UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): October 20, 2025

Disc Medicine, Inc.

(Exact name of Registrant as Specified in Its Charter)

Delaware	001-39438	85-1612845
(State or Other Jurisdictionof Incorporation)	(~~CommissionFile~~Commission File Number)	(IRS EmployerIdentification No.)
321 Arsenal Street, Suite 101
Watertown, Massachusetts		02472
(Address of Principal Executive Offices)		(Zip Code)

Registrant’s Telephone Number, Including Area Code: (617) 674-9274

N/A

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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

Title of each class		TradingSymbol(s)		Name of each ~~exchange~~exchangeon on which registered
Common Stock, par value $0.0001 per share		IRON		The Nasdaq Global Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☒☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 21.0201 ~~Results~~Entry ofinto ~~Operations~~a ~~and~~Material ~~Financial~~Definitive ~~Condition~~Agreement.

On October 20, 2025, Disc Medicine, Inc. (the “Company”) ~~announced~~entered ~~that~~into ~~its~~an ~~preliminary~~Underwriting ~~unaudited~~Agreement ~~cash~~(the “Underwriting Agreement”) with Jefferies LLC, ~~cash~~Leerink ~~equivalents~~Partners LLC, Morgan Stanley & Co. LLC and ~~marketable~~Cantor ~~securities~~Fitzgerald & Co., as representatives of ~~September~~the several underwriters listed on Schedule I thereto (the “Underwriters”) and AI DMI LLC, as a selling stockholder (the “Selling Stockholder”), related to an underwritten offering (the “Offering”) (i) by the Company of (a) 2,619,049 shares of common stock of the Company, par value $0.0001 per share (the “Common Stock”) at a price to the public of $84.00 per share and (b) 30in lieu of Common Stock to certain investors, ~~2025~~pre-funded ~~were~~warrants ~~approximately~~to purchase an aggregate of 59,523 shares of Common Stock (the “Pre-Funded Warrants”) at a price to the public of $~~615~~83.99999 per Pre-Funded Warrant, which represents the per share public offering price for the Common Stock less the $0.0001 per share exercise price for each such ~~million~~Pre-Funded Warrant, and (ii) by the Selling Stockholder of 297,619 shares of Common Stock at a price to the public of $84.00 per share. In addition, the Selling Stockholder granted the Underwriters an option exercisable for 30 days from the date of the Underwriting Agreement to purchase, at the public offering price less any underwriting discounts and commissions, up to an additional 446,428 shares of Common Stock, which the Underwriters exercised in full on October 21, 2025.

The ~~Company~~net ~~has~~proceeds ~~not~~to ~~yet~~the ~~completed~~Company ~~its quarter-end~~from ~~financial~~the ~~close~~Offering ~~process~~are ~~for~~expected ~~the~~to ~~quarter~~be ~~ended~~approximately ~~September~~$210.9 30million, ~~2025.~~after ~~This~~deducting ~~estimate~~the ofunderwriting ~~the~~discount ~~Company’s~~and ~~cash,~~estimated ~~cash~~offering ~~equivalents~~expenses. ~~and~~The ~~marketable~~Company ~~securities~~will asreceive ofnominal ~~September 30~~proceeds, ~~2025~~if ~~is preliminary~~any, ~~has~~from ~~not~~the ~~been~~exercise ~~audited and is subject to change upon completion~~ of the ~~Company’s~~Pre-Funded ~~financial statement closing procedures~~Warrants. ~~Additional~~The ~~information~~Company ~~and~~will ~~disclosure~~not ~~would~~receive beany ~~required~~proceeds ~~for~~from ~~a more complete understanding of~~ the ~~Company’s~~sale ~~financial position and results~~ of ~~operations~~shares asby ofthe ~~September 30,~~Selling ~~2025~~Stockholder. The Company’s ~~independent~~expects ~~registered~~that ~~public~~its ~~accounting firm has not audited~~cash, ~~reviewed~~cash orequivalents ~~performed~~and ~~any~~marketable ~~procedures~~securities, together with ~~respect~~the toestimated ~~this~~net ~~preliminary~~proceeds ~~result~~from ~~and,~~the ~~accordingly~~Offering, ~~does~~will ~~not~~be ~~express~~sufficient anto ~~opinion~~fund orits ~~any~~current ~~other~~operating ~~form~~and ofcapital ~~assurance~~expenditure ~~about~~plans ~~it.~~into ~~The~~2029, ~~information~~without ~~presented~~taking ~~herein~~into ~~should~~account ~~not~~any bepotential ~~considered~~cash ainflows ~~substitute~~from ~~for~~bitopertin ~~the~~or ~~financial~~any ~~information~~other ~~the~~marketed ~~Company~~product, ~~files~~if ~~with~~approved ~~the~~during ~~Securities~~such ~~and~~period. ~~Exchange~~The ~~Commission~~Offering ~~(the~~is ~~“SEC”)~~expected into ~~its~~close ~~quarterly report~~ on ~~Form 10-Q for the quarter ended September~~October 3022, 2025. ~~The Company has no intention or obligation to update preliminary estimates of its cash, cash equivalents and marketable securities set forth above.~~

