Quarterly Report for Quarter Ending March 31, 2025 (Form 10-Q)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-Q

(Mark One)

For the quarterly period ended March 31, 2025

OR

For the transition period from to

Commission File Number: 001-39527

PRELUDE THERAPEUTICS INCORPORATED

(Exact Name of Registrant as Specified in its Charter)

Registrant's telephone number, including area code: (302) 467-1280

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

As of April 30, 2025, the registrant had 56,460,481shares of voting and non-voting common stock, $0.0001 par value per share, outstanding.

Table of Contents

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PART I-FINANCIAL INFORMATION

Item 1. Financial Statements.

PRELUDE THERAPEUTICS INCORPORATED

BALANCESHEETS

See accompanying notes to unaudited interim financial statements.

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PRELUDE THERAPEUTICS INCORPORATED

STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(UNAUDITED)

See accompanying notes to unaudited interim financial statements.

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PRELUDE THERAPEUTICS INCORPORATED

STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY

(UNAUDITED)

See accompanying notes to unaudited interim financial statements.

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PRELUDE THERAPEUTICS INCORPORATED

STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (CONTINUED)

(UNAUDITED)

See accompanying notes to unaudited interim financial statements.

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PRELUDE THERAPEUTICS INCORPORATED

STATEMENTS OF CASH FLOWS

(UNAUDITED)

See accompanying notes to unaudited interim financial statements.

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PRELUDE THERAPEUTICS INCORPORATED

NOTES TO UNAUDITED INTERIM FINANCIAL STATEMENTS

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3. Summary of significant accounting policies

The complete summary of significant accounting policies included in the Company's financial statements for the year ended December 31, 2024 can be found in "Note 3. Summary of significant accounting policies" of the Company's Annual Report on Form 10-K filed with the Securities and Exchange Commission (the "SEC") on March 10, 2025.

Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company's chief operating decision maker ("CODM") is its Chief Executive Officer. The Company views and manages its operations as a singleoperating segment.

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assets for accounting purposes. Costs incurred by the Company related to tenant improvements in excess of the landlord's allowance were treated as prepaid rent and increased the right-of-use asset on the commencement date.

In April 2024, the Company entered into a 12 month finance lease for equipment.

Our operating lease costs for each of the three months ended March 31, 2025and 2024 were $1.1million. Supplemental balance sheet and other information related to our operating and finance leases as of March 31, 2025 and December 31, 2024 were as follows:

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The Company paid a security deposit for the Chestnut Run Lease in the form of a letter of credit of $4.0million, which is included in the accompanying balance sheet as restricted cash as of March 31, 2025. The security deposit may be reduced to $0.5million over time in accordance with the terms of the Chestnut Run Lease. The Company expects the letter of credit to be reduced to $3.2million in 2025.

Employment Agreements

The Company has employment agreements with key personnel providing for compensation and severance in certain circumstances, as defined in the respective employment agreements.

401(k) Defined Contribution Plan

The Company sponsors a 401(k) defined-contribution plan covering all employees. Participants are permitted to contribute up to 100% of their eligible annual pretax compensation up to an established federal limit on aggregate participant contributions. The Company provides a match of a maximum amount of 3% of the participant's compensation. For each of the three months ended March 31, 2025 and 2024, the Company made matching contributions of $0.2million.

Research Collaboration Agreement

In 2023, the Company entered into a multi-year, multi-program agreement with AbCellera Biologics Incorporated ("AbCellera") to jointly discover, develop, and commercialize novel oncology medicines for up to five programs. Under the terms of the agreement, AbCellera will lead manufacturing activities and the Company will lead clinical development and global commercialization, subject to AbCellera's option to co-promote any resulting commercial products in the United States. If, at any point one party in the collaboration opts-out of future co-development cost sharing, that party will be entitled to a royalty from commercialization of the collaboration target, dependent on the proportion of their co-development contributions compared to the total development costs of a target as defined within the agreement. The Company concluded that the agreement with AbCellera will be accounted for under the scope of ASC 808, Collaborative Arrangements, as both parties will actively participate in joint operating activities and are exposed to significant risks and rewards. Under ASC 808, certain transactions between collaborative arrangement participants should follow the accounting for revenue under ASC 606, Revenue from Contracts with Customers, when the collaborative arrangement participant is a customer for a distinct good or service. The Company determined that co-development arrangement as defined in our agreement with AbCellera does not meet the definition of a customer as defined by ASC 606. As a result, these activities will be accounted for as research and development costs. Costs related to the AbCellera collaboration were not material for the three months ended March 31, 2025 and 2024.

