Larimar Therapeutics, Inc.

Comparison of three months ended June 30, 2026 and 2025

The following table summarizes our results of operations for the three months ended June 30, 2026 and 2025:

Research and development expenses for the three months ended June 30, 2026 increased $4.6 million compared to the three months ended June 30, 2025. The increase in research and development expenses was primarily driven by a $2.3 million increase in process performance qualification, and other drug manufacturing activities at our third-party manufacturers and a $2.0 million increase in professional and consulting fees associated with our ongoing and planned clinical trials, data analysis costs, FDA inspection readiness expenditures, as well as Biologics License Application preparation costs.

General and Administrative expenses

General and administrative expenses for the three months ended June 30, 2026 increased $1.9 million compared to the three months ended June 30, 2025. The increase in general and administrative expenses primarily related to the acceleration of commercial activities as we prepare for the planned mid-2027 launch of nomlabofusp, if approved. This included an increase of $0.7 million of increased compensation costs associated with additional commercial and related headcount, an increase of $0.5 million of market development activities and commercial readiness efforts as well as an increase of $0.5 million in legal fees supporting commercialization and development efforts.

Other Income (expense), net

Other income (expense), net was $1.6 million in the three months ended June 30, 2026 compared to $1.6 million income in the three months ended June 30, 2025.

Comparison of six months ended June 30, 2026 and 2025

The following table summarizes our results of operations for the six months ended June 30, 2026 and 2025:

Research and development expenses for the six months ended June 30, 2026 increased $3.1 million compared to the six months ended June 30, 2025. This increase was driven by a $3.7 million increase in professional and consulting fees associated with our ongoing and planned clinical trials, data analysis costs, inspection readiness expenditures as well as Biologics License Application preparation costs partially offset by lower manufacturing activities and there related costs in the six month period ended June 30, 2026 compared to the six month period ended June 30, 2026.

General and administrative expenses for the six months ended June 30, 2026 increased $3.4 million compared to the six months ended June 30, 2025. The increase in general and administrative expenses primarily related to the acceleration of commercial activities as we prepare for the planned mid-2027 launch of nomlabofusp, if approved. This included an increase of $1.6 million in market research, market development and other commercial readiness activities, an increase of $1.0 million of increased compensation costs associated with additional commercial and related headcount,as well as an increase of $0.5 million in legal fees supporting commercialization and development efforts.

Other Income (expense), net

Other income (expense), net was $3.1 million income in the six months ended June 30, 2026 compared to $3.5 million income in the six months ended June 30, 2025. The decrease was primarily driven by lower interest and accretion income due to lower interest yields and lower average investable cash, cash equivalents, and marketable securities balances.

Liquidity and Capital Resources

Financing Activities, including Recent Material Financings

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

In July 2025, we completed an underwritten public offering in which we issued and sold 21,562,500 shares of our common stock, including the exercise in full of the underwriters' option to purchase additional shares, at a public offering price of $3.20 per share. We received net proceeds of approximately $65.0 million, after deducting underwriting discounts, commissions and other offering expenses.

In February 2026, we completed an underwritten public offering in which we issued and sold 23,000,000 shares of our common stock, including the exercise in full of the underwriters' option to purchase additional shares, at a public offering price of $5.00 per share. We received net proceeds of approximately $107.6 million, after deducting underwriting discounts, commissions, and other offering expenses.

Cash Flows

The following table summarizes our sources and uses of cash for each of the periods presented below:

Net cash used in operating activities

During the six months ended June 30, 2026, operating activities used $88.6 million of cash, resulting from our net loss of $62.4 million, adjusted for noncash expenses of $3.7 million and changes in our operating assets and liabilities resulting in a use of cash of $30.0 million. Our net loss was primarily attributed to research and development activities related to our nomlabofusp program and our general and administrative expenses as described above. Noncash expenses primarily relate to stock-based compensation expenses. The change in operating assets and liabilities was primarily due to decreases in prepaid expenses and accrued expenses, partially offset by an increase in accounts payable.

