5			—			—			—
Amortization of deferred stock-based compensation	—	—		—			(5		)	—			—			(5		)
Employee stock-based compensation	—	—		9,773			—			—			—			9,773
Nonemployee stock-based compensation related to consultants	—	—		(10		)	—			—			—			(10		)
Nonemployee stock-based compensation related to former CEO	—	—		268			—			—			—			268
Change in unrealized loss on marketable securities	—	—		—			—			—			(13		)	(13		)
Net loss	—	—		—			—			(61,367		)	—			(61,367		)
Balance at December 31, 2011	35,733,181	36		526,244			—			(450,301		)	18			75,997
Issuance of common stock upon exercise of stock options	1,129,422	1		12,028			—			—			—			12,029
Issuance of common stock upon vesting of restricted stock units	222,093	—		—			—			—			—			—
Issuance of common stock related to the employee stock purchase plan	224,908	—		1,082			—			—			—			1,082
Issuance of warrants related to Loan and Security Agreement	—	—		1,394			—			—			—			1,394
Issuance of common stock upon net exercise of warrants	60,113	—		—			—			—			—			—
Deferred stock-based compensation	—	—		87			(87		)	—			—			—
Amortization of deferred stock-based compensation	—	—		—			87			—			—			87
Employee stock-based compensation	—	—		11,055			—			—			—			11,055
Nonemployee stock-based compensation	—	—		69			—			—			—			69
Change in unrealized loss on marketable securities	—	—		—			—			—			(20		)	(20		)
Net loss	—	—		—			—			(93,412		)	—			(93,412		)
Balance at December 31, 2012	37,369,717	$37	37	$551,959	~~551,959~~		$—	—		$(543,713	~~(543,713~~	)	$(2	(2	)	$8,281	~~8,281~~
Issuance of common stock upon exercise of stock options	30,918	—		271			—			—			—			271
Issuance of common stock upon vesting of restricted stock units	89,460	—		—			—			—			—			—
Deferred stock-based compensation	—	—		(3		)	3			—			—			—
Amortization of deferred stock-based compensation	—	—		—			(3		)	—			—			(3		)
Employee stock-based compensation	—	—		4,445			—			—			—			4,445
Change in unrealized loss on marketable securities	—	—		—			—			—			2			2
Net loss	—	—		—			—			(14,424		)	—			(14,424		)
Balance at December 31, 2013	37,490,095	$	37	$	556,672		$	—		$	(558,137	)	$	—		$	(1,428	)

The accompanying notes are an integral part of these financial statements.

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AFFYMAX, INC.

STATEMENTS OF CASH FLOWS

(in thousands)

	Year ended December 31,
	2012			2011			2010
	2013			2012			2011
Cash flows from operating activities
Net loss	$	(9314,~~412~~424	)	$	(6193,~~367~~412	)	$	(1461,~~075~~367	)
Adjustments to reconcile net loss to net cash used in operating activities:
Impairment of inventory and losses on firm purchase commitments	44,957			—			—
Collaboration cost reimbursement	(43,451		)	—			—
Depreciation and amortization	1,987			2,182			2,212
Impairment of prepaid expenses, fixed assets and intangible assets	5,118			—			—
Amortization of premium on investments	75			55			650
Noncash restructuring charge	307			—			—
Stock-based compensation expense	11,211			10,025			11,523
Impairment of inventory and losses on firm purchase commitments	—			44,957			—
Loss on disposal of property and equipment	30			11			2
Depreciation and amortization	722			1,987			2,182
Noncash interest expense	827			144			140
Amortization of premium on investments	1			75			55
Stock-based compensation expense	4,442			11,211			10,025
Loss on (gain) on disposal of property and equipment	(704		)	30			11
Noncash interest expense	811			827			144
Changes in operating assets and liabilities:
Receivable from Takeda	(918,~~600~~365		)	(69,~~937~~600		)	18(6,~~561~~937		)
Income tax receivable	—			—			1,443
Inventory	—			(4,515		)	—
Inventory	(4,515		)	—			—
Prepaid expenses	(441		)	(5,085		)	272
Prepaid expenses	(5,085		)	272			1,069
Other current assets	3,028			(2,732		)	(77		)
Other current assets	(2,732		)	(77		)	5,612
Other noncurrent assets	73			(2		)	(289		)
Other noncurrent assets	(2		)	(289		)	342
Accounts payable	(6,490		)	5,650			620
Accounts payable	5,650			620			(143		)
Accrued liabilities	(28,335		)	3,849			2,405
Accrued liabilities	3,849			2,405			(1,000		)
Accrued clinical trial expenses	(2,844		)	(521		)	(7,882		)
Accrued clinical trial expenses	(521		)	(7,882		)	(28,252		)
Payable to Takeda	—			—			(5,958		)
Payable to Takeda	—			(5,958		)	5,958
Deferred revenue	—			(5,174		)	(13,322		)
Deferred revenue	(5,174		)	(13,322		)	(53,475		)
Deposit from Takeda	(559		)	(1,438		)	1,998
Deposit from Takeda	(1,438		)	1,998			—
Long-term income tax liability	(2,159		)	(27		)	18
Long-term income tax liability	(27		)	18			—
Advance from Takeda	—			17,767			6,121
Advance from Takeda	17,767			6,121			—
Other long-term liabilities	(799		)	(1,027		)	15
Other long-term liabilities	(1,027		)	15			199
Net cash used in operating activities	(67,339		)	(37,180		)	(71,966		)
Net cash used in operating activities	(37,180		)	(71,966		)	(49,234		)
Cash flows from investing activities
Purchases of property and equipment	~~(1,562~~—		)	(1,~~265~~562		)	(~~730~~1,265		)
Payments for of intellectual property license	~~(2,500~~—		)	—(2,500		)	—
Purchases of investments	~~(13,233~~—		)	(3513,~~799~~233		)	(~~128~~35,~~650~~799		)
Proceeds from sale of investments	—13,175			—			~~16,042~~—
Proceeds from maturities of investments	45,265			45,024			101,857
Proceeds from maturities of investments and restricted cash	—			45,265			45,024
Proceeds from sale of property and equipment	251,225			4125			241
Net cash provided by (used in) investing activities	27,995			8,001			(11,479		)
Net cash provided by investing activities	14,400			27,995			8,001
Cash flows from financing activities
Proceeds from issuance of common stock upon exercise of stock options	~~12,029~~271			~~371~~12,029			~~2,243~~371
Proceeds from issuance of common stock under employee stock purchase plan	~~1,082~~—			~~809~~1,082			~~982~~809
Proceeds from common stock issued upon private placement, net of issuance costs	—			—			~~4,883~~—
Proceeds from common stock issued upon public offering, net of issuance costs	—			~~53,625~~—			—53,625
Repayment of UBS loan	—			—			(9,192		)
Repayment of notes payable	(10,000		)	—			—
Proceeds from notes payable	~~10,000~~—			—10,000			—
Net cash provided by (used in) financing activities	23(9,~~111~~729		)	5423,~~805~~111			(154,~~084~~805		)
Net increase (decrease) in cash and cash equivalents	13(62,~~926~~668		)	(913,~~160~~926		)	(619,~~797~~160		)
Cash and cash equivalents at beginning of the period	5468,~~339~~265			6354,~~499~~339			~~125~~63,~~296~~499
Cash and cash equivalents at end of the period	$	685,~~265~~597		$	5468,~~339~~265		$	6354,~~499~~339
Supplemental disclosures of cash flow information:
Income taxes paid	$	1		$	1		$	1
Interest paid	$	~~615~~792		$	—615		$	—
Supplemental schedule of non-cash financing activities:
Advance from Takeda	$	~~1,828~~—		$	—1,828		$	—
Change in unrealized gain (loss) on investments	$	~~(20~~2	)	$	(1320	)	$	86(13	)
Deferred stock-based compensation, net of cancellations	$	873		$	(587	)	$	(~~379~~5	)
Warrants issued in connection with notes payable	$	~~1,394~~—		$	—1,394		$	—

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The accompanying notes are an integral part of these financial statements.

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AFFYMAX, INC.

NOTES TO FINANCIAL STATEMENTS

1. The Company

Affymax, Inc., a Delaware corporation, was incorporated in July 2001. We are a biopharmaceutical company committed to discovering, developing and delivering innovative therapies that improve the lives of patients with kidney disease and other serious and often life-threatening illnesses. In March 2012, the U.S. Food and Drug Administration, or FDA, approved ~~the~~our ~~company’s~~ first and only product, OMONTYS® (peginesatide) Injection for the treatment of anemia due to chronic kidney disease in adult patients on dialysis. OMONTYS is a synthetic, peptide-based erythropoiesis stimulating agent, or ESA, designed to stimulate production of red blood cells and ishas been the only once-monthly ESA ~~currently~~ available to the adult dialysis patient population in the U.S. We ~~are~~ co-~~commercializing~~commercialized OMONTYS with our collaboration partner, Takeda Pharmaceutical Company Limited, or Takeda ~~and~~during ~~we launched the product in April~~ 2012~~. In~~ until February 2013, when we and Takeda announced a nationwide voluntary recall of OMONTYS as a result of safety concerns. ~~See~~ ~~further~~Effective ~~discussion~~April ~~below~~1, 2013, we entered into an amendment of our collaboration agreement with Takeda pursuant to which Takeda assumed full responsibility for OMONTYS, including responsibility for the ongoing recall and investigation with the FDA, and we granted them an exclusive worldwide license to OMONTYS in consideration for potential milestones and royalties.

We have experienced significant operating losses since inception. We ~~have~~The ~~funded~~recall of OMONTYS has severely harmed our ~~operations~~business, ~~primarily~~financial ~~through~~condition, and prospects as a going concern and even with the ~~sale~~transition of ~~equity~~responsibilities ~~securities,~~effectuated ~~reimbursement~~by ~~for~~the ~~development~~Takeda ~~expenses~~amendment and ~~active~~the ~~pharmaceutical~~reductions ~~ingredient~~in force, orthese ~~API,~~planned ~~production,~~cost ~~license~~reductions ~~fees,~~may ~~milestone~~not ~~payments~~be ~~and~~sufficient ~~profit~~for ~~equalization~~us ~~revenue~~to ~~payments~~continue ~~from~~as a going concern. The recall has also limited our ~~collaborative~~access ~~partner~~to ~~Takeda,~~funds. ~~issuance~~We ofmay ~~notes~~be ~~payable,~~unable ~~operating~~to continue our operations or to succeed in the existing and ~~capital~~potential ~~lease~~future ~~financings~~litigation, ~~interest~~particularly ~~earned~~with onthe ~~investments~~reductions in force and ~~limited~~in ~~license~~view ~~fees~~of our limited resources and ~~royalties~~funds. ~~from~~We ~~licensing~~may ~~intellectual~~explore ~~property~~various strategic alternatives, including a sale of the Company or our assets or a corporate merger. We are considering all possible alternatives, including wind-down of operations or bankruptcy proceedings. As of December 31, ~~2012~~2013, we had an accumulated deficit of $~~543~~558.71 million.

Subsequent Event

Product Recall

In connection with the recall and in consultation with Takeda, we have undertaken efforts to suspend manufacturing activities to the extent practicable pending consideration of next steps with OMONTYS. If we are successful in identifying the cause of these recent safety concerns and addressing it, we and Takeda will determine the next appropriate steps to take with OMONTYS. Prior to such time, we plan to evaluate strategies to decrease our ongoing manufacturing costs and commitments, including but not limited to, termination of orders and agreements. However, in order to reintroduce OMONTYS, we would have to complete our ongoing and thorough investigation, identify the causes of the safety concerns and provide a suitable plan to the FDA for approval. Accordingly, there can be no assurance that we can address the safety concerns and meet the requirements of the FDA for reintroduction. Moreover, even if OMONTYS could be reintroduced, the commercial prospects for this product may be permanently diminished and the product may no longer be commercially viable.

Given the nature and significance of the product recall, in connection with the preparation of our 2012 financial statements we have reviewed account balances subject to estimation at December 31, 2012, including inventory and inventory purchase commitment obligations, for which we perform a lower of cost or market analysis. We have recorded adjustments to our financial statements to reflect changes in our estimates as to the recoverability of inventory and deposits made to our contract manufacturing organizations, or CMOs, loss on firm purchase commitments and changes in the short-term and long-term classification of certain liabilities. We have provided additional disclosure as appropriate. See Notes 2, 3, 5, and 8 of the Notes to the Financial Statements.

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Restructuring

In March 2013, we commenced a re-organization plan to reduce operating costs, which included a reduction in force of approximately 230 employees. We expect to incur between $8.0 million and $10.0 million in restructuring charges, all of which are related to expenditures for one-time employee termination benefits. We expect to incur most of the charges during the first quarter of 2013. As a result of this restructuring and the recall, we may also experience impairment changes with respect to our property and equipment and long lived assets our license from Janssen Biotech, Inc. (a subsidiary of Johnson & Johnson) and certain of its affiliated companies, collectively referred to as Janssen, in the first quarter of 2013.