License Agreement

In May 2024, the Company and Pathos AI, Inc. ("Pathos") entered into a license agreement under which the Company granted to Pathos an exclusive, sublicensable, world-wide license to its selective, brain-penetrant PRMT5 inhibitor, PRT811. Under the terms of the license agreement, the Company received a $3.0million upfront, non-refundable payment. The agreement also included a near term $4.0million payment upon the earlier of 180 days following the effective date of the license agreement or the execution of a quality agreement between the parties pursuant to which the Company transferred title to certain quantities of Active Pharmaceutical

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10. Stock-Based Compensation

The Company has twoequity incentive plans: the 2016 Equity Incentive Plan, as amended, and the 2020 Equity Incentive Plan. New awards can only be granted under the 2020 Equity Incentive Plan (the "Plan") and as of March 31, 2025, 5,414,154shares were available for future grants. The number of shares of the Company's common stock that may be issued pursuant to rights granted under the Plan shall automatically increase on January 1st of each year and continuing for ten yearsbeginning on January 1, 2021, in an amount equal to fivepercent of the total number of shares of the Company's common stock outstanding on December 31st of the preceding calendar year, subject to the discretion of the Company's board of directors or compensation committee to determine a lesser number of shares shall be added for such year. On January 1, 2025, 2,757,455shares were added to the Plan.The Plan provides for the granting of common stock, incentive stock options, nonqualified stock options, restricted stock awards, restricted stock units and/or stock appreciation rights to employees, directors, and other persons, as determined by the Company's board of directors. The Company's stock options vest based on the terms in each award agreement, generally over four-yearperiods with 25% of options vesting after one yearand then monthly thereafter, and have a term of ten years.

The Company measures stock-based awards at their grant-date fair value and records compensation expense on a straight-line basis over the vesting period of the awards. The Company recorded stock-based compensation expense in the following expense categories in its accompanying statements of operations:

Stock Options

At March 31, 2025, the aggregate intrinsic value of both outstanding options and exercisable options was $6thousand.

The weighted-average grant date fair value of options granted was $1.11and $3.40per option for the three months ended March 31, 2025 and 2024, respectively. The Company recorded stock-based compensation expense of $3.7million and $5.3million

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for the three months ended March 31, 2025 and 2024, respectively, related to stock options. As of March 31, 2025, the total unrecognized compensation expense related to unvested stock option awards was $20.5million, which the Company expects to recognize over a weighted-average period of 2.18years.

Restricted Stock Units

The Company granted restricted stock units ("RSU") to employees that generally vest over a four-yearperiod with 25% of awards vesting after one year and then quarterly thereafter. Any unvested units will be forfeited upon termination of services.

The Company recorded stock-based compensation expense of $0.1million for both the three months ended March 31, 2025 and 2024, related to RSUs. At March 31, 2025, the total unrecognized expense related to the RSUs was $0.5million, which the Company expects to recognize over 2.92years.

Employee Stock Purchase Plan

The Company has an Employee Stock Purchase Plan (the "ESPP"), which, as of March 31, 2025, had 2,527,061shares of common stock reserved for future issuance. The number of shares of the Company's common stock that may be issued pursuant to rights granted under the ESPP shall automatically increase on January 1st of each year and continuing for ten yearsbeginning in 2021, in an amount equal to onepercent of the total number of shares of all classes of the Company's common stock outstanding on December 31st of the preceding calendar year, subject to the discretion of the Company's board of directors or compensation committee to determine a lesser number of shares shall be added for such year.On January 1, 2025, 551,491shares were added to the ESPP.

Under the ESPP, eligible employees can purchase the Company's common stock through accumulated payroll deductions at such times as are established by the Company's compensation committee. Eligible employees may purchase the Company's common stock at 85% of the lower of the fair market value of the Company's common stock on the first day of the offering period or on the last day of the offering period. Eligible employees may contribute up to 15% of their eligible compensation. Under the ESPP, a participant may not accrue rights to purchase more than $25,000worth of the Company's common stock for each calendar year in which such right is outstanding.