~~The~~Each ~~information~~Pre-Funded ~~contained~~Warrant inwill ~~Item~~be ~~2.02~~exercisable for one share of ~~this~~Common ~~Current~~Stock ~~Report~~at ~~on Form 8-K~~an isexercise ~~intended~~price toof be$0.0001 ~~furnished~~per ~~and~~share, ~~shall~~or ~~not~~alternatively, beat ~~deemed~~the toelection of each holder, shares of Common Stock may be ~~“filed”~~issued ~~for~~through a cashless exercise, with the ~~purposes~~net number of ~~Section 18~~shares of Common Stock determined according to the ~~Securities~~formula set forth in each Pre-Funded Warrant. The Pre-Funded Warrants will be immediately exercisable and ~~Exchange~~may ~~Act~~be exercised at any time until all of ~~1934,~~the asPre-Funded ~~amended~~Warrants are exercised in full. A holder (~~the~~together with its “~~Exchange~~attribution ~~Act~~parties,” as defined in the Pre-Funded Warrant), ormay ~~otherwise~~not ~~subject~~exercise toany portion of the ~~liabilities~~Pre-Funded ofWarrants ~~that~~if ~~section~~immediately after exercise, ~~nor~~the ~~shall~~holder it(together bewith ~~deemed~~its ~~incorporated~~attribution byparties), ~~reference~~would beneficially own in ~~any~~excess ~~filing~~of ~~under~~24.99% of the ~~Securities~~number ~~Act~~of shares of ~~1933,~~Common asStock ~~amended~~outstanding immediately after giving effect to the exercise (the “~~Securities~~Ownership ~~Act~~Limit”). Purchasers of the Pre-Funded Warrants may also elect to set the initial Ownership Limit at 4.99%, 9.99% or 19.99%. Upon at least 61 days’ prior notice from the ~~Exchange~~holder ~~Act~~to the Company, ~~except~~the asholder ~~expressly~~may increase or decrease the Ownership Limit up to 24.99%, provided byhowever ~~specific~~that ~~reference~~purchasers inthat select an Ownership Limit of 19.99% or less will only be allowed to increase the Ownership Limit above 19.99% if such ~~filing~~increase would not result in a change of control under the rules and regulations of the Nasdaq Stock Market LLC.

~~Item~~In 7addition, if the exercise of a Pre-Funded Warrant would result in a holder of Pre-Funded Warrants (together with its attribution parties) acquiring beneficial ownership of Common Stock (together with all other equity owned by such holder at such time) equal to or in excess of the notification threshold applicable to such holder (the “HSR Threshold”) under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the “HSR Act”), as of the date of delivery of the applicable exercise notice, and no exemption to filing a notice and report form under the HSR Act is applicable, then only such portion of the Pre-Funded Warrants held by such holder, which when exercised does not exceed the HSR Threshold, shall be exercisable and the applicable exercise notice shall be deemed to relate only to such portion of the Pre-Funded Warrants, and the remaining portion of the Pre-Funded Warrants in excess of the HSR Threshold shall not be exercisable until the expiration or early termination of the applicable waiting period under the HSR Act or receipt of applicable approval.01 ~~Regulation~~For FDcertain ~~Disclosure~~holders of Pre-Funded Warrants, upon expiration or early termination of the applicable waiting period under the HSR Act or receipt of applicable approval, such holder shall no longer be subject to either the HSR Threshold or the Ownership Limit. The Company does not intend to list the Pre-Funded Warrants on the Nasdaq Global Market, any other national securities exchange or any other nationally recognized trading system.

