Quarterly Report for Quarter Ending September 30, 2025 (Form 10-Q)

Management's Discussion and Analysis ofFinancial Condition and Results of Operations.

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our unaudited condensed consolidated financial statements and related notes appearing elsewhere in this quarterly report on Form 10-Q and our audited financial statements and related notes for the year ended December 31, 2024 included in our annual report filed on Form 10-K on March 6, 2025.

Some of the statements contained in this discussion and analysis or set forth elsewhere in this quarterly report on Form 10-Q, including information with respect to our plans and strategy for our business, constitute forward looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). We have based these forward-looking statements on our current expectations and projections about future events. The following information and any forward-looking statements should be considered in light of factors discussed elsewhere in this quarterly report on Form 10-Q particularly including those risks identified in Part II, Item 1A "Risk Factors" and our other filings with the Securities and Exchange Commission (the "SEC").

Our actual results and timing of certain events may differ materially from the results discussed, projected, anticipated, or indicated in any forward-looking statements. We caution you that forward-looking statements are not guarantees of future performance and that our actual results of operations, financial condition and liquidity, and the development of the industry in which we operate may differ materially from the forward-looking statements contained in this quarterly report on Form 10-Q. Statements made herein are made as of the date of the filing of this Form 10-Q with the SEC and should not be relied upon as of any subsequent date. Even if our results of operations, financial condition and liquidity, and the development of the industry in which we operate are consistent with the forward-looking statements contained in this quarterly report on Form 10-Q, they may not be predictive of results or developments in future periods. We disclaim any obligation, except as specifically required by law and the rules of the SEC, to publicly update or revise any such statements to reflect any change in our expectations or in events, conditions or circumstances on which any such statements may be based or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

We caution readers not to place undue reliance on any forward-looking statements made by us, which speak only as of the date they are made.

Overview

We are a life sciences company focused on advancing a portfolio of current and future gene therapy candidates, which we refer to collectively as our Candidates, including SGT-003 for the treatment of Duchenne muscular dystrophy ("Duchenne"), SGT-212 for the treatment of Friedreich's ataxia ("FA"), SGT-501 for the treatment of catecholaminergic polymorphic ventricular tachycardia ("CPVT"), SGT-601 for the treatment of TNNT2-mediated dilated cardiomyopathy ("TNNT2 DCM"), and additional assets for the treatment of genetic cardiac and neuromuscular diseases, at different stages of development, with varying levels of investment. We are advancing our diverse pipeline across rare neuromuscular and cardiac diseases, bringing together experts in science, technology, disease management and care. Patient-focused and founded by those directly impacted by Duchenne, our mission is to improve the daily lives of patients living with these devastating diseases.

Solid was purpose-built to advance the best science and accelerate the discovery and development of treatments that may benefit all patients with Duchenne. As we expand to bring meaningful treatments to patients living with other neuromuscular and cardiac diseases, the values and guiding principles that drive us continue. Our corporate vision is to build an innovation platform enabling the discovery and development of high-value genetic medicines for neuromuscular and cardiac diseases by integrating internal capabilities, including a vector core, use of validated animal models, optimized expression cassettes, novel capsids and regulatory expertise, and collaborations with leaders in related clinical and research fields. Our mission, which guides our operations, is to treat and change the course of neuromuscular and cardiac diseases at all stages. Underscoring this mission, our disease-focused business model is founded on the following fundamental principles:

We are continuing to advance our pipeline of Candidates. The U.S. Food and Drug Administration (the "FDA") has granted Fast Track, Orphan Drug, and Rare Pediatric Disease designations for SGT-003 for Duchenne and SGT-003 has also been awarded an Innovation Passport by the new UK Innovative Licensing and Access Pathway. The FDA has granted Fast Track and Rare Pediatric Disease designations for SGT-212 for the treatment of FA. The FDA has granted Fast Track, Orphan Drug and Rare Pediatric Disease designations to SGT-501 for the treatment of CPVT.