The ESPP is considered compensatory under the FASB stock compensation rules. Accordingly, share-based compensation expense is determined based on the option's grant-date fair value as estimated by applying the Black Scholes option-pricing model and is recognized over the withholding period. The Company recognized share-based compensation expense of $40thousand and $60thousand, respectively, for the three months ended March 31, 2025 and 2024related to the ESPP.

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Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations.

You should read the following discussion and analysis of our financial condition and results of operations together with our financial statements and the related notes and other financial information included elsewhere in this Quarterly Report on Form 10-Q. In addition to historical financial information, this discussion contains forward-looking statements based upon current expectations that involve risks and uncertainties, such as statements of our plans, objectives, expectations, intentions and belief. Our actual results could differ materially from those anticipated in these forward-looking statements as a result of various factors, including those set forth in the section titled "Risk Factors" under Part I, Item 1A of our Annual Report on Form 10-K filed with the SEC on March 10, 2025, or our 2024 Annual Report on Form 10-K. These forward-looking statements may include, but are not limited to, statements regarding our future results of operations and financial position, our ability to develop our clinical candidates, inflation and interest rate risk, a potential recession, a potential temporary federal government shutdown, business strategy, market size, potential growth opportunities, preclinical and clinical development activities, efficacy and safety profile of our product candidates, use of net proceeds from our offerings, our ability to maintain and recognize the benefits of certain designations received by product candidates, the timing and results of preclinical studies and clinical trials, commercial collaborations with third parties and the receipt and timing of potential regulatory designations, approvals and commercialization of product candidates. The words "believes," "anticipates," "estimates," "plans," "expects," "intends," "may," "could," "should," "potential," "likely," "projects," "continue," "will," "schedule," and "would" and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

These statements are based upon information available to us as of the date of this Quarterly Report on Form 10-Q, and while we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted an exhaustive inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain, and investors are cautioned not to unduly rely upon these statements.

Overview

Prelude is a clinical-stage precision oncology company built on a foundation of drug discovery excellence to deliver novel precision cancer medicines to underserved patients. By leveraging our core competencies in cancer biology and medicinal chemistry, combined with our clinical development capabilities, we have built an efficient, drug discovery engine and the development expertise necessary to identify compelling biological targets and create new chemical entities, or NCEs, that we advance into clinical trials. We believe our approach could result in better targeted cancer therapies. Our discovery excellence has been supported by our steady progress in creating a wholly-owned, internally developed pipeline. We also are working with our partner AbCellera Biologics Incorporated ("AbCellera") on an early-stage discovery program involving potent degraders as payloads for novel antibodies targeting tumor specific antigens. Since our inception in 2016, we have received clearance from the U.S. Food and Drug Administration, or the FDA, for multiple investigational new drug applications, or INDs, and successfully advanced several programs into clinical trials. In addition, we have other differentiated proprietary programs in various stages of preclinical development.

By focusing on developing molecules using broad mechanisms that have multiple links to oncogenic driver pathways in select patients, we have developed a diverse pipeline consisting of multiple distinct programs including kinases, targeted protein degraders, and precision antibody drug conjugates. Our pipeline is designed to serve patients with high unmet medical need, where there are limited or no treatment options. We believe we can best address these diseases by developing therapies that target primary and secondary resistance mechanisms.

We have several drug candidates in clinical development and our objective is to generate proof-of-concept clinical data to guide our future regulatory pathways to approval.

Our novel, first-in-class SMARCA2 degrader compounds represent our best opportunities for demonstrating clinical proof-of-concept in 2025 and advancing into potential Phase 2/3 registration studies.

PRT3789 is a first-in-class, highly selective degrader of SMARCA2 protein, which along with SMARCA4 controls gene regulation through chromatin remodeling. Cancer cells with SMARCA4 mutations are dependent on SMARCA2 for their growth and survival and selectively degrading SMARCA2 induces cell death in cancer cells while sparing normal cells in preclinical models. PRT3789 has been shown to be efficacious and well tolerated in multiple preclinical models of SMARCA4 deleted/mutated cancers as monotherapy and in combination with standards of care therapies. We believe a selective SMARCA2 degrader has the potential to be of benefit in up to 10% of non-small cell lung cancer, or NSCLC, patients in the United States including many other tumor types with the SMARCA4 mutation.