Going Concern

~~The~~Because we have not made an irrevocable decision to liquidate, the accompanying financial statements have been prepared onunder the assumption of a going concern basis that contemplates the realization of assets and liabilities in the ordinary course of business. Operating losses have been incurred each year since inception, resulting in an accumulated deficit of $~~543~~558.71 million as of December 31, ~~2012~~2013. Nearly all of our revenues to date have come from our collaboration with Takeda. As a result of the February 23, 2013 nationwide voluntary recall of OMONTYS and the suspension of all marketing activities, there is significant uncertainty as to whether we will have sufficient existing cash, ~~cash equivalents and investments~~ to fund our operations ~~for the next 12 months~~. ~~Even~~ ~~with~~As ~~the~~of ~~recent~~December ~~reorganization~~31, ~~further~~2013 ~~reductions~~we inhave ~~our~~cash ~~workforce~~of $5.6 million and ~~cash~~current ~~flows,~~liabilities ~~there~~of is$8.9 nomillion. We ~~assurance~~believe that weour cash will be ~~able~~sufficient to ~~reduce~~fund our ~~operating~~operations ~~expenses~~through ~~enough~~the tothird ~~meet~~quarter ~~our~~of ~~existing~~2014, ~~obligations~~but ~~and~~there ~~conduct~~is ~~ongoing~~significant ~~operations. If~~uncertainty weas ~~do not have sufficient funds~~ to ~~continue~~whether ~~operations,~~our wecash ~~could~~will be ~~required~~sufficient to ~~liquidate~~fund our ~~assets,~~operations ~~seek~~past ~~bankruptcy~~the ~~protection~~third orquarter ~~other~~of ~~alternatives~~2014. ~~Further,~~ weGiven ~~may be in breach under~~ our ~~loan~~limited ~~and security agreement~~resources, orthere ~~the~~is ~~Loan~~no ~~Agreement,~~assurance ~~with~~that ~~Oxford~~we ~~Finance~~will ~~LLC and Silicon Valley Bank, or the Lenders, as the voluntary recall may~~ be ~~considered~~able ato ~~material~~reduce ~~adverse~~our ~~event~~operating ~~under~~expenses ~~the~~enough ~~Loan Agreement. Under the loan agreement the Lenders have various rights including the ability~~ to ~~require~~meet ~~immediate~~our ~~repayment~~existing ~~of the outstanding principal plus accrued~~ and ~~unpaid~~future ~~interest,~~obligations ~~a final payment fee~~ and aconduct ~~prepayment fee (see further discussion in Note 8 of the Notes to the Financial Statements below). We expect to incur substantial expenses associated with the recall and the~~ ongoing ~~investigation~~operations. ~~Even~~ If ifwe ~~the~~do ~~underlying~~not ~~causes~~have ofsufficient ~~the~~funds ~~safety concerns can be identified, which is uncertain, the timelines associated with the investigation and the feasibility and costs associated with implementing solutions~~ to ~~address~~continue ~~the safety concerns to the satisfaction of the FDA are highly uncertain. Accordingly~~operations, we ~~may~~could ~~never~~ be ~~able~~required to ~~reintroduce~~liquidate ~~OMONTYS~~our ~~or generate significant revenues and~~assets, ~~even~~seek ifbankruptcy ~~OMONTYS~~protection ~~is reintroduced so as to generate product sales, we may never achieve~~ or ~~sustain~~other ~~profitability~~alternatives. ~~Any~~ ~~failure~~Further, togiven ~~dispel~~our ~~any~~limited ~~continuing~~resources, ~~doubts about~~ our ~~ability~~cash tomay ~~continue~~not asbe asufficient ~~going~~to ~~concern~~fund ~~could~~operations ~~adversely~~through ~~affect~~the ~~our~~third ~~ability~~quarter toif ~~enter~~unforeseen ~~into~~events ~~collaborative~~occur ~~relationships~~that ~~with~~require ~~business~~additional ~~partners~~cash expenditures. These matters raise substantial doubt about our ability to continue as a going concern. Our financial statements do not include any adjustments that may result from the outcome of this uncertainty.

2. Summary of Significant Accounting Policies

Concentration of Risk

Our future revenue is based on only one source of product-related revenue, OMONTYS which has bee recalled/discontinued. If Takeda is not successful in identifying the cause of the recall and is unable or unwilling to reintroduce OMONTYS, we have no prospects for other sources of revenue.

Use of Estimates

The preparation of financial statements in conformity with U.S. generally accepted accounting principles, or GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure ~~of contingent liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates.~~

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of contingent liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates.

Cash and Cash Equivalents

Cash and cash equivalents are stated at cost, which approximates market value. We consider all highly liquid investments purchased with an original maturity of three months or less to be cash equivalents.

Restricted Cash

~~Restricted~~There ~~cash~~is ~~represents~~no restricted cash ~~for certificates of deposit provided~~ as ~~credit guarantees and security for an irrevocable letter~~ of ~~credit~~December ~~related~~31, ~~to the lease of office space~~2103.

Reclassifications

Certain amounts in prior period financial statements have been reclassified to conform to the current period presentation. We reclassified $537,000 to accrued liabilities from other long-term liabilities in the 2011 balance sheet. These reclassifications did not change previously reported net loss, total assets, or stockholders’ equity.

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Concentration of Risk

Financial instruments that potentially subject us to a concentration of credit risk consist of cash, cash equivalents and investments. We deposit excess cash in accounts with major financial institutions in the U.S. Deposits in these banks may exceed the amount of insurance provided on such deposits. We have not experienced any realized losses on our deposits of cash and cash equivalents.

As of December 31, 2012 and December 31, 2011 our accounts receivable balance with Takeda was $18.4 million and $6.9 million, respectively. The receivable is comprised of the amounts due from Takeda under our Arrangement with them. We have not experienced any credit losses from our receivables with Takeda and none are expected. We do not require collateral on our receivable. The receivable balance as of December 31, 2012 has been collected in full subsequent to year end.

To achieve profitable operations, we and Takeda must successfully manufacture and commercialize OMONTYS. There can be no assurance that OMONTYS can be manufactured at an acceptable cost and with appropriate performance characteristics on a consistent and reliable basis, or that OMONTYS will be successfully commercialized, when and if OMONTYS is reintroduced. These factors could have a material adverse effect on our future financial results.

Further, some of our and Takeda’s operations, suppliers and manufacturing arrangements are currently single-sourced, leaving us at greater risk of supply interruptions, potential delays and failure to commercialize, when and if OMONTYS is reintroduced. Due to the product recall of OMONTYS, we have undertaken efforts to suspend or terminate manufacturing activities to the extent practicable pending consideration of next steps with OMONTYS. If for any reason these third parties are unable or unwilling to perform under our agreements or enter into new agreements with us, we may not be able to locate alternative manufacturers or enter into favorable agreements with them in an expeditious manner. Any inability to acquire sufficient quantities of OMONTYS or components thereof in a timely manner from third parties could result in product shortages, delays in clinical trials and could prevent us from commercializing OMONTYS in a cost-effective manner or on a timely basis. This could result in further losses and reduced profits that we share in from the sale of OMONTYS.

Revenue Recognition

Collaboration Revenue

We recognize revenue for contracts entered into prior to 2011 in accordance with the SEC Staff Bulletin No. 101, Revenue Recognition in Financial Statements, as amended by Staff Accounting Bulletin or SAB, No. 104, Revision of Topic 13 and Accounting Standards Codification or ASC, 605-25, Multiple Element Arrangements. When evaluating multiple element arrangements, we consider whether the components of the arrangement represent separate units of accounting as defined in the authoritative guidance for revenue arrangements with multiple deliverables. Application of this guidance requires subjective determinations and requires management to make judgments about the fair value of the individual elements and whether such elements are separable from the other aspects of the contractual relationship. We continue to follow the guidance of ASC 605-25 to determine whether the components of the Arrangement represent separate units of accounting. To determine if a delivered item can be treated as a separate unit of accounting, we evaluate (1) if the delivered item(s) has value to Takeda on a standalone basis; (2) there is objective and reliable evidence of fair value of the undelivered item(s) and (3) if a general right of return exists for the delivered item (e.g. contingencies), delivery or performance of the undelivered item(s) is considered probable and is substantially within the control of the company. We recognize revenue for contracts entered into or materially modified after January 1, 2011, in accordance with Accounting Standards Update, or ASU, No. 2009-13, Multiple Deliverable Revenue Arrangements. This update amends the guidance on accounting for arrangements with multiple deliverables to require that each deliverable be evaluated to determine whether it qualifies as a separate unit of accounting. This determination is generally based on whether the deliverable has stand-alone value to the customer. This update also establishes a selling price hierarchy for determining how to allocate arrangement consideration to identified units of accounting. The selling price used for each unit of accounting will be based on vendor-specific objective evidence, or VSOE, if available, third-party evidence if VSOE is not available, or estimated selling price if neither VSOE nor third-party evidence is available. We may be required to exercise considerable judgment in determining whether a deliverable is a separate unit of accounting and the estimated selling price of identified units of accounting for new or modified agreements.

We account for our Arrangement with Takeda under ASC 605-25 and currently, are operating in the commercialization period as defined in the Arrangement. Before the recall, we were performing commercialization services such as promotions and marketing as well as development work related to OMONTYS post approval. In return for these services, we receive a 50/50 share of operating profit from the sale and distribution of OMONTYS (as described below), certain milestone payments and contingent payments due under the Arrangement. We also continue to receive reimbursement of costs for commercial and development costs as described in the Arrangement. Prior to approval of OMONTYS, our primary source of revenue consisted of milestone payments and Takeda’s reimbursement of commercialization and development costs.

62In addition to the profit sharing and reimbursement of the costs described above, the Arrangement provided us the potential to earn substantive at risk milestone payments upon achievement of contractual criteria (see Note 3 of Notes to Financial Statements). However, timing and amounts of these milestones are extremely uncertain due to the recall.

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development costs as described in the Arrangement. Prior to approval of OMONTYS, our primary source of revenue consisted of milestone payments and Takeda’s reimbursement of commercialization and development costs.

For each source of collaboration revenue, we apply the following revenue recognition model:

• Expense reimbursement revenue. Revenues related to reimbursements by Takeda of third-party development expenses (70/30 split per the Arrangement) and commercialization expenses (shared 50/50 according to the Arrangement) are recognized as revenue, in the period the related costs are incurred. Revenues related to reimbursement of costs of full-time equivalents, or FTEs, engaged in development related activities such as post-marketing studies, are recognized as revenue in the period the related costs are incurred. Such reimbursement is based on contractually negotiated reimbursement rates for each FTE as specified in the Arrangement. Subsequent to the launch of OMONTYS and recognition of product revenue by Takeda, reimbursement of commercialization expenses and development costs (both FTE and out of pocket costs) associated with post-marketing development activities, is incorporated into the profit equalization revenue as required under the Arrangement in order to effect the 50/50 profit split, as described below.

• Profit equalization revenue/loss. Subsequent to the launch of OMONTYS and recognition of product revenue by Takeda, Takeda allocates the quarterly profit equalization revenue/loss to us in order to effect the 50/50 profit/loss split from the sale of OMONTYS, as called for by the Arrangement. Profit equalization revenue/loss is calculated as the amount required so that the profit or loss realized by both usand Takeda on the product equates to 50% of the total product profit or loss. Total product profit or loss on OMONTYS is calculated on a quarterly basis as gross product sales recorded by Takeda, less the following deductions also recorded by Takeda: rebates and discounts, cost of goods, and other gross-to-net adjustments incurred by Takeda; royalty expenses incurred by us, commercialization expenses (FTE related and out of pocket costs) incurred by both Takeda and us, and certain development costs associated with post-marketing development activities (FTE related and out of pocket costs) incurred by both Takeda and us. Profit equalization revenue is recognized as revenue in the period product revenue is recognized by Takeda. As a result of the voluntary recall of OMONTYS in February 2013, all marketing activities have been suspended. If the recall is not lifted and we are not able to reintroduce, this will result in a severe decrease to our profit equalization revenue or potentially, profit equalization losses, in future periods.54

•Table ~~API revenue. Takeda reimburses us for 120%~~ of the external costs incurred by us to manufacture and ship commercial API for their ultimate manufacture of OMONTYS. Werecord the balance in deferred revenue until the earnings process is complete, which occurs when the finished goods produced from each batch of API are sold by Takeda to the end customer. As of December 31, 2012 we had a remaining balance of $17.8 million in deferred revenue related to previously expensed API. Given the uncertainty of the effects of the recall and the return of product containing the API that followed the recall, we have recharacterized our deferred revenue as an Advance from Takeda, which is reflected as a current liability in our December 31, 2012 financial statements.Contents

marketing studies, are recognized as revenue in the period the related costs are incurred. Such reimbursement is based on contractually negotiated reimbursement rates for each FTE as specified in the Arrangement. Subsequent to the launch of OMONTYS and recognition of product revenue by Takeda, reimbursement of commercialization expenses and development costs (both FTE and out of pocket costs) associated with post-marketing development activities, is incorporated into the profit equalization revenue as required under the Arrangement in order to effect the 50/50 profit split, as described below. As part of the Amendment with Takeda, both Parties agreed that they will no longer share expenses related to third-party development (70/30 split) and commercialization (50/50 split) as of April 1, 2013. Except for certain transition services that we performed in April 2013 for full reimbursement of $0.5 million, any expenses incurred by either us or Takeda after April 1, 2013 shall be the responsibility of the respective party and neither us or Takeda has the obligation to share expenses with each other.