During the six months ended June 30, 2025, operating activities used $45.9 million of cash, resulting from our net loss of $55.5 million, adjusted for noncash expenses of $2.5 million and changes in our operating assets and liabilities resulting in a source of cash of $7.1 million. Our net loss was primarily attributed to research and development activities related to our nomlabofusp program and our general and administrative expenses as described above. Noncash expenses primarily relate to stock-based compensation expenses. The change in operating assets and liabilities was primarily due to increases in prepaid expenses, accounts payable and accrued expenses.

Net cash provided by (used in) investing activities

During the six months ended June 30, 2026, investing activities used $11.9 million. This use of cash resulted from purchases of $63.3 million of marketable securities, partially offset by the maturities of $51.5 million of marketable securities.

During the six months ended June 30, 2025, investing activities provided $33.3 million. This source of cash resulted from the maturities of $113.5 million of marketable securities partially offset by purchases of $80.1 million of marketable securities.

Net cash provided by financing activities

During the six months ended June 30, 2026, financing activities provided $107.7 million of cash flows from an offering of common stock.

During the six months ended June 30, 2025, there were no financing activities.

Operating Capital Requirements

Since our inception, we have not generated any revenue from any sources, including from product sales, and have incurred significant operating losses and negative cash flows from our operations. We have incurred net losses of approximately $62.4 million and $55.5 million for the six months ended June 30, 2026 and 2025, respectively. As of June 30, 2026, we had an accumulated deficit of $497.2 million. We have devoted substantially all of our resources to developing nomlabofusp, building our intellectual property portfolio, developing third-party manufacturing capabilities, business planning, capital raising, and providing general and administrative support for such operations.

As of June 30, 2026, we had approximately $156.3 million of cash, cash equivalents and marketable securities. In accordance with Accounting Standards Update (“ASU”) No. 2014-15, “Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern”, we have evaluated whether there are certain conditions and events, considered in the aggregate, that raise substantial doubt about our ability to continue as a going concern within one year after the date that these unaudited condensed consolidated financial statements are issued. These cash resources are not sufficient to fund our planned operations for a period of at least one year from the date these financial statements are issued. While we expect our cash, cash equivalents and marketable securities will fund our forecasted operating expenses and capital expenditure requirements into the third quarter of 2027, if we encounter unexpected delays in our clinical trials or if there are other unanticipated changes to our operating plan from our current assumptions that negatively impact our operations, we may reduce expenditures in order to further extend our existing cash resources.

We expect to incur significant expenses and operating losses for the foreseeable future as we expect to continue to incur expenses in connection with our ongoing activities, if and as we:

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continue to advance the development of nomlabofusp through additional clinical trials, including related manufacturing costs;

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seek to identify and advance development of additional product candidates into clinical development and identify additional indications for our product candidates;

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seek to obtain regulatory approvals for nomlabofusp and other potential product candidates;

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identify, acquire or in-license other product candidates and technologies;

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maintain, leverage and expand our intellectual property portfolio; and

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expand our operational, financial, commercial and management systems and personnel, including personnel to support our clinical development and future commercialization efforts and our operations as a public company.

Until we can generate substantial revenue, if ever, we will need to raise additional capital to fund our ongoing operations, and continue to evaluate opportunities to further finance our operating cash needs through a combination of some, or all, of the following: equity, debt and royalty offerings, collaborations, strategic alliances, and/or marketing, distribution or licensing arrangements. There is no assurance, however, that additional financing will be available when needed or that we will be able to obtain financing on terms acceptable to us. If we are unable to obtain funding when required in the future, we could be required to delay, reduce, or eliminate research and development programs, or commercialization efforts, which could adversely affect our business prospects. These conditions raise substantial doubt about our ability to continue as a going concern.

Off-Balance Sheet Arrangements

During the periods presented we did not have, and we currently do not have, any off-balance sheet arrangements, as defined under applicable SEC rules, such as relationships with unconsolidated entities or financial partnerships, which are often referred to as structured finance or special purpose entities, established for the purpose of facilitating financing transactions that are not required to be reflected on our balance sheets.

Recently Issued Accounting Pronouncements

Please read Note 2 to our condensed consolidated financial statements included in Part I of Item 1 of this Quarterly Report on Form 10-Q for a description of recent accounting pronouncements applicable to our business, if any.

Other Company Information

None.