Larimar Therapeutics, Inc.

Comparison of three months ended September 30, 2025 and 2024

The following table summarizes our results of operations for the three months ended September 30, 2025 and 2024:

Research and development expenses for the three months ended September 30, 2025 increased $31.0 million compared to the three months ended September 30, 2024. The increase in research and development expenses was primarily attributable to an increase of $25.8 million in nomlabofusp manufacturing costs, an increase of $1.8 million in professional and consulting fees associated with ongoing clinical studies and increasing worldwide regulatory activities, an increase of $1.5 million in clinical costs primarily associated with the start of an anticipated confirmatory study that are required as part of an accelerated approval of our planned BLA submission expected in the second quarter of 2026, an increase of $1.0 million in personnel costs associated with increased headcount, and an increase of $0.9 million in non-clinical costs related to assay development.

General and Administrative expenses

General and administrative expenses for the three months ended September 30, 2025 increased $0.2 million compared to the three months ended September 30, 2024. The increase in general and administrative expenses was primarily due to an increase of $0.3 million of personnel costs associated with increased headcount and an increase of $0.2 million in professional fees primarily related to legal services performed. The increase was largely offset by a decrease of $0.2 million in stock compensation costs related to the full vesting of previously issued stock options granted at higher value stock options.

Other Income (expense), net

Other income (expense), net was $1.8 million income in the three months ended September 30, 2025 compared to $2.8 million income in the three months ended September 30, 2024. 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.

Comparison of nine months ended September 30, 2025 and 2024

The following table summarizes our results of operations for the nine months ended September 30, 2025 and 2024:

Research and development expenses for the nine months ended September 30, 2025 increased $48.3 million compared to the nine months ended September 30, 2024. The increase in research and development expenses was primarily attributable to an increase of $32.9 million in nomlabofusp manufacturing costs, an increase of $5.4 million in professional consulting fees associated with ongoing clinical studies and worldwide regulatory activities, an increase of $4.8 million in clinical costs primarily associated with initiating the anticipated confirmatory study required as part of an accelerated approval of our planned BLA submission expected in the second quarter of 2026, an increase of $3.9 million in personnel costs associated with increased quality and regulatory headcount and an increase of $1.7 million in nonclinical costs related to assay development, and partially offset by a decrease of $0.8 million in costs incurred under the TRACK-FA program.

General and Administrative expenses

General and administrative expenses for the nine months ended September 30, 2025 increased $0.6 million compared to the nine months ended September 30, 2024. The increase in general and administrative expenses was primarily due to an increase of $1.1 million of personnel costs associated with increased headcount (primarily commercial) and an increase of $0.5 million in professional service expenses primarily related to commercial start-up activities, partially offset by a decrease of $0.8 million in stock compensation costs related to the full vesting of previously issued stock options granted at higher value stock options.

Other Income (expense), net

Other income (expense), net was $5.3 million income in the nine months ended September 30, 2025 compared to $7.8 million income in the nine months ended September 30, 2024. 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

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 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.

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 nine months ended September 30, 2025, operating activities used $74.7 million of cash, resulting from our net loss of $103.2 million, adjusted for noncash expenses of $4.0 million and changes in our operating assets and liabilities resulting in a source of cash of $24.5 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 a increases in prepaid expenses, accounts payable, and accrued expenses.

During the nine months ended September 30, 2024, operating activities used $48.9 million of cash, resulting from our net loss of $51.8 million, adjusted for noncash expenses of $2.4 million and changes in our operating assets and liabilities resulting in a source of cash of $0.4 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 are primarily stock-based compensation expenses. The change in operating assets and liabilities was primarily due to an increase in accrued expenses and accounts payable, partially offset by a decrease in prepaid expense.

Net cash provided by (used in) investing activities

During the nine months ended September 30, 2025, investing activities provided $66.3 million. This source of cash resulted from the maturities of $150.0 million of marketable securities partially offset by purchases of $83.6 million of marketable securities.