•

Profit equalization revenue/loss. Subsequent to the launch of OMONTYS and prior to the Amendment, as to the recognition of product revenue by Takeda, Takeda allocates the quarterly profit equalization revenue/loss to us in order to effect the 50/50 profit/loss split from the sale of OMONTYS, as called for by the Arrangement. Profit equalization revenue/loss is calculated as the amount required so that the profit or loss realized by both us and Takeda on the product equates to 50% of the total product profit or loss. Total product profit or loss on OMONTYS is calculated on a quarterly basis as gross product sales recorded by Takeda less the following deductions also recorded by Takeda: rebates and discounts, cost of goods, and other gross-to-net adjustments incurred by Takeda; royalty expenses incurred by us, commercialization expenses (FTE related and out of pocket costs) incurred by both Takeda and us, and certain development costs associated with post-marketing development activities (FTE related and out of pocket costs) incurred by both Takeda and us. Profit equalization revenue is recognized as revenue in the period product revenue is recognized by Takeda. As a result of the voluntary recall of OMONTYS in February 2013, all marketing activities were suspended. As part of the Amendment with Takeda, the profit equalization revenue for the three months ended March 31, 2013 will be the final profit equalization payment under the Arrangement. Upon signing the Amendment with Takeda, the economics of the collaboration changed from a profit sharing arrangement to a milestone and royalty-based compensation structure to us, effective April 1, 2013.

•

Milestone revenue. We account for milestones under ASU No. 2010-17, Milestone Method of Revenue Recognition. Under the milestone method, contingent consideration received from the achievement of a substantive milestone is recognized in its entirety in the period in which the milestone is achieved, which we believe is more consistent with the substance of our performance under the collaboration. A milestone is defined as an event (i) that can only be achieved based in whole or in part on either the entity’s performance or on the occurrence of a specific outcome resulting from the entity’s performance, (ii) for which there is substantive uncertainty at the date the arrangement is entered into that the event will be achieved, and (iii) that would result in additional payments being due to the entity. A milestone is substantive if the consideration earned from the achievement of the milestone is consistent with our performance required to achieve the milestone or the increase in value to the collaboration resulting from our performance, relates solely to our past performance, and is reasonable relative to all of the other deliverables and payments within the collaboration. Although we are eligible to receive future milestones from Takeda, timing and amounts of future milestone payments, if any are extremely uncertain due to the recall.

63 Below is a summary of the components of our collaboration revenue for the years ended December 31, 2013, 2012, and 2011 (in thousands):



	Year ended December 31,
	2013		2012		2011
Profit equalization revenue	$	5	$	26,544	$	—
Milestone payments	—		60,250		10,000
Revenue previously deferred related to API	—		936		—
Revenue recognized under CAPM	—		—		26,606
Net expense reimbursement after CAPM	1,364		6,628		11,097
Total collaboration revenue	$	1,369	$	94,358	$	47,703

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During the development period under the Arrangement with Takeda, which ended upon the submission of our New Drug Application or NDA to the FDA for review, collaboration revenue was recognized using the Contingency Adjusted Performance Model or CAPM. As a result, any payments from Takeda under the Arrangement were recorded as deferred revenue and recognized ratably over the estimated development period. Below is a summary of the components of our collaboration revenue for the years ended December 31, 2012, 2011, and 2010 (in thousands):

	Year ended December 31,
	2012		2011		2010
Profit equalization revenue	$	26,544	$	—	$	—
Milestone payments	60,250		10,000		—
Revenue previously deferred related to API	936		—		—
Revenue recognized under CAPM	—		26,606		112,503
Net expense reimbursement after CAPM	6,628		11,097		—
Total collaboration revenue	$	94,358	$	47,703	$	112,503

License and Royalty Revenue

If Takeda decides to reintroduce OMONTYS, which is highly uncertain, we are eligible to receive potential milestones and royalties. The royalties are tiered in the range of 13% to 17% with respect to net sales in the U.S. and in the range of 13% to 24% depending on the level of net sales by Takeda worldwide outside of the U.S.

Fair Value of Financial Instruments

For financial instruments consisting of cash and cash equivalents, receivable from Takeda, advance from Takeda, accounts payable, deposit from Takeda and accrued liabilities included in our financial statements, the carrying amounts are reasonable estimates of fair value due to their short maturities. Estimated fair values for short-term and long-term investments are based on quoted market prices for the same or similar instruments. Based on borrowing rates currently available to us for loans with similar terms, the carrying value of lease obligations approximates fair value.

Inventory

We analyze our inventory levels quarterly and write down inventory that has become obsolete or has a cost basis in excess of its expected net realizable value, as well as any inventory quantities in excess of expected requirements ~~at December 31, 2012~~. Any expired inventory is disposed of and the related costs are recognized as expense. The voluntary recall of OMONTYS in February 2013, impacted the recoverability of our inventories based on assumptions about expected demand and net realizable value. AsIn of the ~~filing~~December ~~date~~31, 2012 balance sheet, given the significant uncertainty of demand following the recall, we ~~have~~had written down our API inventory and prepayments made to our CMOs to the net realizable value of zero ~~and have recorded an $10~~.~~4 million impairment charge related to this writedown.~~ We ~~have~~ also established an accrual for estimated losses on firm inventory purchase commitments ~~of $34.6 million~~ by applying the same lower of cost or market approach that is used to value inventory. ~~Neither~~As ~~charge~~of ~~reflects~~March ~~any~~31, ~~future~~2013 ~~contractual~~this ~~reimbursements~~accrued ~~due~~commitment ~~under~~was ~~our~~$32.9 ~~collaboration arrangement with Takeda~~million. IfHowever, ~~actual~~in ~~net~~the ~~realizable~~second ~~values~~quarter ~~are~~of ~~more~~2013, ~~favorable~~we ~~subsequently~~were asable ato ~~result~~settle ofthese aobligations ~~reintroduction~~for of$11.0 ~~the~~million ~~product,~~resulting wein ~~may~~a ~~have~~ favorable adjustment to our operating results of $21.9 million in the ~~future~~quarter ~~due~~ended toJune ~~costs~~30, ~~being~~2013. As ~~already~~of ~~incurred~~December 31, 2013, there was no remaining manufacturing obligations or accrued balance.

We expense costs relating to the production of API as research and development or R&D expense in the period incurred until we receive FDA approval for a new product or product configuration and began to capitalize the subsequent inventory costs relating to that product or product configuration. Prior to approval of OMONTYS for commercial sale in March 2012 by the FDA, we had expensed all costs associated with the production of API as R&D expense. Subsequent to receiving FDA approval of OMONTYS, we commenced capitalization of third party costs which are incurred to manufacture the API used in the production of OMONTYS.

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Investments

Investments are classified as available-for-sale and are carried at their fair market value based upon quoted market prices for these or similar instruments at the balance sheet date. Unrealized gains and losses are reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity until realized. Debt securities are adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization as well as realized gains and losses are included in interest income. We assess our investments for potential other-than-temporary impairment based on factors including the length of time and extent to which the fair market value has been below our cost basis, the current financial condition of the investee and our intent and ability to hold the investment for a sufficient period of time to allow for any anticipated recovery in market value. If we conclude that an other-than-temporary impairment exists, we recognize an impairment charge to reduce the investment to fair value and record the related charge as a reduction of interest to other income (expense), net. We have elected to use settlement date accounting for purposes of recording transactions.

Research and Development

Research and development costs are expensed as incurred. These costs consist primarily of salaries and other personnel-related expenses, including associated stock-based compensation, facility-related expenses, depreciation of facilities and equipment, lab consumables and services performed by clinical research organizations, research institutions and other outside service providers.

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation and amortization of property and equipment are calculated using the straight-line method over the estimated useful lives of the assets, generally three to five years. Assets under capital lease and leasehold improvements are amortized over the lesser of their estimated useful lives or the term of the related lease. Maintenance and repairs are charged to operations as incurred. All equipment was determined to be held for sale in May 2013 and accordingly no further depreciation was recorded after that determination. Equipment categorized as held for sale on the balance sheet during the year and subsequently sold had a net book value of $0.5 million. All equipment other than computers retained for data storage was sold as of June 30, 2013 and the carrying value of equipment was reduced to zero upon completion of the sale.

Valuation of Long-Lived Assets, Prepaids and Other Assets

Long-lived assets to be held and used are reviewed for impairment when events or changes in circumstances indicate the carrying amount of an asset may not be recoverable, or its estimated useful life has changed significantly. When an asset's expected future undiscounted cash flows are less than its carrying value, an impairment loss is recognized and the asset is written down to its estimated value. Long-lived assets to be disposed of are reported at the lower of the carrying amount of fair value less cost to dispose. There were no indicators of impairment as of December 31, 2012. 56

Segment Information

We operate in one business segment with principal operations in the U.S. Collaboration revenue was from our partner headquartered in Japan. License and royalty revenue was primarily from the U.S. All of our assets reside in the U.S. Management uses one measurement of profitability and does not segregate our business for internal reporting.

Income Taxes

Shipping and Handling Costs

We acquire poly(ethylene) glycol reagent, or PEG, and API to support Takeda's manufacturing process. Shipping and handling costs incurred for PEG purchases are recorded in selling, general & administrative, or SG&A, expense in the statement of operations because they are not directly reimbursed by Takeda. Shipping and handling costs incurred for API purchases are reimbursed by Takeda and are recorded as a receivable until they are reimbursed.

Net Loss Per Common Share

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~~Basic~~We assess the impairment of long-lived assets when events or changes in circumstances indicate that the carrying value of the assets or the asset grouping may not be recoverable. Factors that we consider in deciding when to perform an impairment review include significant negative industry or economic trends, and ~~diluted~~significant ~~net~~changes ~~loss~~or ~~per~~planned ~~share~~changes isin ~~computed~~our byuse ~~dividing~~of ~~net~~the ~~loss~~assets. We measure the recoverability of assets that will continue to be used in our operations by comparing the ~~weighted-average~~carrying ~~number~~value of ~~shares~~the ofasset ~~common~~grouping ~~stock~~to ~~outstanding~~our ~~during~~estimate of the ~~period~~related total future undiscounted net cash flows. ~~Stock~~ If ~~options~~an asset grouping's carrying value is not recoverable through the related undiscounted cash flows, ~~warrants~~the asset grouping is considered to be impaired. The impairment is measured by comparing the difference between the asset grouping's carrying value and its fair value. Fair value is the price that would be received from selling an asset in an orderly transaction between market participants at the measurement date. Long-lived assets such as intangible assets and property, ~~restricted~~plant ~~stock~~and ~~units~~equipment orare ~~RSUs~~considered non-financial assets, and ~~common~~are ~~stock~~recorded ~~issuable~~at ~~pursuant~~fair value only when an impairment charge is recognized. The recall of OMONTYS was considered to be an impairment indicator for certain assets. We evaluated the ~~2006~~recoverability ~~Employee~~of ~~Stock~~our ~~Purchase~~assets ~~Plan~~and determined that certain assets were ~~not~~impaired. We ~~included~~recorded inimpairment charges for the ~~diluted~~year ~~net~~ended ~~loss~~December ~~per~~31, ~~common~~2013 ~~share~~of ~~calculation~~$4.4 ~~for~~million. ~~the~~These ~~periods~~charges ~~presented~~are ~~because~~reflected in the ~~inclusion~~statement of ~~such~~operations ~~shares~~under ~~would~~the ~~have~~caption ~~had~~"Impairment an(gain ~~antidilutive~~on ~~effect~~disposal) of prepaid expenses, fixed assets, and intangible assets.

Net Loss Per Common Share

Basic and diluted net loss per share is computed by dividing net loss by the weighted-average number of shares of common stock outstanding during the period. Stock options, warrants, unvested restricted stock units or RSUs, and common stock issuable pursuant to the 2006 Employee Stock Purchase Plan were not included in the diluted net loss per common share calculation for the periods presented because the inclusion of such shares would have had an antidilutive effect.

The computations for basic and diluted net loss per share are as follows (in thousands):

	Year ended December 31,
	2012			2011			2010
	2013			2012			2011
Numerator:
Net loss	$	(9314,~~412~~424	)	$	(6193,~~367~~412	)	$	(1461,~~075~~367	)
Denominator:
Weighted-average number of common shares used in computing basic and diluted net loss per common share	3637,~~342~~448			3336,~~288~~342			2433,~~488~~288
Basic and diluted net loss per common share	$	(20.5739	)	$	(12.8457	)	$	(01.5784	)

The following shares were excluded from the computation of diluted net loss per common share for the periods presented because including them would have an antidilutive effect (in thousands):

	Year ended December 31,
	2012	2011	2010
	2013	2012	2011
Options to purchase common stock	41,~~858~~840	4,~~262~~858	34,~~890~~262
Common stock issuable pursuant to the 2006 Employee Stock Purchase Plan	40—	4140	2941
Restricted stock units	~~297~~—	~~362~~297	~~503~~362
Warrant to purchase common stock	424	~~426~~424	426

Stock-Based Compensation

We account for equity instruments issued to employees and directors under the authoritative guidance for share-based payments.

The equity instruments we most typically grant are stock options and RSUs. Stock options are valued using the Black-Scholes valuation model while the fair value of RSUs is equivalent to the market value of the equivalent number of shares of common stock on the date of grant. The measurement of stock-based compensation is subject to periodic adjustments as the underlying equity instruments vest or do not vest as a result of employee terminations prior to ~~vest~~vesting.

We have issued stock options to ~~nonemployees~~non-employees. We account for equity instruments issued to ~~nonemployees~~non-employees in accordance with the authoritative guidance for equity-based payments to ~~nonemployees~~non-employees, using a fair value approach.