OnThe ~~October 20,~~Company ~~2025~~made certain customary representations, warranties and covenants concerning the Company ~~issued~~and athe ~~press~~registration ~~release~~statement ~~providing~~in anthe ~~update~~Underwriting onAgreement ~~its~~and ~~hematology~~also ~~portfolio~~agreed ~~and~~to ~~outlining~~indemnify ~~near-term~~the ~~business~~Underwriters ~~objectives~~against certain liabilities, including liabilities under the Securities Act of 1933, as amended (the “Securities Act”). The Selling Stockholder also made certain customary representations, warranties and ~~anticipated~~covenants ~~milestones~~and agreed to indemnify the Underwriters against certain liabilities, including liabilities under the Securities Act. AThe ~~copy~~offering of ~~the~~securities ~~press~~by ~~release~~the Company is ~~attached~~being asmade ~~Exhibit~~pursuant 99to the Company’s automatic shelf registration statement on Form S-3 (File No.1 333-281359), filed with the Securities and Exchange Commission (the “Commission”) on August 8, 2024, and, with respect to ~~this~~the shares being offered by the Selling Stockholder, the Company’s resale registration statement on Form S-3 (File No. 333-269270), filed with the Commission on January 17, 2023, as supplemented by a final prospectus supplement dated October 20, 2025, filed on October 21, 2025. This Current Report on Form 8-K does not constitute an offer to sell or a solicitation of an offer to buy any of the shares of Common Stock or the Pre-Funded Warrants.

The ~~information~~foregoing ~~contained~~description inof ~~Item~~certain ~~7.01~~terms of ~~this~~the ~~Current~~Underwriting ~~Report~~Agreement onand ~~Form~~the ~~8-K~~transactions ~~(including~~contemplated ~~Exhibit~~thereby ~~99.1~~does ~~attached~~not ~~hereto)~~purport ~~is intended~~ to be ~~furnished~~complete and ~~shall~~is ~~not~~subject beto, ~~deemed~~and ~~“filed”~~qualified ~~for~~in ~~purposes~~its ofentirety ~~Section 18~~by, the full text of the ~~Exchange~~Underwriting ~~Act~~Agreement, orwhich ~~otherwise~~is ~~subject~~attached toas ~~the~~Exhibit ~~liabilities~~1.1 hereto and is incorporated by reference herein. The form of ~~that~~Pre-Funded ~~section,~~Warrant ~~nor~~to ~~shall~~Purchase itCommon beStock ~~deemed~~is filed as Exhibit 4.1 to this Current Report on Form 8-K and is incorporated herein by reference, inand ~~any~~the ~~filing~~foregoing ~~under~~description of the ~~Securities~~terms ~~Act~~of or the ~~Exchange~~Pre-Funded ~~Act,~~Warrants ~~except~~is asqualified ~~expressly~~in ~~provided~~its entirety by ~~specific~~ reference into such ~~filing~~exhibit. ~~The~~A ~~Company~~copy ~~undertakes~~of nothe ~~obligation~~opinion of Goodwin Procter LLP, relating to ~~update~~the legality of the shares of Common Stock, ~~supplement~~the orPre-Funded ~~amend~~Warrants and the ~~materials~~shares ~~attached~~of ~~hereto~~Common Stock issuable upon exercise of the Pre-Funded Warrants, is filed as Exhibit 995.1 hereto and is incorporated by reference herein.

Item 8.01

Other Events.

~~Corporate~~On ~~Presentation~~October 20, 2025, the Company issued a press release announcing the commencement of the Offering. On October 21, 2025, the Company issued a press release announcing that it had priced the Offering. Copies of these press releases are attached hereto as Exhibit 99.1 and Exhibit 99.2, respectively, and are incorporated by reference herein.