As we continue to pursue opportunities in both the U.S. and international markets, we remain attentive to evolving global economic conditions, including uncertainties related to international trade policies, tariffs, and supply chain dynamics. Although these factors have not had a material impact on our operations to date, future changes in trade regulations, tariff structures, or logistical constraints could influence the cost, availability, or timing of materials and components used in our manufacturing processes. We continue to monitor these developments closely.

SGT-003

Participant dosing in the Phase 1/2 INSPIRE DUCHENNE trial of SGT-003 began in the second quarter of 2024. The INSPIRE DUCHENNE trial is a Phase 1/2 first-in-human, open-label, single-dose, multicenter trial designed to evaluate the safety, tolerability and efficacy of SGT-003 in pediatric participants with Duchenne at a dose of 1E14vg/kg. SGT-003 is administered as a one-time intravenous infusion. In September 2024 and June 2025, we amended the INSPIRE DUCHENNE clinical trial protocol to increase the anticipated participant enrollment size, expand the participant cohort age groups, and extend the timepoints of certain secondary objective measurements. In connection with the expanded clinical trial, we have initiated work for additional GMP batches of SGT-003.

On November 3, 2025, we announced positive interim data from the Phase 1/2 INSPIRE DUCHENNE trial as of the data cutoff date of September 29, 2025. Interim biopsy data reported from 10 participants treated with SGT-003 showed a mean microdystrophin expression of 58%, as measured by both western blot and mass spectrometry, and mean microdystrophin positive fibers of 51%, as measured by immunofluorescence. Interim data also demonstrated early signals of cardiac function normalization and improvements in multiple biomarkers that are indicators of muscle integrity, health and resilience. These interim data include favorable reductions across a range of biomarkers of muscle injury and breakdown, including serum creatine kinase (CK), serum alanine transaminase (ALT), serum aspartate aminotransferase (AST), serum lactate dehydrogenase (LDH) and serum titin, through both Day 90 and Day 360 after treatment with SGT-003. Additionally, following treatment with SGT-003, we observed restoration of key components of the dystrophin associated protein complex (DAPC), including beta-sarcoglycan and neuronal nitric oxide synthase (nNOS), and early signals of a potential for cardiac benefit through reduction in troponin I (cTnI) and increased systolic function as measured by LVEF by echocardiography.

As of October 31, 2025, 23 participants have been dosed in the INSPIRE DUCHENNE trial and SGT-003 has been generally well tolerated as of such date. There has been one treatment-related serious adverse event reported in the INSPIRE DUCHENNE trial. This serious adverse event was identified as a Grade 3 immune-mediated myositis which, importantly, was not associated with muscle pain or weakness, and occurred in a participant who had a large deletion in a region coded for by SGT-003's microdystrophin. The study participant promptly responded to steroid treatment with all clinical symptoms noted at presentation resolving and with muscle biomarkers, including CK, declining well below baseline levels. This SAE was reviewed by the data and safety monitoring board (DSMB) with the recommendation to continue dosing without interruption.

For a more detailed description of the interim results from the INSPIRE DUCHENNE trial, see our Form 8-K filed November 3, 2025.

Enrollment and dosing in the INSPIRE DUCHENNE trial is ongoing, with 30 total participants anticipated to be dosed by early 2026.

The INSPIRE DUCHENNE trial currently has 15 active sites across the U.S., Canada, Italy and the United Kingdom, with an additional site expected to be activated by the end of 2025. A meeting with the FDA to discuss potential regulatory pathways, including accelerated approval pathways, for SGT-003 is anticipated to occur in the first half of 2026.

Additionally, in October 2025, we activated the first clinical trial site and began screening participants for IMPACT DUCHENNE, a Phase 3 randomized, double-blind, placebo-controlled trial evaluating SGT-003 outside of the United States. IMPACT DUCHENNE has been designed with the aim of supporting potential ex-U.S. regulatory authorizations. We have received regulatory approvals to conduct IMPACT DUCHENNE in both Canada and Australia, and we plan to expand the trial into additional countries, subject to receipt of regulatory approval.

The FDA has granted Fast Track, Orphan Drug, and Rare Pediatric Disease designations for SGT-003 for the treatment of Duchenne. SGT-003 has been awarded an Innovation Passport by the new UK Innovative Licensing and Access Pathway, which aims to accelerate time to market and facilitate patient access to new medicines in the United Kingdom.