~~New Accounting Standards Recently Adopted~~57

~~Effective~~Table January 1, 2012 we adopted revised guidance related to fair value measure disclosure that increases comparability between U.S. GAAP and International Financial Reporting Standards. This guidance clarifies the application of existing fair value measurement and disclosure and changes certain principles or requirements for fair value measures and disclosure. We have expanded disclosure in our financial statements to reflect this adoption. It did not impact our financial results. Contents

~~Effective~~During ~~January 1,~~the ~~2012,~~quarter weended ~~adopted~~June ~~revised~~30, ~~guidance~~2013, ~~related~~we toterminated the ~~presentation~~Employee ofStock ~~comprehensive~~Purchase ~~income~~Plan ~~that increases comparability between U.S. GAAP~~ and ~~International~~the ~~Financial~~Restricted ~~Reporting~~Stock ~~Standards.~~Award ~~We have elected to disclose comprehensive income in a separate statement in our annual report and in a single continuous statement during interim reporting periods~~Plan.

3. Development and Commercialization Agreements with Takeda

We entered into two separate collaboration agreements with Takeda in February 2006 and June 2006 related to the co-development and co-commercialization of OMONTYS, which have been combined for accounting purposes due to their proximity of negotiation. We previously amended these arrangements in November 2011 concurrent with the settlement and license agreement, or Settlement and License Agreement, with Janssen (see further discussion below and Note 4 of Notes to Financial Statements).

66On February 23, 2013, we and Takeda announced a nationwide voluntary recall of OMONTYS as a result of post-marketing reports regarding safety concerns, including anaphylaxis. As a result of the voluntary recall of OMONTYS, all marketing activities were suspended. Effective April 1, 2013, we and Takeda entered into the Amendment to the February 2006 and June 2006 agreements to amend and restate the ongoing respective roles and responsibilities and related commitments and financial terms between the Parties, including the termination of the Collaboration and License Agreement dated as of February 13, 2006, under which we had granted Takeda a certain right and license for the development and commercialization in Japan of OMONTYS, as amended by the First Amendment, dated April 1, 2007, the Second Amendment, dated January 1, 2008 and the Third Amendment, dated November 7, 2011, as well as the related manufacturing supply, safety, quality and co-promotion agreements between the parties. The Amendment revised the economics from a profit-sharing arrangement to a milestone and royalty-based compensation structure to us effective as of April 1, 2013. The Amendment is part of our ongoing restructuring efforts resulting from the voluntary recall announced on February 23, 2013 related to OMONTYS, the suspension of U.S. marketing and promotional activities, and the ongoing investigation with the FDA.

The Amendment effectuated a transfer of regulatory responsibilities, including the OMONTYS NDA, and all manufacturing, and development responsibilities from us to Takeda. Takeda received a worldwide, exclusive royalty-bearing license under our and joint Takeda-Affymax patents to develop, manufacture and commercialize OMONTYS.

Collaboration revenue reported on our statement of operations consists of the nonrefundable upfront license fees, reimbursement for the sale of API net of costs incurred, net reimbursement of certain development and commercial expenses, revenues from product profit sharing, and milestone payments. We recognized $1.4 million, $94.4 million, and $47.7 million of collaboration revenue during the year ended December 31, 2013, 2012, and 2011, respectively. Of the $1.4 million received in 2013, $0.5 million represented reimbursement for transition personnel assisting in the transfer of regulatory responsibilities to Takeda. The amount receivable from Takeda as of December 31, 2013 and December 31, 2012 was $0.0 million and $18.4 million, respectively.

Development and Commercialization of OMONTYS in the U.S. Prior to the April 2013 Amendment

Prior to the Amendment, Takeda bore responsibility for 70% of all third-party expenses related to U.S. development and 50% of all third party expenses related to U.S. commercialization. Certain employee-related expenses supporting the commercialization of OMONTYS in the U.S. were also shared equally. In addition, costs of certain employees in clinical, regulatory and other development functions supporting any post-marketing development activities such as additional clinical trials required by the FDA as a condition of the approval of OMONTYS in March 2012 or other activities separately agreed to by the parties in the U.S. were shared equally. As part of the Amendment between us and Takeda, both Parties agreed that they will no longer share expenses related to third-party development (70/30 split) and commercialization (50/50 split) as of April 1, 2013. Any expenses incurred by either us or Takeda after April 1, 2013 shall be the responsibility of the respective party and neither Affymax nor Takeda has the right to share expenses with each other.

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~~Statements)~~affairs field force but shared marketing, account management and payor reimbursement related activities with Takeda. ~~These~~Takeda ~~arrangements~~was responsible for manufacturing and ~~amendment~~distribution ~~are~~of ~~collectively~~the ~~referred~~finished todrug asproduct to the ~~Arrangement~~customer and recorded product sales of OMONTYS. Specifically, Takeda ~~has~~had ~~the~~sole ~~right~~responsibility for handling all returns, order processing, invoicing and collection of receivables with regard to ~~terminate~~sales of OMONTYS. Takeda also had the ~~June~~rights ~~2006~~and ~~collaboration~~responsibility ~~agreement~~for establishing and modifying terms and conditions with respect to the sale of OMONTYS in ~~its~~the ~~entirety~~U.S., ~~upon~~including ~~written~~pricing ~~notice~~discounts available to ~~Affymax~~third byparty atpayers, ~~least~~price ~~six~~adjustments ~~months~~and ~~written~~other ~~notice~~allowable ~~prior~~discounts and allowances. In addition, as we and Takeda split profits 50/50 in the U.S., the Co-Promotion Agreement provided further detail relating to the ~~effective~~treatment ~~date~~of FTE expenses used to calculate eligible commercial expenses incurred by us and Takeda thereunder. Consistent with the terms of the ~~termination~~Arrangement, Takeda retained final decision making authority with respect to terms related to pricing and contracting and responsibility for distribution activities.

~~Collaboration~~Prior to the Amendment, while Takeda was responsible for the sale of OMONTYS and accordingly Takeda recorded product revenue, ~~reported~~we onand ~~our~~Takeda ~~statement~~shared equally in the net profits and losses of ~~operations~~those ~~consists~~sales of OMONTYS in the ~~nonrefundable~~U.S. In ~~upfront~~determining ~~license~~the ~~fees~~OMONTYS net profit or loss, ~~reimbursement~~OMONTYS ~~for~~product ~~the~~revenue ~~sale~~was reduced by rebates and discounts, cost of ~~API~~goods, and other gross-to-net ofadjustments ~~costs~~incurred by Takeda; royalty expense incurred by us, ~~net~~commercialization ~~reimbursement~~expenses (FTE related and out of pocket costs) incurred by both Takeda and us, and certain development ~~and~~costs ~~commercial~~associated ~~expenses,~~with ~~revenues~~post-marketing ~~from~~development ~~product~~activities ~~profit~~(FTE ~~sharing,~~related and ~~milestone~~out ~~payments~~of pocket costs) incurred by both Takeda and us. We ~~recognized~~reviewed ~~$94.4~~the ~~million~~revenue, ~~$47.7~~related ~~million,~~deductions and ~~$112.5~~expenses ~~million~~provided ofby ~~collaboration~~Takeda ~~revenue~~and ~~during~~prepared an invoice to Takeda for our portion of the ~~year~~OMONTYS ~~ended~~net ~~December 31,~~profit ~~2012,~~after ~~2011,~~factoring in applicable costs incurred by us and ~~2010,~~Takeda ~~respectively~~at the end of each quarter. The ~~amount~~profit ~~receivable~~equalization ~~from~~amount ~~Takeda~~was recognized as ofrevenue ~~December 31,~~in ~~2012~~the ~~and~~period ~~December 31,~~the ~~2011~~product ~~was~~sales ~~$18.4~~occurred ~~million~~ and ~~$6.9~~product ~~million,~~revenue ~~respectively~~was recognized by Takeda.

OnAs ~~February~~a ~~23,~~result ~~2013,~~of wethe ~~and Takeda announced a nationwide~~ voluntary recall of OMONTYS asin aFebruary ~~result~~2013, ofall ~~postmarketing~~marketing ~~reports~~activities ~~regarding~~were ~~safety concerns, including anaphylaxis~~suspended. WeAs ~~and~~part ~~Takeda~~of ~~are actively investigating~~ the ~~cause~~Amendment ofwith ~~these~~Takeda, ~~reactions~~the ~~but~~profit ~~there~~equalization ~~can~~revenue befor nothe ~~assurance~~six ~~that~~months aended ~~solution~~June ~~will~~30, be2013 ~~found. As~~was ~~a result of~~ the ~~voluntary~~final ~~recall~~profit ofequalization ~~OMONTYS,~~payment ~~all~~under ~~marketing~~the ~~activities~~Arrangement. Upon ~~have~~signing ~~been~~the ~~suspended~~Amendment ~~and~~with ~~there~~Takeda, isthe ~~significant~~economics ~~uncertainty~~of asthe tocollaboration ~~when~~changed orfrom ifa weprofit ~~will~~sharing bearrangement ~~able~~ to ~~reintroduce OMONTYS. Although we still maintain~~ a ~~license~~milestone and ~~are~~royalty-based ~~actively~~compensation ~~exploring~~structure ato ~~cause for these safety concerns~~us, weeffective doApril ~~not know when this reintroduction will occur~~1, ~~if at all~~2013.

Development and Commercialization of OMONTYS in the U.S.

Takeda bears responsibility for 70% of all third-party expenses related to U.S. development and 50% of all third party expenses related to U.S. commercialization. Certain employee-related expenses supporting the commercialization of OMONTYS in the U.S. are also shared equally. In addition, costs of certain employees in clinical, regulatory and other development functions supporting any post-marketing development activities such as additional clinical trials required by the FDA as a condition of the approval of OMONTYS in March 2012 or other activities separately agreed to by the parties in the U.S. are shared equally.

In February 2012, as contemplated under the Arrangement, we and Takeda entered into a Co-Promotion Agreement to further specify and formalize terms and conditions relating to the joint U.S. commercialization activities for OMONTYS including a corporate governance structure and division of roles and responsibilities between us and Takeda, including deployment of resources. We are responsible for deployment of the sales force and the medical affairs field force but share marketing, account management and payor reimbursement related activities with Takeda. Takeda is responsible for manufacturing and distribution of the finished drug product to the customer and records product sales of OMONTYS. Specifically, Takeda has sole responsibility for handling all returns, order processing, invoicing and collection of receivables with regard to sales of OMONTYS. Takeda also has the rights and responsibility for establishing and modifying terms and conditions with respect to the sale of OMONTYS in the U.S., including pricing discounts available to third party payers, price adjustments and other allowable discounts and allowances. In addition, as we and Takeda split profits 50/50 in the U.S., the Co-Promotion Agreement provides further detail relating to the treatment of FTE expenses used to calculate eligible commercial expenses incurred by us and Takeda thereunder. Consistent with the terms of the Arrangement, Takeda retains final decision making authority with respect to terms related to pricing and contracting and responsibility for distribution activities.

While Takeda is responsible for the sale of OMONTYS and accordingly Takeda records product revenue, we and Takeda share equally in the net profits and losses of those sales of OMONTYS in the United States. In determining the OMONTYS net profit or loss, OMONTYS product revenue is reduced by rebates and discounts, cost of goods, and other gross-to-net adjustments incurred by Takeda; royalty expense incurred by us, commercialization expenses (FTE related and out of pocket costs) incurred by both Takeda and us, and certain development costs associated with post-marketing development activities (FTE related and out of pocket costs) incurred by both Takeda and us. We review the revenue, related deductions and expenses provided by Takeda and prepare an invoice to Takeda for our portion of the OMONTYS net profit after factoring in applicable costs incurred by us and Takeda at the end of each quarter. The profit equalization amount is recognized as revenue in the period the product sales occur and product revenue is recognized by Takeda.

As a result of the voluntary recall of OMONTYS in February 2013, all marketing activities have been suspended and there is significant uncertainty as to when or if we will be able to reintroduce OMONTYS. Although we still maintain a license and are actively exploring a cause for these safety concerns, we do not know when this reintroduction will occur, if at all.

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Development and Commercialization of OMONTYS outside of the U.S.

In February 2006, we granted an exclusive license to Takeda for development and commercialization of OMONTYS in Japan. In December 2011, Takeda announced that it had decided not to commercialize OMONTYS in Japan. We and Takeda have explored other options for the commercialization rights for OMONTYS in the Japanese market, including potentially licensing it to a third party. If Takeda or its licensee is successful in clinical development and regulatory milestones, we are eligible to receive contingent payments from Takeda which aggregate up to $33.0 million relating to the Japan renal program and $5 million for a third indication that neither we or Takeda is pursuing. Per the terms of the Amendment, the Japan agreement was terminated.

In June 2006, Takeda subsequently received an exclusive license to develop and commercialize the product outside of the U.S. Takeda bears all costs for product clinical development in support of regulatory approval for all territories outside the U.S. and will pay us a variable royalty based on annual net sales of the product outside the U.S. In February 2012, Takeda announced the acceptance for assessment from the Eupopean Medicines Agency or EMA of a Marketing Authorization Application or MAA for OMONTYS for the treatment of symptomatic anemia associated with chronic kidney disease in adult patients on dialysis. ~~The~~As ~~application~~a isresult ~~currently~~of ~~under~~the ~~review~~recall byof ~~that~~OMONTYS, ~~agency~~the MAA application has been withdrawn.

Launch Allowance

As noted above, Takeda ~~bears~~bore responsibility for 50% of all third party expenses related to the commercialization of OMONTYS in the U.S. Takeda also provided a launch allowance to help fund the initial costs associated with preparing to launch under which it committed to fund the first $20.0 million of U.S. commercial expenses incurred in total by us and Takeda. Amounts received under the launch allowance are non-refundable; under the Amendment, however, Takeda is entitled to deduct up to 8% ~~of net sales~~ from ~~the~~any ~~profit~~future ~~equalization~~payments ~~revenue,~~made ~~which~~to ~~would~~us ~~have~~under ~~otherwise~~the ~~been~~royalty ~~due~~or tomilestone usprovisions ~~each period~~ until they have recouped an amount equal to $11.0 million ($10.0 million plus a $1.0 million fixed amount that represents interest). ~~During the year ended December 31, 2012, $2.8 million was deducted by Takeda from profit equalization revenue under this arrangement.~~ As of December 31, ~~2012~~2013, our liability balance under the launch allowance is $78.92 million.

