Business and Organization	12 Months Ended
Dec. 31, 2022
Business and Organization
Business and Organization	Note 1. Business and Organization Business Overview Aceragen, Inc. (“Aceragen” or the “Company”) (f/k/a Idera Pharmaceuticals, Inc. (“Idera”)), a Delaware corporation, is a clinical-stage biopharmaceutical company with a business strategy focused on the clinical development, and ultimately the commercialization, of drug candidates for rare disease indications characterized by small, well-defined patient populations with serious unmet medical needs. The Company’s current focus is to develop and optimize commercial value of ACG-701 (patented formulation of sodium fusidate) and ACG-801 (recombinant human acid ceramidase (rhAC)) for appropriate patients. The Company has in the past and may in the future explore clinical funding arrangements and collaborative alliances to support development and commercialization of any of its drug candidates. The Company may also seek to identify and potentially acquire rights to novel development or commercial stage rare disease programs, through new business development opportunities, including additional strategic alternatives. On September 28, 2022 (the “Effective Date”), Idera acquired Aceragen, Inc. and its wholly owned subsidiaries (“Legacy Aceragen”), in accordance with the terms of the Agreement and Plan of Merger, dated as of the Effective Date (the “Merger Agreement”). Legacy Aceragen was a privately-held biotechnology company addressing severe, rare, and orphan pulmonary and rheumatic diseases for which there are limited or no available treatments. The Company acquired Legacy Aceragen as a strategic extension of its rare disease business and focus with the primary objective of further developing Legacy Aceragen’s portfolio of rare disease product candidates. Following the Special Meeting of Stockholders held on January 12, 2023 (the “Special Meeting”), Idera’s name was changed to Aceragen, Inc. (the “Merger” and, together with the other transactions contemplated by the Merger Agreement, the “Aceragen Acquisition”). See Note 3, “Business Acquisition,” for additional information on the Aceragen Acquisition. Prior to December 2021, the Company was developing a toll-like receptor agonist, tilsotolimod (IMO-2125), for oncology indications. In December 2021, all Company-sponsored development of tilsotolimod was discontinued and all study-related activities have subsequently been concluded. However, the Company is considering the potential for out-licensing arrangements so that tilsotolimod’s full potential might continue to be explored on behalf of patients who did not respond to traditional immunotherapy, together with other alternatives. Liquidity and Financial Condition The Company follows the provisions of Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 205-40, Presentation of Financial Statements—Going Concern, which requires management to assess the Company’s ability to continue as a going concern within one year after the date the consolidated financial statements are issued. The Company has incurred substantial losses and negative cash flows from operations since its inception and had an accumulated deficit of $758.8 million as of December 31, 2022. The Company’s cash and cash equivalents balance of $12.0 million as of December 31, 2022 is not sufficient to fund its operations for the one-year period after the date the financial statements are issued. These factors raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The consolidated financial statements do not include any adjustments related to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. The Company anticipates incurring additional losses until such time, if ever, that it can generate significant sales of its product candidates currently in development. The Company is subject to a number of risks and uncertainties similar to those of other companies of the same size within the biotechnology industry, such as uncertainty of clinical trial outcomes, uncertainty of additional funding, and history of operating losses. Substantial additional financing will be needed by the Company to fund its operations and to commercially develop its product candidates. Management is currently evaluating different strategies to obtain the required funding for future operations. These strategies may include, but are not limited to: product development financing, private placements and/or public offerings of equity and/or debt securities, payments from potential strategic research and development collaborations and/or similar arrangements, and payments from the potential sale and/or licensing of technology assets. There can be no assurance that these future funding efforts will be successful. Accordingly, management has concluded that substantial doubt exists with respect to the Company’s ability to continue as a going concern within one year after the date that these financial statements are issued. Reverse Stock Split As further described in Note 19, on January 17, 2023, the Company effected a 1-for-17 reverse stock split of the Company's outstanding shares of common stock, as approved by the Company’s stockholders at the Special Meeting. All share and per share amounts of common stock, options, warrants, restricted stock, restricted stock units, and conversion ratio of convertible preferred stock and convertible preferred stock warrants in the accompanying consolidated financial statements and notes thereto have been retroactively adjusted for all periods presented to reflect the reverse stock split.