SGT-212

In January 2025, we announced that the FDA cleared our investigational new drug ("IND") for SGT-212 for the treatment of FA. In October 2025, we activated the first clinical trial site and began screening participants for FALCON, an open-label, multi-center Phase 1b clinical trial of SGT-212. The trial is expected to enroll non-ambulatory and ambulatory adult participants living with FA in up to three cohorts and is designed to evaluate the safety and tolerability of systemic and bilateral intradentate nucleus administration of SGT-212. The FDA has granted Fast Track and Rare Pediatric Disease designations to SGT-212 for the treatment of FA.

SGT-501

In July 2025, we announced that the FDA cleared our IND and that Health Canada approved our clinical trial application ("CTA") for SGT-501 for the treatment of CPVT. We anticipate activating the first clinical trial site for ARTEMIS, an open-label, multi-center Phase 1b clinical trial of SGT-501 in adult participants with CPVT in the fourth quarter of 2025. The FDA has granted Fast Track, Orphan Drug and Rare Pediatric Disease designations to SGT-501 for the treatment of CPVT.

Other Cardiac Programs

We are currently developing a preclinical product candidate, SGT-601, for the treatment of TNNT2 DCM. Efficacy studies in mice suggest that SGT-601 treatment resulted in a restoration of ejection fraction function and a stabilization in cardiac function over time.

Capsids

AAV-SLB101, Solid's proprietary, rationally designed capsid used in SGT-003, has been generally well tolerated as of October 31, 2025 (N=23), in the INSPIRE DUCHENNE trial as well as in non-human primates ("NHP") and mouse studies.

We are focused on developing transformative treatments to improve the lives of patients with rare neuromuscular and cardiac diseases. The majority of our current programs are designed to treat these diseases with gene transfer products. Gene transfer, a type of gene therapy, is designed to address diseases caused by mutated genes through the delivery of functional versions of genes, called transgenes. The transgenes are then utilized by the body to produce desired proteins that act therapeutically to treat the condition. In addition to a transgene, our gene transfer Candidates include a viral capsid or vector (a protein shell utilized as a vehicle to deliver a transgene to cells in the body) and a promoter (a specialized DNA sequence that directs cells to produce the protein in specific tissues). The capsid is modified to no longer self-replicate yet still retains its ability to introduce new genetic material directly into patients' cells. Adeno-associated virus ("AAV") capsids have been approved for use to deliver transgenes to patients, including via systemic delivery as well as stereotactic neurosurgical administration to the brain. The use of AAV capsids to deliver gene therapies has also been extensively studied by third parties in human clinical trials for multiple disease indications, and in certain of these trials AAV was delivered systemically to the participant.

We are building multiple cardiac and neuromuscular next-generation capsid and promoter libraries with final capsid selection from the first cardiac capsid library anticipated in the first half of 2026.

Our Operations

Due to our significant research and development expenditure, licensing and patent investment, and general and administrative costs associated with our operations, we have generated substantial operating losses in each period since our inception. Our net losses were $45.8 million and $124.5 million for the three and nine months ended September 30, 2025, respectively, and $32.7 million and $82.1 million for the three and nine months ended September 30, 2024, respectively. As of September 30, 2025, we had an accumulated deficit of $908.0 million. We expect to incur significant expenses and operating losses for the foreseeable future.

As we seek to develop and commercialize our Candidates, we anticipate that our expenses will increase significantly and that we will need substantial additional funding to support our continuing operations. Until such time as we can generate significant revenue from product sales, if ever, we expect to finance our operations through a combination of public or private equity financing, debt financings or other sources, which may include licensing agreements or strategic collaborations. We may be unable to raise additional funds or enter into such agreements or arrangements when needed on favorable terms, if at all. If we fail to raise capital or enter into such agreements as and when needed, we may have to significantly delay, scale back or discontinue the development or commercialization of our Candidates.

Because of the numerous risks and uncertainties associated with product development, we are unable to predict the timing or amount of increased expenses or determine when or if we will be able to achieve or maintain profitability. Even if we are able to generate revenue from product sales, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations.