Due to voluntary recall of OMONTYS in February 2013, all marketing activities have been suspended and there is no certainty as to when those activities will restart. The launch allowance will remain as a liability until we can determine, if at all, the timing of when that liability will be extinguished or if the collaboration is terminated. If our collaboration with Takeda is terminated prior to Takeda's recoupment of the balance, there is no obligation that we repay these amounts.

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all, the timing of when that liability will be extinguished or if the collaboration is terminated. If our collaboration with Takeda is terminated prior to Takeda's recoupment of the balance, there is no obligation that we repay these amounts.

Milestones

During 2012 we earned the following milestone payments from Takeda, a $50.0 million milestone upon FDA approval of OMONTYS in the dialysis indication, a $5.0 million milestone upon acceptance for review of the MAA, filing for OMONTYS by the EMA, and a $3.0 million and $2.253 million milestone related to an amendment to the Arrangement or the November 2011 Amendment, described below. As of December 31, 2012, we are eligible to receive a total of $357.0 million in additional milestone payments, which include the milestones below. Upon the successful achievement of as yet unmet clinical development and regulatory milestones, we are eligible to receive from Takeda an additional aggregate amount of $95.0 million of substantive milestone payments relating to the renal program, of which $20.0 million is associated with the first approval in either pre-dialysis or dialysis indication in the first major European Union or E.U. country. The remaining $75.0 million in payments for the renal program under the worldwide agreement are aggregated as they do not have estimated dates of achievement in the near- or medium-term. In addition, we are eligible to receive from Takeda an aggregate of $112.0 million of substantive milestone payments related to oncology for unmet clinical development and regulatory milestones and only a portion of these payments relate to the U.S. The collaboration is not pursuing the oncology program; accordingly future payment of this aggregate amount is unlikely. In addition, we are eligible to receive up to $150.0 million of sales-based milestones of $10.0 million, $20.0 million, $30.0 million, $40.0 million and $50.0 million for worldwide net sales, excluding Japan, reached and recorded by Takeda during a fiscal year of the arrangement of $0.5 billion, $1.0 billion, $1.5 billion, $2.0 billion and $3.0 billion, respectively. We are also entitled to certain milestone payments related to the Settlement and License Agreement with Janssen (see further discussion below and in Note 4 of Notes to Financial Statements). Although we are eligible to receive future milestones from Takeda, timing and amounts of future milestone payments, if any, are extremely uncertain due to the recall.

As a result of the Amendment, Takeda assumed full responsibility for OMONTYS, including the ongoing recall and investigation of OMONTYS as well as any subsequent decisions as to whether the product may be subject to reintroduction if Takeda is able to complete the investigation and address the safety concerns to the satisfaction of the FDA. We provided transition support to Takeda through April 30, 2013. After April 30, 2013 we have no performance obligations under our agreement with Takeda. If Takeda decides to reintroduce OMONTYS, all of which is highly uncertain, we are eligible to receive royalties and (i) potential contingent payments in the form of commercial milestone payments totaling up to $180.0 million, which consist of the following: (a) $10.0 million is payable upon the first commercial sale after reintroduction of OMONTYS in the U.S.: (b) $10.0 million and another $10.0 million relates to U.S. sales-based milestones, and (c) $150.0 million relates to sales-based milestones outside of the U.S. as disclosed below but now including Japan as a result of the Amendment and (ii) a potential development milestone payment of $5.0 million payable either upon regulatory approval in the E.U. or Japan. The royalties are tiered in the range of 13% to 17% with respect to net sales in the U.S. and in the range of 13% to 24% depending on the level of net sales by Takeda worldwide outside of the U.S. The $150.0 million of sales-based milestones consists of milestones of $10.0 million, $20.0 million, $30.0 million, $40.0 million and $50.0 million for worldwide net sales reached and recorded by Takeda during a fiscal year of the arrangement of $0.5 billion, $1.0 billion, $1.5 billion, $2.0 billion and $3.0 billion, respectively. Although we are eligible to receive future milestones from Takeda, timing and amounts of future milestone payments, if any, are highly uncertain due to the recall.

API Supply Agreement

In November 2011, as contemplated under the Arrangement, we and Takeda executed a Commercial API Supply Agreement. Under the terms of the API Supply Agreement, we ~~are~~were responsible for the manufacture and supply of all quantities of API to be used in the development and commercialization of OMONTYS worldwide. Takeda ~~reimburses~~reimbursed us for our cost of API plus 20%. Takeda was responsible for the fill and finish steps in the manufacture of OMONTYS worldwide under the Arrangement. As of December 31, 2012 we had a balance of $17.8 million recorded as an Advance from Takeda which was related to deferred revenue on API shipped to Takeda. As a result of the recall and the impairment charges recorded on the OMONTYS inventory during 2012, the remaining balance of deferred revenue was reversed as of June 30, 2013.

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API plus 20%. Takeda remains responsible for the fill and finish steps in the manufacture of OMONTYS worldwide under the Arrangement. Under the terms of the Commercial API Supply Agreement, Takeda agreed to pay an aggregate of $10.8 million in deposits for commercial API manufactured by us, all of which had been received as of December 31, 2012. In addition, during the year ended December 31, 2012, Takeda also paid us another deposit of $0.5 million to be applied to future purchases of commercial API. Through December 31, 2012, we have received $11.3 million and shipped $10.8 million of API that reduced the deposit balance to $0.5 million. Any amounts received from Takeda under the API Supply Agreement in excess of book value of the API were originally recorded as deferred revenue in the account named Deposit from Takeda until the related product had been sold through to the end customer by Takeda. For the year ended December 31, 2012, we recognized revenue of $0.9 million related to API. $2.3 million of API was shipped to Takeda prior to December 31, 2012 and is pending acceptance.

Given the uncertainty of the recall and the return of product containing API that followed the recall, we have recharacterized our deferred revenue as an Advance from Takeda, which is reflected as a current liability in our December 31, 2012 financial statements. Given the significant uncertainty in future revenues at this time, we cannot predict if or when OMONTYS sales will recommence.

Impairment of Inventory and Firm Purchase Commitments

WePrior ~~initiate~~to the voluntary recall, we initiated orders for API with our CMOs based on forecasts from Takeda, which ~~are~~were based on expected demand for OMONTYS. Orders generally ~~have~~had commenced once there was a contractual commitment for the API from Takeda. AsIn ofthe ~~December~~quarter ~~31,~~ended ~~2012~~June 30, 2013 we ~~have~~settled ~~future~~these ~~purchase~~obligations ~~commitments~~for ~~amounting~~less tothan ~~$34.6~~the ~~million. These~~contractual ~~future commitments are comprised of $5~~amounts.8 ~~million~~We ~~for~~made ~~firm~~a ~~purchase~~total ~~commitments~~ of ~~PEG, and the remaining~~ $2811.80 million ofin ~~manufacturing~~payments ~~obligations relate~~ to ~~API,~~settle ~~and~~our ~~were~~obligations ~~based~~to onthree ~~firm~~CMOs ~~demand forecasts from Takeda~~ and ~~therefore~~recorded ~~may~~a befavorable ~~subject~~adjustment to ~~reimbursement~~our ~~under~~operating ~~the~~results ~~API~~of ~~Supply~~$21.9 ~~Agreement with Takeda~~million.

In addition to the binding CMO purchase commitments, we also had $10.4 million in inventory and prepayments made to our CMOs on our balance sheet as of December 31, 2012. As a result of the inability to sell OMONTYS and the uncertainty of future revenues, we have written down our API inventory and prepayments for API being produced by our CMOs to a net realizable value of zero and ~~have~~ recorded ana $10.4 million impairment charge related to this writedown~~. We~~ ~~have~~during ~~also recorded a $34.6 million loss on firm purchase commitments by applying~~ the ~~same~~year ~~lower~~ended ofDecember ~~cost~~31, ~~or market approach that is used to value inventory~~2012. Of the total $45.0 million charge for impairment of inventory and loss on CMO purchase commitments recorded in 2012, we ~~have~~recorded ~~the~~a ~~right~~benefit ~~under~~of $20.3 million in the ~~Arrangement~~first toquarter ~~submit~~of 2013, primarily related to ~~Takeda~~the ~~for~~collaboration cost reimbursement ~~$18~~under the Takeda Q1 profit equalization payment.4 As ~~million~~a result of ~~such~~the ~~expenses~~fourth Amendment, Takeda assumed full responsibility for OMONTYS. ~~However~~This ~~because~~includes wethe ~~have~~ongoing ~~not~~investigation ~~presented~~of ~~such~~OMONTYS ~~amounts~~as towell ~~Takeda~~as ~~for~~any ~~reimbursement,~~subsequent ~~and~~decisions ~~such~~as ~~reimbursements~~to ~~would~~whether the product may be subject to reintroduction. Reintroduction would be possible only if Takeda's ~~approval,~~is weable ~~have~~to ~~not~~complete ~~recorded~~the ainvestigation ~~receivable~~and ~~for~~address ~~such~~the ~~amounts~~safety asconcerns ofto ~~December~~the ~~31,~~satisfaction ~~2012.~~of the FDA.

Cost of Recall

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InAs ~~the~~a ~~first~~result ~~quarter~~ of ~~2013,~~the wefourth ~~believe~~Amendment, Takeda ~~will~~assumed ~~record~~full anresponsibility ~~impairment charge~~ for ~~certain~~OMONTYS. ~~long~~This ~~lived~~includes ~~assets~~the ~~associated~~ongoing ~~with~~investigation of OMONTYS~~. Under~~ ~~the~~as ~~profit/loss~~well ~~equalization~~as weany ~~are~~subsequent ~~responsible~~decisions ~~for~~as ~~half~~to ofwhether ~~these~~the ~~charges~~product may be subject to reintroduction. We ~~estimate~~Reintroduction ~~our~~would ~~exposure~~be ~~related~~possible toonly ~~this~~if ~~impairment~~Takeda is able to becomplete ~~approximately~~the ~~$7.0~~investigation ~~million. This~~and ~~amount~~address ~~has~~the ~~not~~safety ~~been~~concerns ~~accrued~~to asthe satisfaction of ~~December~~the ~~31, 2012~~FDA.

The total costs of recalling the product were primarily composed of costs to a third-party to gather, store, and return the product to Takeda, of which $1.1 million was incurred in the first quarter of 2013. Our portion of the expense was $0.6 million which we were charged as a part of the Q1 profit equalization payment in the first quarter of 2013.

Takeda capitalizes inventory costs associated with the production of OMONTYS and enters into purchase commitments for goods associated with this manufacturing. The write down or write off of such inventory and any charges for purchase commitments by Takeda was subject to the profit equalization revenue or loss calculation of the Arrangement. Takeda included inventory write down charges of $31.8 million for the cost of inventory on hand at Takeda as of March 31, 2013 in the Q1 profit equalization payment. Our portion of this write down was $15.9 million and was previously reserved for as of December 31, 2012 as a part of our Advance from Takeda liability. With respect to purchase commitments, Takeda requested reimbursement for a portion of the costs associated with Takeda's firm purchase commitment of $9.3 million with Baxter for pre-filled syringes. Our exposure was limited to the portion of the Baxter agreement that relates to the U.S. We had no liability related to the E.U. or Japan because in those countries we receive only a royalty on product sales and the collaboration profit split did not apply to operations in those countries. The amount of our exposure was $0.7 million which was included in the Q1 profit equalization payment in the first quarter of 2013.

In the first quarter of 2013, Takeda recorded an impairment charge for certain long lived assets associated with OMONTYS. Under the profit/loss equalization we were responsible for half of these charges. Our exposure related to this impairment was $6.2 million. This amount was charged to us as a part of the Q1 profit equalization payment in the first quarter of 2013.

November 2011 Amendment

In November 2011, concurrent with the execution of the Settlement and License Agreement with Janssen, we and Takeda entered into an amendment to the Arrangement. Under the terms of this amendment, Takeda ~~has~~ agreed to pay up to $6.5 million in additional milestones to us in consideration of the upfront and milestone payments we are required to make to Janssen under the Settlement and License Agreement. Approximately $5.253 million of these milestones ~~are~~were earned based on regulatory and commercial events in the U.S. and the remaining $1.253 million is tied to regulatory events in the E.U, which was eliminated as part of the Amendment. We recognized $3.0 million of these milestones in the first quarter of 2012 as it was earned as a result of FDA approval in March 2012. ~~An additional $2.25 million of these milestones was earned in July~~ ~~2012 as a result of progress on the commercial launch of OMONTYS, and recognized in the third quarter of 2012.~~

4. Contractual Arrangements

Our License, Manufacturing and Supply Agreement with Nektar

In April 2004, we entered into a License, Manufacturing and Supply Agreement with Nektar Therapeutics AL Corporation, or Nektar, under which we obtained from Nektar a worldwide, non-exclusive license, with limited rights to grant sublicenses, under certain intellectual property covering pegylation technology to manufacture, develop and commercialize OMONTYS. The license we obtained consists of a license under intellectual property owned by Nektar and a sublicense under intellectual property owned by Enzon Pharmaceuticals, Inc., or Enzon, licensed to Nektar pursuant to a cross-license agreement between Nektar, Inhale Therapeutic Systems, Inc. and Enzon.