OnCautionary ~~October 20,~~Statement ~~2025,~~Regarding ~~the Company updated its corporate presentation. A copy of the updated corporate presentation is filed as Exhibit 99.2 to this Current Report on Form 8~~Forward-KLooking ~~and~~Statements incorporated herein by reference. The corporate presentation will also be available in the investor relations section of the Company’s website at https://ir.discmedicine.com. Information contained on the Company’s website is not incorporated by reference into this Current Report on Form 8-K, and you should not consider any information on, or that can be accessed from, the Company’s website as part of this Current Report on Form 8-K.

~~Recent~~This ~~Developments~~Current Report on Form 8-K contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to, express or implied statements regarding the Company’s anticipated cash runway. The use of words such as, but not limited to, “believe,” “expect,” “estimate,” “project,” “intend,” “future,” “potential,” “continue,” “may,” “might,” “plan,” “will,” “should,” “seek,” “anticipate,” or “could” or the negative of these terms and other similar words or expressions are intended to identify forward-looking statements. Forward-looking statements are neither historical facts nor assurances of future performance. Instead, they are based on the Company’s current beliefs, expectations and assumptions regarding the future of the Company’s business, future plans and strategies, clinical results and other future conditions. New risks and uncertainties may emerge from time to time, and it is not possible to predict all risks and uncertainties. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements.

OnThe ~~October 20~~Company may not actually achieve the plans, ~~2025~~intentions or expectations disclosed in these forward-looking statements, and investors should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements as a result of a number of material risks and uncertainties including but not limited to: the nature, strategy and focus of the Company; ~~provided~~the andifficulty ~~update~~in onpredicting the time and cost of development of the Company’s product candidates; the Company’s plans to research, develop and commercialize its ~~hematology~~current ~~portfolio~~and future product candidates; the timing of initiation of the Company’s planned preclinical studies and ~~outlined~~clinical trials; the timing of the availability of data from the Company’s clinical trials; the Company’s ability to identify additional product candidates with significant commercial potential and to expand its ~~near-term~~pipeline ~~business~~in ~~objectives~~hematological diseases; the timing and anticipated ~~milestones~~results ~~for~~of the ~~rest~~Company’s preclinical studies and clinical trials and the risk that the results of ~~2025~~the Company’s preclinical studies and ~~2026:~~clinical trials may not be predictive of future results in connection with future studies or clinical trials and may not support further development and marketing approval; the content and timing of decisions made by the U.S. Food and Drug Administration and other regulatory authorities; and the other risks and uncertainties described in the Company’s filings with the Securities and Exchange Commission, including in the “Risk Factors” section of the Company’s Annual Report on Form 10-K for the year ended December 31, 2024 and in the Company’s Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2025. Any forward-looking statement speaks only as of the date on which it was made. None of the Company, nor its affiliates, advisors or representatives, undertake any obligation to publicly update or revise any forward-looking statement, whether as result of new information, future events or otherwise, except as required by law.

~~Bitopertin:~~Item ~~GlyT1~~9.01 ~~Inhibitor (Heme Synthesis Modulator)~~ Exhibits.

• Accelerate activities to support a potential US approval and launch in late 2025 or early 2026 based on accelerated review timeline associated with receipt of the FDA Commissioner’s National Priority Voucher (“CNPV”), which is designed to shorten the New Drug Application review process to 1-2 months

• Drive enrollment of ongoing APOLLO confirmatory trial of bitopertin in erythropoietic protoporphyria that is intended to also support potential approval of bitopertin in territories outside the US

DISC-0974: Anti-hemojuvelin Antibody (Hepcidin Suppression)

• Progress and position DISC-0974 to be advanced into potential late-stage clinical development for anemia of myelofibrosis (“MF”)

• Initial data from ongoing Phase 2 study in anemia of MF to be reported by year end; topline data expected in 2026, if positive, is anticipated to support discussion with regulatory agencies on registrational path

• Demonstrate role of hepcidin suppression and anti-hemojuvelin (“HJV”) mechanism in other anemias of chronic disease:

