Description of Business and Basis of Presentation	6 Months Ended
Jun. 30, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Basis of Presentation	1. Description of Business and Basis of Presentation Larimar Therapeutics, Inc., together with its subsidiary (the “Company” or “Larimar”), is a clinical-stage biotechnology company focused on developing treatments for patients suffering from complex rare diseases using its novel cell penetrating peptide technology platform. Larimar's lead product candidate, nomlabofusp, is a subcutaneously administered, recombinant fusion protein intended to deliver human frataxin (“FXN”), an essential protein, to the mitochondria of patients with Friedreich's Ataxia (“FA”). FA is a rare, progressive, and fatal disease in which patients are unable to produce sufficient FXN due to a genetic abnormality. Basis of Presentation The condensed consolidated financial statements include the accounts of Larimar and its wholly owned subsidiary. All intercompany balances and transactions have been eliminated. The accompanying condensed consolidated financial statements have been prepared in conformity with U.S. Generally Accepted Accounting Principles (“GAAP”). The consolidated balance sheet as of December 31, 2025 was derived from the Company’s audited financial statements but does not include all disclosures required by GAAP. The accompanying unaudited condensed consolidated financial statements as of June 30, 2026 and for the three and six months ended June 30, 2026 and 2025, have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. However, the Company believes that the disclosures are adequate to make the information presented not misleading. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2025 included in the Company’s Annual Report on Form 10-K filed with the SEC on March 19, 2026. In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s condensed consolidated financial position as of June 30, 2026, condensed consolidated results of operations for the three and six months ended June 30, 2026 and condensed consolidated statement of cash flows for the six months ended June 30, 2026 have been made. The results of operations for the three and six months ended June 30, 2026 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2026. Liquidity and Capital Resources Since its inception, the Company has incurred significant recurring operating losses and negative cash flows from operations. The Company has incurred net losses of $62.4 million and $55.5 million for the six months ended June 30, 2026 and 2025, respectively. In addition, as of June 30, 2026, the Company had an accumulated deficit of $497.2 million. The Company expects to continue to generate operating losses for the foreseeable future. As of June 30, 2026, the Company had approximately $156.3 million of cash, cash equivalents and marketable securities available for use to fund its operations and capital requirements. The Company has funded its operations to date primarily with proceeds from sales of common stock and proceeds from the sale of prefunded warrants for the purchase of common stock, the acquisition in 2020 of cash, cash equivalents and marketable securities upon the merger with Zafgen, Inc. (“Zafgen”) and, prior to the 2020 merger with Zafgen, capital contributions from Chondrial Holdings, LLC. In July 2025, the Company completed an underwritten public offering of common stock raising net proceeds of approximately $65.0 million. In February 2026, the Company completed another underwritten public offering of common stock raising net proceeds of approximately $107.6 million. Going Concern In accordance with Accounting Standards Update (“ASU”) No. 2014-15, “Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern”, the Company has evaluated whether there are certain conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that these unaudited condensed consolidated financial statements are issued. While the Company expects its cash, cash equivalents and marketable securities will fund its forecasted operating expenses and capital expenditure requirements into the third quarter of 2027, these cash resources are not sufficient to fund the Company’s planned operations for a period of at least one year from the date these unaudited condensed consolidated financial statements are issued. The Company will need to raise additional capital to fund its ongoing operations. The Company continues to evaluate opportunities to further finance its operating cash needs through a combination of some, or all, of the following: equity or debt offerings, royalty financings, collaborations, strategic alliances, and/or marketing, distribution or licensing arrangements. In addition, the Company believes it will be eligible for the FDA's rare pediatric disease priority review voucher which could then be sold if nomlabofusp receives FDA approval. There is no assurance, however, that additional financing will be available when needed or that the Company will be able to obtain financing on terms acceptable to the Company. If the Company is unable to obtain funding when required in the future, the Company could be required to delay, reduce, or eliminate research and development programs, or commercialization efforts, which could adversely affect its business prospects. These conditions raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying unaudited condensed consolidated financial statements have been prepared assuming the Company will continue as a going concern, which contemplates the realization of assets and satisfaction of liabilities in the normal course of the business. The unaudited condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classifications of liabilities that might result from the outcome of this uncertainty.