In consideration of the license grant, we agreed to pay royalties on the sales of OMONTYS, which began with the launch of the product in the U.S. in 2012 and was suspended on February 26, 2013. We also agreed to pay base milestones plus possible additional milestones in connection with our partnering activities relating to OMONTYS or merger and acquisition activities. As of December 31, ~~2012~~2013 no further milestone obligations remain.

Contract Manufacturing Organization (CMO) Settlements

We initiated orders for API with our CMOs based on forecasts from Takeda, which were based on expected demand for OMONTYS. Orders generally commenced once there was a contractual commitment for the API from Takeda. As of December 31, 2012, we had future purchase commitments amounting to $34.6 million. These future commitments were

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comprised of $5.8 million for firm purchase commitments of PEG, and the remaining $28.8 million of manufacturing obligations relate to API, and were based on firm demand forecasts from Takeda. We paid $1.7 million in payments to our CMOs in our first quarter 2013 which reduced the accrual balance to $32.9 million.

We finalized settlement agreements with the CMOs in the second quarter of 2013 and made a total of $11.0 million in payments resulting in a favorable adjustment to our second quarter 2013 operating results of $21.9 million.

Settlement and License Agreement with Janssen

In November 2011, we entered into the Settlement and License Agreement with Janssen under which we obtained a non-exclusive license to the intellectual property in dispute, a covenant not to sue and a release of all claims associated with the arbitration and dispute. The Settlement and License Agreement also provides for the dismissal of all pending proceedings. The Settlement and License Agreement required us to make two fixed payments to Janssen, $6.0 million, which was paid in December 2011, and $2.0 million, which was paid in June 2012. Upon execution of the Settlement and License Agreement in the fourth quarter of 2011, we recorded $8.0 million of R&D expense relating to the fixed payments. The Settlement and License Agreement also required us to make a $2.5 million milestone payment to Janssen upon FDA regulatory approval of OMONTYS, and requires us to make a $2.5 million milestone payment to Janssen upon regulatory approval of OMONTYS in the first major European country. Upon FDA approval in March 2012, we capitalized $2.5 million related to the first milestone payment during the first quarter of 2012 as an other asset. The resulting asset ~~will~~was to be amortized over the expected life of the related patent family, the last-expiring patent of which expires in June 2016. This $2.5 million milestone payment was paid to Janssen in April 2012. For the year ended December 31, ~~2012~~2013, weas ~~recognized~~a ~~$0.4~~result ~~million~~ of ~~amortization expense. In~~ the ~~first~~recall, ~~quarter~~ we ~~expect~~recorded toa ~~incur~~ $2.1.9 million inimpairment ~~charges~~charge related to ~~the impairment if the remaining balance of~~ this asset, asbringing ~~a result of~~ the ~~recall. This~~asset ~~amount~~value ~~has~~to ~~not been accrued as of year-end~~zero.

In addition, Janssen will be entitled to low, single-digit royalties on sales of OMONTYS in Europe, Japan and certain other countries outside of the United States until mid-2016. This royalty payment is not reimbursable under our collaboration with Takeda.

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5. Balance Sheet Components

Property and Equipment, Net

Property and equipment consist of the following (in thousands):

	December 31,
	2012			2011
	2013			2012
Leasehold improvements	$	~~2,501~~—		$	2,~~303~~501
Equipment	~~9,794~~—			89,~~748~~794
Software	~~3,064~~—			23,~~428~~064
Construction in progress	9—			~~630~~9
	15,368			14,109
	—			15,368
Less: Accumulated depreciation and amortization	~~(12,387~~—		)	(1112,~~096~~387		)
	$	~~2,981~~—		$	32,~~013~~981

Depreciation and amortization expense for the years ended December 31, ~~2012~~2013, ~~2011~~2012, and ~~2010~~2011, was $0.7 million, $2.0 million, and $2.2 million, respectively. In addition to the expense noted above, we also incurred $1.9 million in impairment charges for the year ended December 31, 2013. In May of 2013 management committed to a plan to sell all of the Company's property and equipment. The assets were classified as held for sale and depreciation expense was recorded through May 15, 2013. The assets were sold in June of 2013 for $21.2 million. The book value of the assets sold was $0.5 million after the impairment charge and a gain of $0.7 million was recorded in the year ended December 31, ~~respectively~~2013.

Accrued Liabilities

Accrued liabilities consist of the following (in thousands):

	December 31,
	2012		2011
Accrued potential losses related to firm purchase commitments (1)	$	34,599	$	—
Compensation-related expenses	12,837		7,971
SG&A related costs (2)	3,633		1,228
R&D related costs	830		1,659
Janssen Biotech installment payment accrual	—		2,000
Other	623		1,141
	$	52,522	$	13,999

(1) See Note 3 of Notes to Financial Statements.

(2) Includes accruals relating to FDA fee, commercial and medical affairs, IT related and other miscellaneous accruals.

6. Investments

The following is a summary of our available-for-sale marketable securities (in thousands):

	As of December 31, 2012
	Cost		GrossUnrealizedGains		GrossUnrealizedLosses			Other-ThanTemporaryImpairment		Fair Value
Short-term investments:
Certificates of deposit	$	1,300	$	—	$	—		$	—	$	1,300
Corporate debt securities	8,416		1		—			—		8,417
Total short-term investments	$	9,716	$	1	$	—		$	—	$	9,717
Long-term investments:
Corporate debt securities	$	2,326	$	—	$	(3	)	$	—	$	2,323
Total long-term investments	$	2,326	$	—	$	(3	)	$	—	$	2,323

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	As of December 31, 2011
	December 31,
	Cost		GrossUnrealizedGains		GrossUnrealizedLosses			Other-ThanTemporaryImpairment		Fair Value
	2013		2012
Short-term investments:
Accrued potential losses related to firm purchase commitments	$	—	$	34,599
Certificates of deposit	$	2,241	$	—	$	—		$	—	$	2,241
Restructuring accrual	315		—
Government agency securities	41,906		23		(5		)	—		41,924
Compensation-related expenses	—		12,837
Total short-term investments	$	44,147	$	23	$	(5	)	$	—	$	44,165
SG&A related costs	266		3,633
R&D related costs	—		830
Other	—		623
	$	581	$	52,522

~~The investments mature between January 2013 and July 2014~~6. ~~No other-than-temporary impairments were identified for the investment securities held by us as of December 31, 2012.~~ Investments

We held no investments as of December 31, 2013 and there were no realized gains or losses on investments during the years ended December 31, 2013, 2012, or 2011. A summary of our investments outstanding as of December 31, 2012 is as follows (in thousands):



	As of December 31, 2012
	Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Short-term investments:
Certificates of deposit	$	1,300	$	—	$	—		$	1,300
Corporate debt securities	8,416		1		—			8,417
Total short-term investments	$	9,716	$	1	$	—		$	9,717

Long-term investments:
Corporate debt securities	$	2,326	$	—	$	(3	)	$	2,323
Total long-term investments	$	2,326	$	—	$	(3	)	$	2,323

7. Fair Value Measurements

We measure certain financial assets and liabilities at fair value on a recurring basis, including cash equivalents and available for sale securities. The fair value of these assets was determined based on a three-tier hierarchy under the authoritative guidance for fair value measurements and disclosures that prioritizes the inputs used in measuring fair value as follows:


•	Level 1 — observable inputs such as quoted prices in active markets.


•	Level 2 — inputs other than quoted prices in active markets that are observable either directly or indirectly through corroboration with observable market data.


•	Level 3 — unobservable inputs in which there is little or no market data, which would require us to develop our own assumptions.

The types of investments that are generally classified within Level 1 of the fair value hierarchy include money market securities. The valuation technique we used to measure fair value of our Level 1 money market securities is a market approach, using prices and other relevant information generated by market transactions involving identical securities. The types of investments that are generally classified within Level 2 of the fair value hierarchy include corporate securities, certificates of deposits and U.S. government securities. The valuation technique we used to measure fair value of our Level 2 investments is a market approach, under which we review trading activity and pricing for these investments as of the measurement date. When sufficient quoted pricing for identical investments was not available, we used market pricing and other observable market inputs for similar investments obtained from various third party data providers. These inputs represent quoted prices for similar investments in active markets or these inputs have been derived from observable market data.

Financial instruments that are not recorded at fair value are measured at fair value on a quarterly basis for disclosure purposes. The fair value of the notes payable are based on the present value of expected future cash flows, assumptions about current interest rates and the creditworthiness of Affymax. Market risk associated with our fixed rate debt relates to the potential reduction in fair value. The carrying amounts of our notes payable approximates fair value. 63

The carrying amounts of certain financial instruments, such as cash equivalents, accounts receivable, accounts payable and accrued liabilities, approximates fair value due to their relatively short maturities, and low market interest rates if applicable.

The following table presents our investments measured at fair value on a recurring basis classified by the fair value measurements and disclosures valuation hierarchy (in thousands):

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deposits and U.S. government securities. The valuation technique we used to measure fair value of our Level 2 investments is a market approach, under which we review trading activity and pricing for these investments as of the measurement date. When sufficient quoted pricing for identical investments was not available, we used market pricing and other observable market inputs for similar investments obtained from various third party data providers. These inputs represent quoted prices for similar investments in active markets or these inputs have been derived from observable market data.

The carrying amount of certain financial instruments, such as cash equivalents, accounts receivable, accounts payable and accrued liabilities, approximates fair value due to their relatively short maturities, and low market interest rates if applicable.

We held no assets or liabilities as of December 31, 2013 which were remeasured to fair value on a recurring basis.

The following table presents as of December 31, 2012 our investments measured at fair value on a recurring basis classified by the fair value measurements and disclosures valuation hierarchy (in thousands):



	As of December 31, 2012
			Fair Value Measurements Using
	Total		Level 1		Level 2		Level 3
Money market funds	$	45,999	$	45,999	$	—	$	—
Short-term investments:
Certificates of deposit	$	1,300	$	—	$	1,300	$	—
Corporate debt securities	8,417		—		8,417		—
Total short-term investments	$	9,717	$	—	$	9,717	$	—

Long term investments:
Corporate debt securities	$	2,323	$	—	$	2,323	$	—
Total long-term investments	$	2,323	$	—	$	2,323	$	—

	As of December 31, 2011
			Fair Value Measurements Using
	Total		Level 1		Level 2		Level 3
Money market funds	$	45,244	$	44,248	$	996	$	—
Short-term investments:
Certificates of deposit	$	2,241	$	—	$	2,241	$	—
Government agency securities	41,924		—		41,924		—
Total short-term investments	$	44,165	$	—	$	44,165	$	—

In conjunction with the product recall and related restructuring activities, management evaluated our property and equipment and committed to a plan to sell all non-essential equipment. Equipment and leasehold improvements were categorized as held for sale in May 2013 and sold in June 2013. No equipment or other fixed assets remain on the balance sheet at December 31, 2013.

8. Loan and Security Agreement

In March 2012, we entered into hea loan and security agreement, or the Loan Agreement, with Oxford Finance LLC and Silicon Valley Bank, or, collectively, the Lenders, under which we ~~may~~borrowed ~~borrow up to a total of~~ $3010.0 million ~~in two tranches~~.

~~The first tranche of $10.0 million was borrowed in March 2012.~~ ~~The~~On ~~second~~April ~~tranche~~3, of2013, ~~$20.0~~we ~~million~~entered ~~was~~into ~~available~~a ~~for~~Letter ~~drawdown~~Agreement, ~~until~~under ~~March~~which ~~31,~~(i) ~~2013;~~we ~~however,~~paid itall ~~may~~amounts nodue ~~longer~~and beowing ~~available~~so ~~due~~as to discharge our ~~recent~~obligations ~~recall~~thereunder ofwhich ~~OMONTYS~~totaled $9. ~~The~~8 ~~interest~~million ~~rate~~including ~~for~~remaining ~~the~~principal, ~~first~~interest, ~~tranche~~final ispayment ~~fixed~~and ~~upon~~prepayment ~~drawdown~~fees, at(ii) awe ~~per~~waived ~~annum~~any ~~rate~~rights ~~equal~~ to ~~the~~seek ~~greater~~additional ofcredit ~~8.95%~~extensions or ~~8.57%~~unfunded ~~plus~~commitments under the ~~then~~Loan ~~effective~~Agreement, ~~U.S.~~and ~~Treasury~~(iii) ~~note~~the ~~yield~~security tointerest ~~maturity~~granted ~~for~~to aLenders 36relating ~~month~~to ~~term~~substantially ~~but~~all inof ~~any~~our ~~event~~assets, ~~not~~other ~~less~~ than ~~thirty-eight~~our ~~basis~~intellectual ~~points~~property, (0was terminated.~~38)%. The~~ ~~interest~~As ~~rate~~of ~~related~~December to31, ~~the~~2013 ~~drawdown~~we ofhad ~~the~~no ~~first~~remaining ~~tranche~~notes ispayable 9outstanding.~~11%.~~

Payments under the Loan Agreement for the first tranche are interest-only through February 1, 2013, followed by equal monthly payments of principal and interest through the scheduled maturity date on July 1, 2015. In addition to the monthly principal and interest payments, a final payment equal to 5% of the aggregate amount drawn, or $0.5 million for the first tranche, will be due on the earliest to occur of (1) the last amortized payment, (2) the acceleration of the loan or (3) prepayments of the loan, as specified in the Loan Agreement.64

Our obligations under the Loan Agreement are secured by a first priority security interest in substantially all of our assets, other than our intellectual property. We have also agreed not to pledge or otherwise encumber our intellectual property assets, except for permitted licenses, as defined in the Loan Agreement.