During the nine months ended September 30, 2024, investing activities used $104.6 million. This net use of cash was due to the purchase of $189.2 million of marketable securities, partially offset by $85.0 million of cash provided by maturities of marketable securities.

Net cash provided by financing activities

During the nine months ended September 30, 2025, financing activities provided $65.3 million of cash flows from an offering of common stock.

During the nine months ended September 30, 2024, financing activities provided $161.8 million of cash flows primarily from an offering of common stock.

Operating Capital Requirements

We have not yet commercialized any products and do not expect to generate revenue from the commercial sale of any products for several years, if at all.

We have incurred net losses of approximately $103.2 million and $51.8 million for the nine months ended September 30, 2025 and 2024, respectively. As of September 30, 2025, we had an accumulated deficit of $372.3 million and cash, cash equivalents, and marketable securities of $175.4 million, excluding restricted cash of $0.6 million.

Losses have resulted principally from costs incurred in connection with research and development activities, and general and administrative costs associated with the development of nomlabofusp and our operations. 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.

We anticipate that current cash, cash equivalents, and marketable securities as of September 30, 2025 will fund operations into the fourth quarter of 2026. 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. Until we can generate substantial revenue, if ever, we expect to seek additional funding through a combination of public or private equity offerings, debt/royalty financings, collaborations, strategic alliances, licensing arrangements or other sources. The incurrence of indebtedness would result in increased fixed payment obligations and we may be required to agree to certain restrictive covenants, such as limitations on our ability to incur additional debt, minimum cash balances, limitations on our ability to acquire, sell or license intellectual property rights, and other operating restrictions that could adversely impact our ability to conduct our business. Any additional fundraising efforts may divert our management from their day-to-day activities, which may adversely affect our ability to develop and commercialize our product candidates.

There can be no assurance that we will be able to raise sufficient additional capital on acceptable terms, if at all. If such additional financing is not available on satisfactory terms, or is not available in sufficient amounts, or we do not have sufficient authorized shares, we may be required to delay, limit, or eliminate the development of business opportunities and our ability to achieve our business objectives, our competitiveness, and our business, financial condition, and results of operations will be materially adversely affected. We could also be required to seek funds through arrangements with collaborative partners, strategic alliances, or otherwise at an earlier stage than otherwise would be desirable and we may be required to relinquish rights to some of our technologies or product candidates or otherwise agree to terms unfavorable to us, any of which may have a material adverse effect on our business, operating results and prospects. In addition, geopolitical tensions including regional conflicts around the world, adverse macroeconomic events, including those due to inflationary pressures, rising interest rates, banking instability, monetary policy changes, changes in trade policies, including the current U.S. Government shutdown, tariffs (including tariffs and trade protection measures that have been or may in the future be imposed by the U.S. or other countries), new laws and regulations, including, but not limited to the recently enacted Public Law 119-21, economic slowdowns or recessions, health epidemics, unforeseen emergencies and other outbreaks of communicable diseases could disrupt our operations, the operations of third parties on which we rely, or the operations of regulatory agencies we interact with in the development of nomlabofusp and any other product candidates that we may develop which may reduce our ability to access capital, which could negatively affect our liquidity and ability to continue as a going concern.

If we are unable to obtain sufficient funding when needed and/or on acceptable terms, we may be required to significantly curtail, delay or discontinue one or more of our research and development programs, the manufacture of clinical and commercial supplies, product portfolio expansion and/or commercialization efforts, which could adversely affect our business prospects, or we may be unable to continue operations. Certain restrictive covenants, such as limitations on our ability to incur additional debt, limitations on our ability to acquire, sell, or license intellectual property rights and other operating restrictions that could adversely impact our ability to conduct our business. Any additional fundraising efforts may divert our management from their day-to-day activities, which may adversely affect our capability to develop and commercialize our product candidates.

Off-Balance Sheet Arrangements

During the periods presented, and through the date of this filing, we 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.