Patients with SMARCA4 mutated cancer have a poor clinical prognosis. We believe this represents an area of high unmet medical need. Therefore, mutated or deleted SMARCA4 cancers provide a potential biomarker to select those patients most likely to respond to treatment with a highly selective SMARCA2 degrader.

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PRT3789 is in Phase 1 clinical development in patients with biomarker selected SMARCA4-mutated cancers. We have completed enrollment of monotherapy dose escalation at the 665 mg once weekly IV dose and have selected 500 mg once weekly as the recommended Phase 2 dose. In addition, we have completed dose escalation in the combination of PRT3789 with docetaxel and we are nearing completion of backfill cohorts. Updated data from the trial is expected to be presented at a major medical meeting in the second half of 2025.

We are enrolling patients in a Phase 2 clinical trial evaluating PRT3789 in combination with KEYTRUDA (pembrolizumab) in patients with SMARCA4-mutated cancers, per the previously announced collaboration with Merck (known as MSD outside of the US and Canada).

Our discovery team has identified a series of potent, selective and orally bioavailable SMARCA2 degraders. In July 2024, we received IND clearance for the lead oral molecule, PRT7732. PRT7732 is >1000-fold selective for SMARCA2 vs. SMARCA4 and demonstrates robust activity in SMARCA4 deficient cancer models both as monotherapy and in combination with docetaxel at well-tolerated doses. PRT7732 demonstrates good oral bioavailability and half-life suitable for once daily oral dosing. In the fourth quarter of 2024, the we initiated and enrolled the first patients in a phase 1 multi-dose escalation trial of PRT7732 (NCT06560645) in biomarker selected SMARCA4 mutated cancers. Enrollment has advanced rapidly and we are currently enrolling patients in the fifth dose escalation cohort (60 mg once daily). We expect to provide an initial first-in-human data update at a major medical meeting in the second half of 2025.

As one of our first precision ADC programs we and our partner AbCellera began work on an early-stage discovery program involving potent degraders of the SMARCA family of proteins as payloads for novel antibodies targeting tumor specific antigens. Given the potent anti-tumor activity of these molecules in pre-clinical models of cancers beyond those targeted by our SMARCA2 selective degraders, we believe that these precision ADCs have the potential to extend the therapeutic utility of this class. The partnership includes up to five precision ADC targets. Under the terms of the agreement, we and AbCellera will jointly discover, develop, and commercialize products emerging from the collaboration. AbCellera will lead manufacturing activities and we will lead clinical development and global commercialization, subject to AbCellera's option to co-promote any resulting commercial products in the United States.

Outside of the AbCellera collaboration, we have discovered and optimized a number of pre-clinical precision payloads. We disclosed first data at the 36th EORTC-NCI-AACR Symposium describing preclinical proof-of-concept using a novel, potent SMARCA2/4 dual degrader as a "Precision Payload" conjugated to multiple antibodies. Prelude's SMARCA2/4 dual degraders have shown picomolar potency with potential for increased efficacy, selectivity and improved therapeutic index. Precision ADCs have potential to expand the reach of SMARCA degrader technology to cancers without SMARCA4 mutations.

We have discovered and are developing a series of selective and orally bioavailable KAT6A degraders. Optimized lead compounds are advancing to candidate nomination in the second quarter of 2025 with intent to file an IND in 2026. KAT6 is a clinically validated target with promising activity in breast cancer and other solid tumors. We recently presented preclinical data from this program at the American Association for Cancer Research (AACR) 2025 Annual Meeting. We intend to develop this program to IND and are open to development with a partner.

Our CDK9 candidate, PRT2527, is a potent and highly selective CDK9 inhibitor that has the potential to avoid off-target toxicities observed with other less selective CDK9 inhibitors. We presented interim phase 1 results of the dose-escalation study as part of a poster session at the 66th American Society of Hematology Annual Meeting (ASH) in the fourth quarter of 2024. PRT2527 demonstrated activity across a range of relapsed/refractory lymphoid malignancies, including patients who received prior CAR-T therapy. We also announced that we intend to seek a partner for any future continued advancement of PRT2527, as a result of our strategic focus on the SMARCA2 degrader development program.