• Recently completed Phase 1b double-blind, placebo-controlled study of DISC-0974 demonstrated engagement of mechanism in anemia of non-dialysis dependent chronic kidney disease with variable effects on hemoglobin

• DISC-0974 was generally well-tolerated with substantial decreases in hepcidin, increases in iron, and improvements in markers of erythropoiesis

• Meaningful hemoglobin increases observed in only a subset of patients were in part driven by those with higher baseline erythropoietin (“EPO”) levels

• Full data will be shared at the upcoming 2025 ASN Kidney Week; the Company is assessing options for the program based on full analysis of the data

• Initiation of a Phase 2 study in patients with inflammatory bowel disease and anemia anticipated in Q1 2026, and planning exploratory studies in additional patient populations with anemia of chronic disease.

• Plans to accelerate next-generation, long-acting anti-HJV antibody into IND-enabling studies

DISC-3405: Anti-TMPRRS6 Antibody (Hepcidin Induction)

• Establish Phase 2 proof-of-concept of DISC-3405 for polycythemia vera (“PV”) and support potential development into later stage development

• Topline data from ongoing Phase 2 study in PV expected in 2026

• Initiation of Phase 1b study in patients with sickle cell disease anticipated by year end

• Plans to explore the role of therapeutic iron restriction in other indications

This Current Report on Form 8-K contains forward-looking statements within the meaning of Section 27A of the Securities Act, and Section 21E of the Exchange Act. Any statements about the Company’s expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and may be forward-looking. These statements are often, but are not always, made through the use of words or phrases such as “may,” “will,” “could,” “should,” “expects,” “intends,” “plans,” “anticipates,” “believes,” “estimates,” “predicts,” “projects,” “seeks,” “endeavor,” “potential,” “continue,” and similar expressions, or the negative of these terms, or similar expressions. These forward-looking statements include statements about the Company’s expectations with respect to the next stages of its development programs for bitopertin, DISC-0974 and DISC-3405, including projected timelines for the initiation and completion of its clinical trials, anticipated timing of release of data, and other clinical activities; the registrational pathway for bitopertin, including the potential for accelerated approval, benefits of the CNPV and expected review period; anticipated discussions with regulatory agencies; ongoing preparations for the potential launch of bitopertin; and the potential of its development programs in new indications. Accordingly, these statements involve estimates, assumptions, risks and uncertainties which could cause actual results to differ materially from those expressed in them, including the uncertainties related to market conditions and the completion of the public offering on the anticipated terms or at all. The Company’s forward-looking statements also involve assumptions that, if they prove incorrect, would cause its results to differ materially from those expressed or implied by such forward-looking statements. These and other risks concerning the Company’s business are described in additional detail in the Company’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2025 and other documents filed by the Company from time to time with the SEC. The Company is under no obligation to, and expressly disclaims any such obligation to, update or alter its forward-looking statements, whether as a result of new information, future events or otherwise.

Item 9.01. Exhibits.

(d) Exhibits

ExhibitNo.		Description
99.1		Press release issued by Disc Medicine, Inc. on October 20, 2025, furnished herewith.
1.1		Underwriting Agreement, dated as of October 20, 2025, by and among the Company, AI DMI LLC and Jefferies LLC, Leerink Partners LLC, Morgan Stanley & Co. LLC and Cantor Fitzgerald & Co., as representatives of the several underwriters listed on Schedule I thereto.
99.2		Disc Medicine, Inc. Investor Presentation, filed herewith.
4.1		Form of Pre-Funded Warrant.
5.1		Opinion of Goodwin Procter LLP regarding the issue of Common Stock, Pre-Funded Warrants and Common Stock issuable upon exercise of the Pre-Funded Warrants being registered.
23.1		Consent of Goodwin Procter LLP (included in Exhibit 5.1).
99.1		Press release announcing the Offering, dated October 20, 2025.
99.2		Press release announcing the pricing of the Offering, dated October 21, 2025.
104		Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	DISC MEDICINE, INC.
Date: October 20, 2025	By:	/s/ John Quisel
Date: October 22, 2025	By:	/s/ John Quisel
	Name:	John Quisel, J.D., Ph.D.
	Title:	Chief Executive Officer

Filing Compare · Disc Medicine, Inc.