Business and Organization

12 Months Ended

Dec. 31, 2022

Note 1. Business and Organization

Business Overview

Aceragen, Inc. (“Aceragen” or the “Company”) (f/k/a Idera Pharmaceuticals, Inc. (“Idera”)), a Delaware corporation, is a clinical-stage biopharmaceutical company with a business strategy focused on the clinical development, and ultimately the commercialization, of drug candidates for rare disease indications characterized by small, well-defined patient populations with serious unmet medical needs. The Company’s current focus is to develop and optimize commercial value of ACG-701 (patented formulation of sodium fusidate) and ACG-801 (recombinant human acid ceramidase (rhAC)) for appropriate patients. The Company has in the past and may in the future explore clinical funding arrangements and collaborative alliances to support development and commercialization of any of its drug candidates. The Company may also seek to identify and potentially acquire rights to novel development or commercial stage rare disease programs, through new business development opportunities, including additional strategic alternatives.

On September 28, 2022 (the “Effective Date”), Idera acquired Aceragen, Inc. and its wholly owned subsidiaries (“Legacy Aceragen”), in accordance with the terms of the Agreement and Plan of Merger, dated as of the Effective Date (the “Merger Agreement”). Legacy Aceragen was a privately-held biotechnology company addressing severe, rare, and orphan pulmonary and rheumatic diseases for which there are limited or no available treatments. The Company acquired Legacy Aceragen as a strategic extension of its rare disease business and focus with the primary objective of further developing Legacy Aceragen’s portfolio of rare disease product candidates.

Following the Special Meeting of Stockholders held on January 12, 2023 (the “Special Meeting”), Idera’s name was changed to Aceragen, Inc. (the “Merger” and, together with the other transactions contemplated by the Merger Agreement, the “Aceragen Acquisition”). See Note 3, “Business Acquisition,” for additional information on the Aceragen Acquisition.

Prior to December 2021, the Company was developing a toll-like receptor agonist, tilsotolimod (IMO-2125), for oncology indications. In December 2021, all Company-sponsored development of tilsotolimod was discontinued and all study-related activities have subsequently been concluded. However, the Company is considering the potential for out-licensing arrangements so that tilsotolimod’s full potential might continue to be explored on behalf of patients who did not respond to traditional immunotherapy, together with other alternatives.

Liquidity and Financial Condition

The Company follows the provisions of Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 205-40, Presentation of Financial Statements—Going Concern, which requires management to assess the Company’s ability to continue as a going concern within one year after the date the consolidated financial statements are issued.

The Company has incurred substantial losses and negative cash flows from operations since its inception and had an accumulated deficit of $758.8 million as of December 31, 2022. The Company’s cash and cash equivalents balance of $12.0 million as of December 31, 2022 is not sufficient to fund its operations for the one-year period after the date the financial statements are issued. These factors raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The consolidated financial statements do not include any adjustments related to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty.

The Company anticipates incurring additional losses until such time, if ever, that it can generate significant sales of its product candidates currently in development. The Company is subject to a number of risks and uncertainties

similar to those of other companies of the same size within the biotechnology industry, such as uncertainty of clinical trial outcomes, uncertainty of additional funding, and history of operating losses. Substantial additional financing will be needed by the Company to fund its operations and to commercially develop its product candidates. Management is currently evaluating different strategies to obtain the required funding for future operations. These strategies may include, but are not limited to: product development financing, private placements and/or public offerings of equity and/or debt securities, payments from potential strategic research and development collaborations and/or similar arrangements, and payments from the potential sale and/or licensing of technology assets. There can be no assurance that these future funding efforts will be successful. Accordingly, management has concluded that substantial doubt exists with respect to the Company’s ability to continue as a going concern within one year after the date that these financial statements are issued.

Reverse Stock Split

As further described in Note 19, on January 17, 2023, the Company effected a 1-for-17 reverse stock split of the Company's outstanding shares of common stock, as approved by the Company’s stockholders at the Special Meeting. All share and per share amounts of common stock, options, warrants, restricted stock, restricted stock units, and conversion ratio of convertible preferred stock and convertible preferred stock warrants in the accompanying consolidated financial statements and notes thereto have been retroactively adjusted for all periods presented to reflect the reverse stock split.

Aceragen, Inc. 10-K