We have paid the Lenders a facility fee of $150,000. In addition, if we repay all or a portion of the first tranche prior to maturity, we will pay the Lenders a prepayment fee, based on a percentage of the then outstanding principal balance, equal to: 5.00% if the prepayment occurs prior to or on the first anniversary of the respective funding date, 4.00% if the prepayment occurs after the first anniversary of the respective funding date but prior to or on the second anniversary of the respective funding date, or 2.00% if the prepayment occurs after the second anniversary of the respective funding date.

To secure our performance of our obligations under this loan and security agreement, we granted a security interest in substantially all of our assets, other than intellectual property assets, to the lenders. Our failure to comply with the terms of the

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loan and security agreement, the occurrence of a material impairment in our prospect of repayment or in the perfection or priority of the lender’s lien on our assets, as determined by the lenders, or the occurrence of certain other specified events could result in an event of default that, if not cured or waived, could result in the acceleration of all or a substantial portion of our debt, potential foreclosure on our assets, and other adverse results.

The Loan Agreement includes customary affirmative and negative covenants, but does not include any covenants to attain or maintain certain financial metrics or thresholds. The covenants include required financial reporting, requirement to maintain inventory in good and marketable conditions, limitations on certain dispositions of assets, limitations on the incurrence of additional debt, limitations on change in business purpose, merge or consolidate, or encumbrance of assets without prior written consent of the Lenders. The Loan Agreement also includes customary events of default, including payment defaults; breaches of covenants following any applicable cure period, failure to deliver financial statements and reports to the lender on a timely basis, failure to file all required tax returns on a timely basis, failure to maintain insurance on collateral, and other routine and customary requirements under a loan agreement; and a material adverse change which is defined as follows: (a) a material impairment in the perfection or priority of Lenders’ security interest or in the value of the collateral; (b) a material adverse change in our business, operations or financial condition (or otherwise); or (c) a material impairment of the prospect of repayment of any portion of the loans. Upon the occurrence of an event of default and following any applicable cure periods, a default increase in the interest rate by an additional 500 basis points (5.0)% may be applied to the outstanding loan balances, and the Lenders may declare all outstanding obligations immediately due and payable and take such other actions as set forth in the Loan Agreement.

Since we suspended the marketing activities of OMONTYS and voluntarily recalled OMONTYS, we have classified all of our loan balance as a current liability and treated it as callable. Events of default under the Loan Agreement, provide the Lenders with various rights, including the right to require immediate repayment of the outstanding principal plus accrued and unpaid interest through the prepayment date, the final payment of $0.5 million and the prepayment fee of $0.5 million. We have not received a notice of default. If we receive a notice of default from the Lenders, in addition to repaying the outstanding balance of our loan we will also accrue the remaining final interest charge and the full amount of the final payment and the prepayment fee.

In connection with the Loan Agreement, we issued the Lenders warrants to purchase 132,855 shares of our common stock, or the Warrants, at an exercise price of $11.855 per share. Each Warrant may be exercised on a cashless basis in whole or in part. The exercise period of the Warrants will terminate on the earlier of seven years from March 26, 2012, the issuance date or the closing of certain merger or consolidation transactions in which the consideration is cash or stock of a publicly traded acquiror, or a combination thereof. Using the Black Scholes valuation model, we estimated the fair value of these Warrants to be approximately $1.4 million. The following assumptions were used to estimate the fair value: expected volatility of 83.4%, risk-free interest rate of 1.65%, and expected term of seven years. These Warrants are considered to be costs incurred as part of the loan and have been recorded as a debt discount, which is offset against the loan, and is amortized over the term life of Loan Agreement based on the effective interest method to interest expense. In September 2012, SVB Financial Group, parent of Silicon Valley Bank, exercised its Warrant for a net exercise and issuance of 23,453 shares of our common stock. In October 2012, Oxford Finance LLC exercised the remaining Warrants for a net exercise and issuance of 36,660 shares of our common stock. Both of these Warrants were net exercised on a cashless basis.

Our future minimum principal payments under the Loan Agreement as of December 31, 2012 are as follows (in thousands):

2013	$	3,730
2014	4,084
2015	2,186
Total minimum principal payments	10,000
Less debt discount, net of amortization	(1,156		)
Balance at December 31, 2012	$	8,844

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9. Commitments and Contingencies

Operating Leases

WeIn ~~rent~~June ~~our~~2013 ~~office~~we ~~facilities~~moved ~~and~~our ~~certain~~remaining ~~equipment~~four ~~under~~employees ~~noncancelable~~into ~~operating~~offices ~~leases~~in Cupertino, ~~which~~California ~~expire~~and atvacated ~~various~~all ~~dates~~of ~~through~~our ~~September~~facilities ~~2014. Under~~in ~~the~~Palo ~~terms of the leases~~Alto, weCalifornia. ~~are~~The ~~responsible~~lease ~~for~~expires ~~certain~~in ~~taxes,~~July ~~insurance and maintenance expenses~~2014.

InRent ~~March~~expense ~~2012,~~for wethe ~~entered~~years ~~into~~ended aDecember 31, ~~sublease agreement with a third party to sublease a portion of one of our Palo Alto buildings. The sublease began on May 1~~2013, 2012, and ~~will~~2011 ~~end~~was on$1.8 ~~August 31~~million, ~~2014. Under the agreement we will receive future minimum payments of~~ $03.46 million and $0.3.2 million, inrespectively. We ~~2013~~recognize ~~and~~rent ~~2014,~~expense ~~respectively,~~on ~~which~~a ~~offsets~~straight-line ~~the~~basis ~~rent~~over ~~payments~~the ~~noted~~lease ~~below~~period.

~~Rent~~Future ~~expense~~minimum ~~for~~payments ~~the~~under ~~years~~non-cancelable ~~ended~~lease obligations as of December 31, ~~2012,~~2013 ~~2011,~~are ~~and~~as ~~2010~~follows ~~was~~(in ~~$3.6 million, $3.2 million and $2.8 million, respectively. We recognize rent expense on a straight-line basis over the lease period.~~thousands):

Future minimum payments under noncancelable lease obligations as of December 31, 2012 are as follows (in thousands):



2014	23
Total minimum lease payments	$	23

2013	$	4,229
2014	3,246
2015	20
Total minimum lease payments	$	7,495

Legal Proceedings

On ~~March~~February 1927, 2013, a ~~derivative~~securities ~~lawsuit~~class action complaint was filed ~~purportedly~~in onthe ~~behalf~~United ofStates District Court for the ~~Company~~Northern inDistrict of California, ~~Superior~~naming ~~Court~~as ~~for~~defendants the ~~County~~Company, certain of ~~Santa~~its ~~Clara~~officers, Takeda Pharmaceutical Company Limited, Takeda Pharmaceuticals U.S.A., Inc. and Takeda Global Research & Development Center, Inc. A second complaint naming ~~certain~~the same defendants was filed on March 6, 2013. On May 2, 2013, the securities class action complaint that was filed on February 27, 2013 was voluntarily dismissed by the plaintiff. On May 21, 2013, the Court appointed a lead plaintiff in the remaining securities class action complaint that had been filed on March 6, 2013. On July 22, 2013, a consolidated amended class action complaint was filed on behalf of ~~our~~purported ~~officers~~stockholders ~~and~~of ~~directors~~the Company, naming as defendants the Company and certain of its former officers. The ~~lawsuit~~consolidated amended complaint alleges ~~that~~violations of Section 10(b) and 20(a) of the ~~certain~~Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder, in connection with allegedly false and misleading statements made by the defendants regarding OMONTYS, the Company's ~~officers~~business practices, financial projections and ~~directors~~other ~~breached~~disclosures ~~their~~between ~~fiduciary~~August ~~duties~~8, ~~related~~2012 toand February 22, 2013, or the ~~clinical~~Class ~~trials~~Period. The ~~for~~plaintiff ~~OMONTYS~~seeks ~~and~~to ~~for~~represent ~~representations~~a ~~regarding~~class comprised of purchasers of the Company's ~~business~~common ~~health~~stock ~~which~~during ~~was~~the ~~tied~~Class Period and seeks damages, costs and expenses and such other relief as determined by the Court. On September 20, 2013, the Company and the individual defendants (collectively, “Defendants”) filed a motion to dismiss the ~~success~~consolidated amended complaint. On November 19, 2013, the plaintiff filed her opposition to the motion to dismiss and on December 19, 2013, Defendants filed their reply in support of ~~OMONTYS~~their motion to dismiss. The ~~lawsuits~~hearing ~~also~~on ~~asserts~~the ~~claims~~motion ~~for~~to ~~unjust~~dismiss ~~enrichment~~occurred on January 15, 2014. On January 21, 2014, the Court issued its order granting the motion to dismiss regarding violations of Section 20(a) against all Defendants and ~~corporate~~it ~~waste~~granted the motion to dismiss in part, denying the motion to dismiss in part, and providing plaintiffs with an opportunity to amend the complaint. On February 18, 2014, the Court, pursuant to a stipulation by the parties, stayed the litigation for ninety days to allow the parties to conduct settlement discussions.

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defendants (the “Federal Derivative Action”). The lawsuit’s allegations are substantially similar to the allegations in the State Court Derivative Action. On October 21, 2013, the Court ordered a stay in the Federal Derivative Action pending the outcome of the motion to dismiss in the securities class action. Subsequent to the order regarding the motion to dismiss in the securities class action, on January 31, 2014, the Court ordered that the Federal Derivative Action be stayed until resolution of the securities class action.

Additional complaints may be filed against us and our directors and officers related to our recall of OMONTYS.

Product Liability Litigation

Additionally, in light of the recall, a product liability claim could potentially arise, although no claim has been filed to date.

We assess litigation to determine if an unfavorable outcome would lead to a probable loss or reasonable possible loss, which could be estimated. We accrue for losses that are both probable and reasonably estimable. If the estimate of a probable loss is a range and no amount within the range is more likely, we accrue the minimum amount of the range. In the cases where we believe that a reasonable possible loss exists, we disclose the facts and circumstances of the litigation, including an estimable range, if possible. Substantially all of these contingencies are subject to significant uncertainties and, therefore, determining the likelihood of a loss and/or the measurement of any loss can be complex. Consequently, we are unable to estimate the range of reasonable possible loss. Accordingly, no loss accrual has been established for the above. While it is not possible to accurately predict or determine the eventual outcome of these matters, an adverse determination in one or more of these matters currently pending could have a material adverse effect on our financial condition, results of operations or cash flows.

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10. Stockholder's Equity

Preferred Stock

Our Certificate of Incorporation, as amended and restated in December 2006, designates and authorizes 10,000,000 shares of $0.001 par value preferred stock, none of which were issued and outstanding as of December 31, ~~2012~~2013 and ~~2011~~2012. The rights, preferences and privileges of any preferred stock to be issued pursuant to our current Certificate of Incorporation, as amended and restated, have yet to be established.

No dividends on preferred stock have been declared since inception through December 31, ~~2012~~2013.

Common Stock

Our Certificate of Incorporation authorizes us to issue 100,000,000 shares of $0.001 par value common stock. As of December 31, ~~2012~~2013, and ~~2011~~2012, respectively we had 37,~~369~~490,~~717~~095 and 3537,~~733~~369,~~181~~717 shares of common stock issued and outstanding.

No dividends on common stock have been declared since inception through December 31, ~~2012~~2013.

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Warrants

InWarrants ~~connection~~to ~~with~~purchase ~~the~~an ~~Loan~~aggregate ~~Agreement,~~of ~~in March 2012~~423,971 ~~we issued the Lenders warrants to purchase 132,855~~ shares of ~~our~~ common stock, ~~or the Warrants,~~ at an exercise price of $1116.~~855~~78 per share~~. In September 2012~~, ~~SVB~~were ~~Financial~~issued ~~Group, the parent of Silicon Valley Bank, exercised its Warrant for a net exercise of 23,453 shares of our common stock and subsequently sold these shares~~ in ~~December~~March ~~2012. In October 2012~~2009, ~~Oxford~~which ~~Finance~~was ~~LLC~~related ~~exercised~~to ~~the remaining Warrants for~~ a ~~net~~private ~~exercise of 36,660 shares of our common stock~~placement. ~~Both~~The ofwarrants ~~these~~expired ~~Warrants were net exercised~~ on aMarch ~~cashless~~2, ~~basis~~2014.

In addition, warrants to purchase an aggregate of 423,971 shares of common stock, at an exercise price of $16.78 per share, were issued in March 2009, which was related to a private placement. The warrants are exercisable immediately and expire in March 2014.

Significant Equity Transactions

In September 2012, our amended agreement with Azimuth Opportunity Ltd., or Azimuth, dated as of September 25, 2009 and amended in September 2010, expired. The agreement provided that, upon the terms and subject to the conditions set forth in the purchase agreement, Azimuth was committed to purchase up to $60.0 million worth of shares of our common stock over the 24-month term of the purchase agreement, which was available to be drawn upon beginning January 2010. The Amendment extends the term of the equity facility to September 2012. No equity was issued in 2012 or 2011 under this agreement.

In October 2010, we sold 999,061 shares of common stock to Azimuth under the Common Stock Purchase Agreement for an aggregate purchase price of $5.0 million. Our net proceeds from the sale of these shares was $4.9 million after deducting our offering expenses.