As of September 30, 2025, we had cash, cash equivalents, and available-for-sale securities of $236.1 million, excluding restricted cash of $1.9 million. We believe that our cash, cash equivalents, and available-for-sale securities as of September 30, 2025 will enable us to fund our operating expenses and capital expenditure requirements into the first half of 2027. We have based this estimate on assumptions that may prove to be wrong, and we could use our available capital resources sooner than we currently anticipate.

Financial Operations Overview

Revenue

We have not generated any commercial product revenue to date and do not expect to generate any product revenue from the sale of our products for the foreseeable future, if ever. If our development efforts for our Candidates are successful and result in marketing approval, we may generate commercial product revenue in the future.

Operating Expenses

We classify our operating expenses into two categories: research and development and general and administrative expenses. Personnel costs, including salaries, benefits, bonuses, and equity-based compensation expense comprise a significant component of both expense categories. We allocate expenses associated with personnel costs based on the nature of work associated with these resources.

Research and Development Expenses

Research and development expenses consist primarily of costs incurred for our research activities, including our discovery efforts, and clinical and preclinical development activities for our Candidates and include:

Research and development activities are central to our business model. We are still in the early stages of development of our Candidates. Candidates in later stages of clinical development generally have higher development costs than those in preclinical development or in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials. We expect that our research and development expenses will continue to increase for the foreseeable future if and as we continue to conduct clinical trials for SGT-003 and SGT-212, initiate clinical trials for our other Candidates, including our planned ARTEMIS trial of SGT-501, and continue to identify and develop additional Candidates.

We typically use our employee and infrastructure resources across our Candidates. We track outsourced development costs and milestone payments made under our licensing arrangements by Candidate, but we do not allocate personnel costs, license payments made under our licensing arrangements or other internal costs to Candidates on a program-specific basis. These costs are included in unallocated research and development expenses in the table below.

The following table summarizes our research and development expenses by Candidate for the respective periods (in thousands):

We cannot determine with certainty the duration, costs, and timing of ongoing and planned clinical trials of SGT-003, SGT-212, SGT-501 or our other Candidates, or if, when, or to what extent we will generate revenue from the commercialization and sale of any of our Candidates for which we obtain marketing approval or our other research and development expenses. We may never succeed in obtaining marketing approval for any of our Candidates. The duration, costs, and timing of clinical trials and development of our Candidates will depend on a variety of factors, including:

General and Administrative Expenses

General and administrative expenses consist primarily of salaries and other related costs, including equity-based compensation, for personnel in our executive, finance, business development and administrative functions. General and administrative expenses also include legal fees relating to patent and corporate matters, professional fees for accounting, auditing, tax and consulting services, insurance costs, travel expenses, and facility-related expenses.

We expect that our general and administrative expenses will increase in the future as we support our research and development activities and activities related to our INSPIRE DUCHENNE trial, our IMPACT DUCHENNE trial, our FALCON trial, our planned ARTEMIS trial of SGT-501, and any other planned or future clinical trials for and potential commercialization of our Candidates.

Other Income, Net

Other income, net consists primarily of interest income. Interest income consists of income earned on our cash and cash equivalents, available-for-sale securities, and restricted cash.

Critical Accounting Policies and Use of Estimates

Our management's discussion and analysis of our financial condition and results of operations is based on our condensed consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States. The preparation of our condensed consolidated financial statements and related disclosures requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, costs and expenses and the disclosure of contingent assets and liabilities in our condensed consolidated financial statements. We base our estimates on historical experience, known trends and events and various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about

the carrying values of assets and liabilities that are not readily apparent from other sources. We evaluate our estimates and assumptions on an ongoing basis. Our actual results may differ materially from these estimates.

During the nine months ended September 30, 2025, there were no material changes to our critical accounting policies. Our critical accounting policies are described under the heading "Management's Discussion and Analysis of Financial Condition and Results of Operations-Critical Accounting Policies and Use of Estimates" in our Annual Report on Form 10-K for the year ended December 31, 2024 and the notes to the unaudited condensed consolidated financial statements included in Part I, Item 1, "Financial Statements (unaudited)," of this Quarterly Report on Form 10-Q. We believe that of our critical accounting policies, the following accounting policies involve the most judgment and complexity:

Accordingly, we believe the policies set forth above are critical to fully understanding and evaluating our financial condition and results of operations. If actual results or events differ materially from the estimates, judgments and assumptions used by us in applying these policies, our reported financial condition and results of operations could be materially affected.