Nasdaq Delisting Notice

On March 27, 2025, the Company received a letter (the "Bid Price Notice") from the Listing Qualifications staff (the "Staff") of The Nasdaq Stock Market LLC ("Nasdaq") indicating that, based upon the closing bid price of the Company's common stock for the prior 30 consecutive business days, the Company was not in compliance with the requirement to maintain a minimum bid price of $1.00 per share for continued listing on Nasdaq, as set forth in Nasdaq Listing Rule 5550(a)(2) (the "Minimum Bid Price Requirement").

The Bid Price Notice has no immediate effect on the continued listing status of the Company's common stock on Nasdaq, and, therefore, the Company's listing remains fully effective.

In accordance with Nasdaq Listing Rule 5810(c)(3)(A), the Company has been provided an initial compliance period of 180 calendar days, or until September 23, 2025, in which to regain compliance with the deficiency. In order to regain compliance with the Minimum Bid Price Requirement, the closing bid price of the common stock must be at least $1.00 per share for a minimum of ten consecutive business days during this 180-day period. If the Company does not regain compliance with this requirement by September 23, 2025, the Company may be eligible for an additional 180 calendar day compliance period provided that (i) the Company meets all

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other continued listing standards and (ii) the Company provides written notice to Nasdaq of its intention to cure the deficiency during the second grace period, generally by effecting a reverse stock split, if necessary.

If the Company does not regain compliance within the allotted compliance period(s), including any extensions that may be granted by Nasdaq, Nasdaq will provide notice that the Common Stock will be subject to delisting. At that time, the Company may appeal the Staff's determination to a Nasdaq Hearings Panel.

The Company intends to monitor the closing bid price of the common stock and consider its available options to resolve the noncompliance with the Minimum Bid Price Requirement.

There can be no assurance that the Company will be able to regain compliance with the Minimum Bid Price Requirement or will otherwise be in compliance with other Nasdaq listing criteria.

Components of Results of Operations

Since inception, we have devoted substantially all of our resources to developing product and technology rights, conducting research and development, organizing and staffing our company, business planning and raising capital. We have incurred recurring losses, the majority of which are attributable to research and development activities, and negative cash flows from operations. We have funded our operations primarily through the sale of convertible preferred stock, common stock and pre-funded warrants. Our net loss was $32.1 million and $31.4 million for the three months ended March 31, 2025 and 2024, respectively. As of March 31, 2025, we had an accumulated deficit of $615.6 million. Our primary use of cash is to fund operating expenses, which consist primarily of research and development expenditures, and to a lesser extent, general and administrative expenditures. Our ability to generate product revenue sufficient to achieve profitability will depend heavily on the successful development and eventual commercialization of one or more of our current or future product candidates. We expect to continue to incur significant expenses and operating losses for the foreseeable future as we advance our product candidates through all stages of development and clinical trials and, ultimately, seek regulatory approval. In addition, if we obtain marketing approval for any of our product candidates, we expect to incur significant commercialization expenses related to product manufacturing, marketing, sales and distribution. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending on the timing of our clinical trials and our expenditures on other research and development activities.

Revenue

To date, we have not recognized any revenue from product sales, and we do not expect to generate any revenue in the foreseeable future. If our development efforts for our product candidates are successful and result in regulatory approval, or license agreements with third parties, we may generate revenue in the future from product sales. However, there can be no assurance as to when we will generate such revenue, if at all.

Operating Expenses

Research and Development Expenses

Research and development expenses consist primarily of costs incurred in connection with the discovery and development of our product candidates. We expense research and development costs as incurred, including:

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We track outsourced development costs and other external research and development costs to specific product candidates on a program-by-program basis, fees paid to CROs, CMOs and research laboratories in connection with our preclinical development, process development, manufacturing and clinical development activities. However, we do not track our internal research and development expenses on a program-by-program basis as they primarily relate to compensation, early research and other costs which are deployed across multiple projects under development.

Research and development activities are central to our business model. Product candidates in later stages of clinical development generally have higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of later-stage clinical trials. We expect to continue to incur research and development expenses over the next several years related to personnel costs, including stock-based compensation, clinical trials, including later-stage clinical trials, for current and future product candidates and preparing regulatory filings for our product candidates.

General and Administrative Expenses

General and administrative expenses consist primarily of personnel expenses, including salaries, benefits and stock-based compensation expense, for employees and consultants in executive, finance and accounting, legal, operations support, information technology and human resource functions. General and administrative expense also includes corporate facility costs not otherwise included in research and development expense, including rent, utilities, depreciation and maintenance, as well as legal fees related to intellectual property and corporate matters and fees for accounting and consulting services.