In March 2011, we completed a public offering of 9,745,762 shares of our common stock, at $5.90 per share. We received net proceeds of approximately $53.6 million, after deducting underwriting discounts and commissions and offering expenses.

Equity Incentive Plans

2001 Stock Option/Stock Issuance Plan

In September 2001, we adopted the 2001 Stock Option/Stock Issuance Plan or the 2001 Plan. The 2001 Plan provides for both the granting of stock options and issuing shares of stock to our employees and consultants. Stock options granted under the 2001 Plan may be either incentive stock options or nonqualified stock options. Incentive stock options or ISOs, may be granted only to our employees. Nonqualified stock options or NSOs, may be granted to our employees, directors and consultants. Stock options under the 2001 Plan may be granted with a maximum life of 10 years and at prices no less than the fair market value for ISOs and 85% of the fair market value for NSOs, as determined by the Board of Directors. The exercise price of an ISO or NSO granted to an individual that holds 10% or more of our outstanding stock shall not be less than 110% of the estimated fair value of the shares on the date of grant. To date, stock options granted generally become exercisable over four years. We issue new shares of common stock upon exercise of stock options.

2006 Equity Incentive Plan

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Upon the effectiveness of our initial public offering in December 2006, we adopted the 2006 Equity Incentive Plan, which was amended and restated in June 2012, or the 2006 Plan. Shares of common stock issuable pursuant to all then outstanding stock awards granted under the 2001 Plan remained subject to the terms of the 2001 Plan and no additional stock awards were granted pursuant to the terms of the 2001 Plan upon the effective date of the 2006 Plan.

The 2006 Plan provides for both the granting of stock awards, including stock options and RSUs, to our employees, directors and consultants. Stock options granted under the 2006 Plan may be either ISOs or NSOs. ISOs may be granted only to our employees. NSOs may be granted to our employees, directors and consultants. Stock options under the 2006 Plan may be granted with a maximum life of 10 years and at prices no less than the fair market value of our common stock on the date of grant. The exercise price of an ISO granted to a 10% stockholder shall not be less than 110% of the fair market value of our common stock on the date of grant. To date, stock options granted generally become exercisable over four years and do not allow for the early exercise of options prior to vesting. The terms of the RSUs granted by us to date provide for vesting and delivery of shares of common stock generally over three years or are subject to performance based vesting upon milestones (described below). As of December 31, ~~2012~~2013, we reserved 68,~~908~~308,443 shares of common stock for issuance under the 2006 Plan.

Under the 2006 Plan, we issue new shares of common stock upon exercise of stock options. The number of shares of common stock reserved for issuance automatically increases on January 1st of each year, from January 1, 2007 through January 1, 2016, by the lesser of (a) 4.5% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or (b) 1,400,000 shares. The maximum number of shares that may be issued pursuant to the exercise of incentive stock options under the 2006 Plan is equal to the total shares reserved, as increased from time to time pursuant to annual increases and shares subject to options granted pursuant to the 2001 Plan that have expired without being exercised in full.

As a result of the OMONTYS recall and subsequent reduction in force of almost all personnel the majority of outstanding options were forfeited and returned to the plan in 2013. The only participants in the plan include Board members and the remaining employees. There were ~~312~~4,~~214~~ 906,238 total shares available for grant, combined, under the 2001 and 2006 Plans as of December 31, ~~2012~~2013.

2006 Employee Stock Purchase Plan

Upon the effectiveness of our initial public offering in December 2006, we adopted the 2006 Employee Stock Purchase Plan or the Purchase Plan. As ~~of December 31, 2012 , we reserved~~ a ~~total~~result of ~~748,158 for issuance under~~ the ~~Purchase~~OMONTYS ~~Plan~~recall ofand ~~which~~subsequent ~~21,723~~reduction ~~shares~~in ~~are~~force ~~available to be issued. The share reserve automatically increases on January 1st~~ of ~~each~~almost ~~year,~~all ~~from~~personnel ~~January 1, 2007 through January 1, 2016, by an amount equal to~~ the ~~lesser~~Board of ~~(i) 0.5%~~Directors ofelected ~~the total number of shares of common stock outstanding on December 31 of the preceding calendar year or (ii) 175,000 shares. We issue new shares of common stock~~ in ~~connection~~May ~~with~~2013 ~~purchases~~to ofterminate ~~common~~future ~~stock~~offerings under the ~~Purchase~~Employee ~~Plan. The~~Stock Purchase Plan ~~permits eligible employees to purchase common stock at a discount through payroll deductions during defined offering periods~~. ~~The price at which the stock is purchased is equal to the lower of 85% of the fair market value of the common stock at the beginning of an offering period or at the end of a purchase period.~~ For the year ended December 31, 2013, 2012, ~~2011,~~ and ~~2010~~2011, 0, 224,908, and 184,382 ~~and 130,315~~ shares of common stock, respectively, were purchased under the Purchase Plan.

11. Stock-Based Compensation

~~Stock-based~~During ~~compensation~~the ~~was~~year ~~recorded~~ended inDecember ~~the~~31, ~~statements~~2013, we terminated substantially all of ~~operations~~our asemployees. Upon ~~follows~~termination, (the difference between the expected forfeiture rate and the actual forfeiture rate was adjusted in ~~thousands):~~ the recognition of the stock-

	Year ended December 31,
	2012		2011		2010
Research and development	$	4,324	$	4,632	$	4,521
Selling, general and administrative	6,887		5,393		7,002
Total	$	11,211	$	10,025	$	11,523

We granted the following stock options and RSUs to employees and directors as follows:

	Year ended December 31,
	2012			2011			2010
	Number ofShares	Weighted-Average GrantDate Fair ValuePer Share		Number ofShares	Weighted-Average GrantDate Fair ValuePer Share		Number ofShares	Weighted-Average GrantDate Fair ValuePer Share
Stock options	2,142,286	$	8.26	1,110,924	$	4.41	1,999,999	$	9.64
Restricted stock units	184,963	$	7.99	220,856	$	6.96	460,158	$	6.03

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Asbased ~~of December 31~~compensation, ~~2012,~~and ~~there~~resulted ~~was~~in ~~unrecognized~~an ~~compensation~~offset ~~cost of $22.2 million related~~ to ~~these~~expense ~~stock~~for ~~options~~some ~~and~~groups ~~RSUs~~of employees. ~~The~~ ~~unrecognized~~Stock-based compensation ~~cost~~was asrecorded ofin ~~December 31,~~the ~~2012~~statements isof ~~expected~~operations toas befollows ~~recognized over a weighted-average amortization period of 2.7~~(in ~~years.~~thousands):



	Year ended December 31,
	2013		2012		2011
Research and development	$	878	$	4,324	$	4,632
Selling, general and administrative	3,564		6,887		5,393
Total	$	4,442	$	11,211	$	10,025

We granted the following stock options and RSUs to employees and directors as follows:



	Year ended December 31,
	2013			2012			2011
	Number of Shares	Weighted- Average Grant Date Fair Value Per Share		Number of Shares	Weighted- Average Grant Date Fair Value Per Share		Number of Shares	Weighted- Average Grant Date Fair Value Per Share
Stock options	888,778	$	15.79	2,142,286	$	8.26	1,110,924	$	4.41
Restricted stock units	393,195	$	16.36	184,963	$	7.99	220,856	$	6.96

As of December 31, 2013, there was unrecognized compensation cost of $2.4 million related to these stock options and RSUs. The unrecognized compensation cost as of December 31, 2013 is expected to be recognized over a weighted-average amortization period of 1.8 years.

Valuation assumptions and expense recognition

We estimate the fair value of employee and director stock options using the Black-Scholes valuation model. The fair value of employee and director stock options is amortized on a straight-line basis over the requisite service period of the awards. The fair value of employee and director stock options was estimated using the following weighted-average assumptions for the years ended December 31, ~~2012~~2013, ~~2011~~2012, and ~~2010~~2011:

	Year ended December 31,
	2012		2011		2010
	2013		2012		2011
Expected volatility	81120	%	8081	%	8180	%
Risk-free interest rate	0.8977	%	10.8689	%	21.1086	%
Dividend yield	0.00	%	0.00	%	0.00	%
Expected term (in years)	5.54		5.65		5.56

The expected term of stock options represents the average period the stock options are expected to remain outstanding. For the year ended December 31, ~~2012~~2013, the expected term was based on our historical information on employee exercise and post-vesting employment termination behavior. For the years ended December 31, ~~2011~~2012 and ~~2010~~2011, the expected term was based on the expected terms for industry peers as we did not have sufficient historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior. The expected stock price volatility for our stock options for the year ended December 31, ~~2012~~2013 was based on our historical volatility of our common stock. The expected stock price volatility for our stock options for the years ended December 31, ~~2011~~2012 and ~~2010~~2011 was determined by examining the historical volatilities for industry peers and using an average of the historical volatilities of our industry peers as we did not have any significant trading history for our common stock. Industry peers consist of several public companies in the biopharmaceutical industry similar in size, stage of life cycle and financial leverage. The risk-free interest rate assumption is based on the U.S. Treasury instruments whose term was consistent with the expected term of our stock options. The expected dividend assumption is based on our history and expectation of dividend payouts.

We measured the fair value of RSUs using the closing price of our stock on the grant date. The fair value of RSUs is being amortized on a straight-line basis over the requisite service period of the awards.

We estimated the fair value of employee stock purchase rights granted under the Purchase Plan using the Black-Scholes valuation model. The weighted-average fair value of each stock purchase right for the years ended December 31, ~~2012~~2013, ~~2011~~2012, and ~~2010~~2011 was $40.3600, $24.~~63,~~36 and $32.6463 per share, respectively. ~~The~~As ~~fair value of employee stock purchase rights is being amortized on~~ a ~~straight-line~~result ~~basis over the requisite service period~~ of the ~~purchase~~OMONTYS ~~rights. The~~recall ~~fair value of employee stock purchase rights were estimated using the following assumptions for the years ended December 31, 2012, 2011~~ and ~~2010:~~subsequent

	Year ended December 31,
	2012	2011	2010
Expected volatility	50%-106%	50%-157%	85%-193%
Risk-free interest rate	0.04%-0.57%	0.04%-1.00%	0.16%-1.44%
Dividend yield	—%	—%	—%
Expected term (in months)	6-24	6-24	6-24

The expected term of employee stock purchase rights represents the period the employee stock purchase rights are expected to remain outstanding. The Purchase Plan permits eligible employees to purchase common stock at 6 month intervals at a discount through payroll deductions during defined offering periods. The expected stock price volatility for the year ended December 31, 2012 was based on our historical volatility of our common stock. The expected stock price volatility for the years ended December 31, 2011 and 2010 was determined by examining the historical volatilities for industry peers and using an average of the historical volatilities of our industry peers as we did not have any significant trading history for our common stock. Industry peers consist of several public companies in the biopharmaceutical industry similar in size, stage of life cycle and financial leverage. The risk-free interest rate assumption is based on the U.S. Treasury

Table of Contents

~~instruments~~reduction ~~whose~~in ~~term~~force ~~was~~of ~~consistent~~almost ~~with~~all personnel the ~~expected~~Board ~~term~~ of ~~our~~Directors elected in May 2013 to terminate future offerings under the Employee Stock Purchase Plan. There were no purchases in 2013. The fair value of employee stock purchase rights~~. The~~ ~~expected~~were ~~dividend~~estimated ~~assumption~~using isthe ~~based~~following onassumptions ~~our~~for ~~history~~the ~~and~~years ~~expectation~~ended ofDecember 31, ~~dividend~~2013, ~~payouts.~~2012 and 2011:

There were no tax benefits related to employee stock-based compensation for the years ended December 31, 2012, 2011, and 2010.



	Year ended December 31,
	2013	2012	2011
Expected volatility	—%	50%-106%	50%-157%
Risk-free interest rate	—%	0.04%-0.57%	0.04%-1.00%
Dividend yield	—%	—%	—%
Expected term (in months)	—	6-24	6-24

The expected term of employee stock purchase rights represents the period the employee stock purchase rights are expected to remain outstanding. The Purchase Plan permits eligible employees to purchase common stock at 6 month intervals at a discount through payroll deductions during defined offering periods. The expected stock price volatility for the years ended December 31, 2012 and 2011 was determined by examining the historical volatilities for industry peers and using an average of the historical volatilities of our industry peers as we did not have any significant trading history for our common stock. Industry peers consist of several public companies in the biopharmaceutical industry similar in size, stage of life cycle and financial leverage. The risk-free interest rate assumption is based on the U.S. Treasury instruments whose term was consistent with the expected term of our employee stock purchase rights. The expected dividend assumption is based on our history and expectation of dividend payouts.

There were no tax benefits related to employee stock-based compensation for the years ended December 31, 2013, 2012, and 2011.

Stock Option and Restricted Stock Unit Activity

The following tables summarize information about stock option and RSU activity for the year ended December 31, ~~2012~~2013:

	Number ofShares		Weighted-Average Exercise Price(Per Share)(1)		Weighted-AverageRemainingContractualTerm(in years)	AggregateIntrinsic Value(in thousands)(2)
Stock Options:
Balances at December 31, 2011	4,261,509		$	14.12
Balances at December 31, 2012	4,857,536		$	13.49
Granted	2888,~~142,286~~778		1118.9983
Exercised (3)	(130,~~129,422~~918	)	108.6577
Forfeited	(~~184~~2,~~387~~889,025	)	1013.4435
Cancelled	(~~232~~986,~~450~~514	)	2713.5574
Balances at December 31, 2012	4,857,536		$	13.49	7.73

Filing Compare · AFFYMAX INC