Results of Operations

Comparison of the Three Months Ended September 30, 2025 and 2024

The following table summarizes our results of operations for the periods indicated (in thousands, except percentages):

Research and Development Expenses

The following table summarizes our research and development expenses by Candidate for the periods indicated (in thousands, except percentages):

Research and development expenses for the three months ended September 30, 2025 were $38.9 million, compared to $27.3 million for the three months ended September 30, 2024. The increase of $11.5 million in research and development expenses was primarily due to a $12.8 million increase in costs for SGT-003 primarily related to manufacturing, regulatory, and clinical costs, a $2.7 million increase in personnel related expenses, and a $0.9 million increase in costs for SGT-601 primarily related to manufacturing and research costs, partially offset by a $3.3 million decrease in costs for SGT-212 primarily related to lower license and milestone related costs partially offset by an increase in clinical costs, and a $1.8 million decrease in in costs for SGT-501 primarily related to lower research and manufacturing costs.

General and Administrative Expenses

General and administrative expenses were $9.2 million for the three months ended September 30, 2025, compared to $7.9 million for the three months ended September 30, 2024. The increase of $1.3 million was primarily related to a $0.9 million increase in personnel related costs and a $0.4 million increase in legal and consulting fees.

Other Income, Net

Other income, net was $2.3 million for the three months ended September 30, 2025 compared to $2.5 million for the three months ended September 30, 2024. The decrease of $0.2 million was primarily related to the change in fair value of derivative liabilities.

Comparison of the Nine Months Ended September 30, 2025 and 2024

The following table summarizes our results of operations for the periods indicated (in thousands, except percentages):

Research and Development Expenses

The following table summarizes our research and development expenses by Candidate for the periods indicated (in thousands, except percentages):

Research and development expenses for the nine months ended September 30, 2025 were $102.2 million, compared to $65.7 million for the nine months ended September 30, 2024. The increase of $36.5 million in research and development expenses was primarily

due to a $30.1 million increase in costs for SGT-003 primarily related to manufacturing and clinical costs, a $7.0 million increase in personnel related expenses, a $4.9 million increase in costs for SGT-601 primarily related to manufacturing and research costs, partially offset by a $2.3 million decrease in costs for SGT-501 primarily related to lower manufacturing and study costs partially offset by an increase in clinical, regulatory and licensing fees, a $2.1 million decrease in other development programs primarily related to lower research and manufacturing costs, and a $1.5 million decrease in costs for SGT-212 primarily related to lower license and milestone payments partially offset by an increase in clinical, regulatory, and research costs.

General and Administrative Expenses

General and administrative expenses were $27.6 million for the nine months ended September 30, 2025, compared to $24.2 million for the nine months ended September 30, 2024. The increase of $3.4 million was primarily related to a $3.7 million increase in personnel related costs and a $0.3 million increase in equipment costs, partially offset by a $0.3 million decrease in recruiting fees.

Other Income, Net

Other income, net was $5.3 million for the nine months ended September 30, 2025 compared to $7.7 million for the nine months ended September 30, 2024. The decrease of $2.5 million was primarily related to the change in fair value of derivative liabilities.

Liquidity and Capital Resources

Sources of Liquidity

To date, we have financed our operations primarily through the sale of redeemable preferred units and member units, the sale of securities in private placements and follow-on offerings, the sale of common stock in our initial public offering, and sales of common stock under our "at-the-market offering" sales agreement with Jefferies LLC ("Jefferies") (the "ATM Sales Agreement"). Through September 30, 2025, we raised an aggregate of $144.6 million of gross proceeds from our sales of preferred units prior to the completion of our initial public offering, and an aggregate of $858.5 million of net proceeds from the sale of our common stock through public offerings, including our IPO and follow-on public offerings, private placements, the ATM Sales Agreement, and pursuant to the stock purchase agreements.