Larimar Therapeutics, Inc., together with its subsidiary (the “Company” or “Larimar”), is a clinical-stage biotechnology company focused on developing treatments for patients suffering from complex rare diseases using its novel cell penetrating peptide technology platform. Larimar's lead product candidate, nomlabofusp, is a subcutaneously administered, recombinant fusion protein intended to deliver human frataxin (“FXN”), an essential protein, to the mitochondria of patients with Friedreich's Ataxia (“FA”). FA is a rare, progressive, and fatal disease in which patients are unable to produce sufficient FXN due to a genetic abnormality.

Basis of Presentation

The condensed consolidated financial statements include the accounts of Larimar and its wholly owned subsidiary. All intercompany balances and transactions have been eliminated. The accompanying condensed consolidated financial statements have been prepared in conformity with U.S. Generally Accepted Accounting Principles (“GAAP”).

The consolidated balance sheet as of December 31, 2025 was derived from the Company’s audited financial statements but does not include all disclosures required by GAAP. The accompanying unaudited condensed consolidated financial statements as of June 30, 2026 and for the three and six months ended June 30, 2026 and 2025, have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. However, the Company believes that the disclosures are adequate to make the information presented not misleading. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2025 included in the Company’s Annual Report on Form 10-K filed with the SEC on March 19, 2026.

In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s condensed consolidated financial position as of June 30, 2026, condensed consolidated results of operations for the three and six months ended June 30, 2026 and condensed consolidated statement of cash flows for the six months ended June 30, 2026 have been made. The results of operations for the three and six months ended June 30, 2026 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2026.

Since its inception, the Company has incurred significant recurring operating losses and negative cash flows from operations. The Company has incurred net losses of $62.4 million and $55.5 million for the six months ended June 30, 2026 and 2025, respectively. In addition, as of June 30, 2026, the Company had an accumulated deficit of $497.2 million. The Company expects to continue to generate operating losses for the foreseeable future. As of June 30, 2026, the Company had approximately $156.3 million of cash, cash equivalents and marketable securities available for use to fund its operations and capital requirements.

The Company has funded its operations to date primarily with proceeds from sales of common stock and proceeds from the sale of prefunded warrants for the purchase of common stock, the acquisition in 2020 of cash, cash equivalents and marketable securities upon the merger with Zafgen, Inc. (“Zafgen”) and, prior to the 2020 merger with Zafgen, capital contributions from Chondrial Holdings, LLC.

In July 2025, the Company completed an underwritten public offering of common stock raising net proceeds of approximately $65.0 million.

In February 2026, the Company completed another underwritten public offering of common stock raising net proceeds of approximately $107.6 million.

Going Concern

In accordance with Accounting Standards Update (“ASU”) No. 2014-15, “Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern”, the Company has evaluated whether there are certain conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that these unaudited condensed consolidated financial statements are issued. While the Company expects its cash, cash equivalents and marketable securities will fund its forecasted operating expenses and capital expenditure requirements into the third quarter of 2027, these cash resources are not sufficient to fund the Company’s planned operations for a period of at least one year from the date these unaudited condensed consolidated financial statements are issued.

The Company will need to raise additional capital to fund its ongoing operations. The Company continues to evaluate opportunities to further finance its operating cash needs through a combination of some, or all, of the following: equity or debt offerings, royalty financings, collaborations, strategic alliances, and/or marketing, distribution or licensing arrangements. In addition, the Company believes it will be eligible for the FDA's rare pediatric disease priority review voucher which could then be sold if nomlabofusp receives FDA approval. There is no assurance, however, that additional financing will be available when needed or that the Company will be able to obtain financing on terms acceptable to the Company. If the Company is unable to obtain funding when required in the future, the Company could be required to delay, reduce, or eliminate research and development programs, or commercialization efforts, which could adversely affect its business prospects. These conditions raise substantial doubt about the Company’s ability to continue as a going concern.

The accompanying unaudited condensed consolidated financial statements have been prepared assuming the Company will continue as a going concern, which contemplates the realization of assets and satisfaction of liabilities in the normal course of the business. The unaudited condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classifications of liabilities that might result from the outcome of this uncertainty.