We expect to continue to incur general and administrative expense in the future to support our continued research and development activities and potential commercialization efforts. These expenses will likely include costs related to the hiring of personnel and fees to outside consultants and legal support, among other expenses. The costs associated with being a public company include expenses related to services associated with maintaining compliance with the requirements of Nasdaq and the Securities and Exchange Commission, or SEC, insurance and investor relations costs. If any of our current or future product candidates obtains U.S. regulatory approval, we expect that we would incur significantly increased expenses associated with building a sales and marketing team.

Other Income, Net

Other income, net consists primarily of interest earned on our cash equivalents and marketable securities and grant income received from the State of Delaware. We anticipate re-applying for grants from the State of Delaware from time to time as long as we maintain qualifying headcount levels.

Income Taxes

Since our inception, we have not recorded any income tax benefits for the net operating losses, or NOLs, we have incurred or for our research and development tax credits, as we believe, based upon the weight of available evidence, that it is more likely than not that all of our NOLs and tax credits will not be realized.

Results of Operations

Comparison of the Three Months Ended March 31, 2025 and 2024

The following table sets forth our results of operations.

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Research and Development Expenses

Research and development expenses increased from $27.4 million for the three months ended March 31, 2024 to $28.8 million for the three months ended March 31, 2025. Included in research and development expenses for the three months ended March 31, 2025, was $2.3 million of non-cash expense related to stock-based compensation expense, including employee stock options, compared to $3.0 million for the three months ended March 31, 2024. Research and development expenses increased primarily due to an increase in expense related to our SMARCA2 clinical trials. Research and development expenses may fluctuate from period to period depending upon the stage of certain projects and the level of preclinical and clinical trial-related activities.

Research and development expenses by program are summarized in the table below. Expenses for programs that have been discontinued are included in Other.

General and Administrative Expenses

General and administrative expenses decreased from $6.9 million for the three months ended March 31, 2024 to $5.8 million for the three months ended March 31, 2025. The decrease was primarily driven by a decrease in non-cash expense related to stock-based compensation expense. Included in general and administrative expenses for the three months ended March 31, 2025, was $1.6 million of non-cash expense related to stock-based compensation expense compared to $2.5 million for the three months ended March 31, 2024, due to the tapering off of the vesting period of prior granted options and lower valuation on more recent grants due to the decrease in our stock price.

Other Income, net

Other income, net decreased from $2.9 million for the three months ended March 31, 2024, to $2.5 million for the three months ended March 31, 2025 primarily due to lower income earned our investments due to lower balances offset by the receipt and recognition of research and development tax credits.

Liquidity and Capital Resources

Overview

Since our inception, we have not recognized any product revenue and have incurred operating losses and negative cash flows from our operations. We have not yet commercialized any product and we do not expect to generate revenue from sales of any products for several years, if at all.

At March 31, 2025 the Company had cash, cash equivalents, restricted cash and marketable securities totaling $103.1 million. Absent additional funding, the Company believes that its cash, cash equivalents, restricted cash and marketable securities will not be sufficient fund its operating expenses and capital expenditure requirements for at least the next twelve months from the filing date of this Quarterly Report on Form 10-Q. As a result, substantial doubt exists about our ability to continue as a going concern.

Since our inception, we have funded our operations primarily through the sale of convertible preferred stock, common stock, and pre-funded warrants. We will need to raise substantial additional capital to support our continuing operations and pursue our growth strategy. Until such time as we can generate significant revenue from product sales, if ever, we plan to finance our operations through the sale of equity, debt financings or other capital sources, which may include collaborations with other companies or other strategic transactions. There are no assurances that we will be successful in obtaining an adequate level of financing as and when needed to finance our operations on terms acceptable to us or at all. Any failure to raise capital as and when needed could have a negative impact

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on our financial condition and on our ability to pursue our business plans and strategies. If we are unable to secure adequate additional funding, we may have to significantly delay, scale back or discontinue the development and commercialization of one or more product candidates or delay our pursuit of potential in-licenses or acquisitions.