On March 13, 2019, we entered into the ATM Sales Agreement, which was amended and restated in March 2024, under which we may offer and sell, from time to time, shares of our common stock through Jefferies as sales agent. Any such sales being made by any method that is deemed an "at-the-market offering" as defined in Rule 415 promulgated under the Securities Act. We will pay Jefferies a commission of up to 3% of the gross proceeds of any sales of common stock pursuant to the ATM Sales Agreement. During the year ended December 31, 2024, we sold 2,212,937 shares pursuant to the ATM Sales Agreement resulting in net proceeds of $18.4 million. During three and nine months ended September 30, 2025, we sold 236,616 and 298,158 shares pursuant to the ATM Sales Agreement resulting in net proceeds of $1.4 million and $1.7 million, respectively.

On January 11, 2024, we issued and sold 16,973,103 shares of our common stock at a price per share of $5.53 and, to one investor in lieu of shares of common stock, pre-funded warrants to purchase 2,712,478 shares of common stock at a price of $5.529 per pre-funded warrant, in a private placement we refer to as the January 2024 Private Placement. We received $103.7 million of net proceeds from the January 2024 Private Placement after deducting offering costs.

On February 19, 2025, we issued and sold in an underwritten offering (the "February 2025 Offering"), 35,739,810 shares of our common stock at a price of $4.03 per share and, to certain investors in lieu of shares of common stock, pre-funded warrants to purchase 13,888,340 shares of common stock at a price of $4.029 per pre-funded warrant. We received approximately $188.0 million of net proceeds from the February 2025 Offering, after deducting underwriting discounts and commissions and offering costs.

As of September 30, 2025, we had cash, cash equivalents, and available-for-sale securities of $236.1 million, excluding restricted cash of $1.9 million, and had no debt outstanding.

Summary of Cash Flows

The following table summarizes our sources and uses of cash for each of the periods presented (in thousands):

Operating Activities

During the nine months ended September 30, 2025, operating activities used $102.7 million of cash, primarily resulting from our net loss of $124.5 million partially offset by changes in our operating assets and liabilities of $6.4 million and non-cash charges of $15.4 million. Net cash used by changes in our operating assets and liabilities during the nine months ended September 30, 2025 consisted of an increase in prepaid expenses and other assets of $0.3 million, and a decrease in the operating lease liability of $1.3 million, offset by an increase in accounts payable of $4.2 million, and an increase in accrued expenses and other liabilities of $3.9 million. Non-cash activities were driven by equity-based compensation of $10.4 million, a change in the fair value of derivative liabilities of $3.4 million, non-cash lease expense of $1.8 million, depreciation and amortization expense of $1.2 million, partially offset by amortization of available-for-sale securities of $1.1 million.

During the nine months ended September 30, 2024, operating activities used $70.4 million of cash, primarily resulting from our net loss of $82.1 million partially offset by changes in our operating assets and liabilities of $0.7 million and non-cash charges of $11.0 million. Net cash used by changes in our operating assets and liabilities during the nine months ended September 30, 2024 consisted of an increase of $2.5 million in prepaid and other assets, and a decrease in the operating lease liability of $1.3 million, offset by an increase in accrued expenses and other liabilities of $3.1 million, and an increase in accounts payable of $1.4 million. Non-cash activities were driven by equity-based compensation of $6.7 million, depreciation and amortization expense of $2.0 million, non-cash lease expense of $1.8 million, and a change in the fair value of derivative liabilities of $3.4 million, partially offset by amortization of available-for-sale securities of $2.8 million.

Investing Activities

During the nine months ended September 30, 2025, investing activities used $105.5 million of cash, resulting from the purchases of available-for sale securities of $212.0 million and the purchases of property plant and equipment of $0.6 million, partially offset by the maturity of available-for sale securities of $107.0 million.

During the nine months ended September 30, 2024, investing activities used $54.7 million of cash, resulting from the purchases of available-for sale securities of $189.0 million and the purchases of property plant and equipment of $0.5 million, partially offset by the maturity of available-for sale securities of $134.8 million.

Financing Activities

During the nine months ended September 30, 2025, financing activities provided $189.3 million of cash, resulting from the net proceeds from the issuance and sale of common stock and pre-funded warrants to purchase shares of common stock of $189.6 million, and proceeds from the issuance of shares of $0.2 million under our Amended and Restated 2021 Employee Stock Purchase Plan, or ESPP, offset by payments of the principal portion of finance lease obligations of $0.5 million.

During the nine months ended September 30, 2024, financing activities provided $115.5 million of cash, resulting from the net proceeds from the issuance of common stock and pre-funded warrants to purchase shares of common stock of $115.3 million, proceeds from the exercise of common stock options for $0.4 million, and proceeds from the issuance of shares of $0.1 million under the ESPP, offset by payments of the principal portion of finance lease obligations of $0.3 million.

Funding Requirements

We expect our expenses to increase substantially in connection with our ongoing development activities related to our Candidates. In addition, we have incurred and expect to continue to incur costs associated with operating as a public company. We expect that our expenses will increase substantially if and as we:

As of September 30, 2025, we had cash, cash equivalents and available-for-sale securities of $236.1 million, excluding restricted cash of $1.9 million. Based on our current operating plan, we believe that our cash, cash equivalents and available-for-sale securities as of September 30, 2025 will be sufficient to fund our operating expenses and capital requirements into the first half of 2027. As a result, in order to continue to operate our business beyond that time, we will need to raise additional funds. However, there can be no assurance that we will be able to generate funds on terms acceptable to us, on a timely basis, or at all. In addition, we have based this estimate on assumptions that may prove to be wrong, and we could use our available capital resources sooner than we currently anticipate.

Due to the numerous risks and uncertainties associated with the development of our Candidates and because the extent to which we may enter collaborations with third parties for development of our Candidates is unknown, we are unable to estimate the timing and amounts of increased capital outlays and operating expenses associated with completing the research and development of our Candidates. Our future capital requirements will depend on many factors, including:

We are supplying, and expect to continue to supply, our ongoing and future preclinical and clinical development programs with drug product produced at a cGMP compliant facility located at one of our CDMOs. We intend to establish the capability and capacity to supply Candidates at commercial scale from multiple sources.

Developing pharmaceutical products, including conducting preclinical studies and clinical trials, is a time-consuming, expensive and uncertain process that takes years to complete, and we may never generate the necessary data or results required to obtain marketing approval for any Candidates or generate revenue from the sale of any products for which we may obtain marketing approval. In addition, our Candidates, if approved, may not achieve commercial success. Our commercial revenues, if any, will be derived from sales of products that we do not expect to be commercially available for many years, if ever. Accordingly, we will need to obtain substantial additional funds to achieve our business objectives.

Adequate additional funds may not be available to us on acceptable terms, or at all. We do not currently have any committed external source of funds. To the extent that we raise additional capital through the sale of equity securities, our existing stockholders'

ownership interest may be diluted. Any debt or preferred equity financing, if available, may involve agreements that include restrictive covenants that may limit our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends, which could adversely impact our ability to conduct our business, and may require the issuance of warrants, which could potentially dilute existing stockholders' ownership interests.

If we raise additional funds through licensing agreements and strategic collaborations with third parties, we may have to relinquish valuable rights to our technology, future revenue streams, research programs, or Candidates or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds, we may be required to delay, limit, reduce and/or terminate development of our Candidates or any future commercialization efforts or grant rights to develop and market Candidates that we would otherwise prefer to develop and market ourselves.

Contractual Obligations and Commitments

During the nine months ended September 30, 2025, there were no material changes to our contractual obligations and commitments from those described in "Management's Discussion and Analysis of Financial Condition and Results of Operations" in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024.

Recently Issued Accounting Pronouncements

A summary of significant recent accounting pronouncements that we expect to adopt is included in Note 1 - Nature of the Business and Basis of Presentation to our condensed consolidated financial statements (See Part I, Item 1 - Financial Statements, of this Quarterly Report on Form 10-Q).

Off-Balance Sheet Arrangements

We did not have during the periods presented, and we do not currently have, any off-balance sheet arrangements, as defined in the rules and regulations of the SEC.