Funding Requirements

Our primary use of cash is to fund operating expenses, primarily research and development expenditures. Cash used to fund operating expenses is impacted by the timing of when we pay these expenses, as reflected in the change in our outstanding accounts payable, accrued expenses and prepaid expenses.

Because of the numerous risks and uncertainties associated with research, development and commercialization of pharmaceutical products, we are unable to estimate the exact amount of our operating capital requirements. Our future funding requirements will depend on many factors, including, but not limited to:

We will need additional funds to meet operational needs and capital requirements for clinical trials, other research and development expenditures, and business development activities. We currently have no credit facility or committed sources of capital. Because of the numerous risks and uncertainties associated with the development and commercialization of our product candidates, we are unable to estimate the amounts of increased capital outlays and operating expenditures associated with our current and anticipated clinical studies.

In May 2024, the Company filed a shelf registration statement (the "2024 Shelf Registration Statement") with the SEC for the issuance of common stock, preferred stock, debt securities, warrants, subscription rights and units up to an aggregate amount of $400 million. The 2024 Shelf Registration statement was declared effective on June 10, 2024. The 2024 Shelf Registration statement expires in May 2027, and as of March 31, 2025 there was $400 million remaining under the 2024 Shelf Registration Statement.

In March 2023, in connection with filing a prospectus supplement to our shelf registration statement previously filed in November 2021 (the "2021 Shelf Registration Statement"), we entered into an Open Market Sales Agreement (the "Sales Agreement") with Jefferies LLC, as the sales agent, pursuant to which we may offer and sell shares of our common stock having an aggregate offering amount of up to $75.0 million. We will pay Jefferies LLC a commission rate of up to 3.0% of the aggregate gross proceeds from the sale of any shares of common stock pursuant to the Sales Agreement. In November 2024, the 2021 Shelf Registration Statement expired with respect to the shares to be sold under the Sales Agreement. Accordingly, we expect to file a prospectus supplement to the 2024 Shelf Registration Statement in order to continue to allow us to access the Sales Agreement. We have $75.0 million remaining under the Sales Agreement as of March 31, 2025.

Until such time, if ever, as we can generate substantial product revenue, we expect to finance our operations through a combination of equity offerings, debt financings, collaborations, strategic alliances and marketing, distribution or licensing arrangements. To the extent that we raise additional capital through the sale of equity or convertible debt securities, ownership interests will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants

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limiting or restricting our ability to take specific actions, such as incurring additional debt, making acquisitions or capital expenditures or declaring dividends. If we raise additional funds through collaborations, strategic alliances or marketing, distribution or licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates, or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings or other arrangements when needed, we may be required to delay, limit, reduce or terminate our research, product development or future commercialization efforts, or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

Cash Flows

The following table shows a summary of our cash flows for the periods indicated:

Operating Activities

During the three months ended March 31, 2025, we used $34.2 million of cash in operating activities. Cash used in operating activities reflected our net loss of $32.1 million and a $6.9 million net increase in our operating assets and liabilities offset by noncash charges of $4.7 million, which primarily consisted of stock-based compensation. The primary use of cash was to fund our operations related to the development of our product candidates.

During the three months ended March 31, 2024, we used $31.8 million of cash in operating activities. Cash used in operating activities reflected our net loss of $31.4 million and a $5.2 million net increase in our operating assets and liabilities, offset by noncash charges of $4.8 million, which primarily consisted of stock-based compensation. The primary use of cash was to fund our operations related to the development of our product candidates.

Investing Activities

During the three months ended March 31, 2025, net cash provided by investing activities of $62.2 million consisted primarily of $71.7 million in proceeds from maturities of marketable securities, partially offset by $9.5 million in purchases of marketable securities. During the three months ended March 31, 2024, net cash used in investing activities of $31.2 million consisted primarily of $37.0 million in proceeds from maturities of marketable securities, partially offset by $5.5 million in purchases of marketable securities.

Financing Activities

For the three months ended March 31, 2025 net cash used in financing activities was primarily for principal payments on our finance lease.

Critical Accounting Estimates

During the three months ended March 31, 2025, there were no other material changes to our critical accounting policies and estimates from those described under the heading "Management's Discussion and Analysis of Financial Condition and Results of Operations-Critical Accounting Estimates" in our 2024 Annual Report on Form 10-K.

Emerging Growth Company and Smaller Reporting Company Status

In April 2012, the JOBS Act was enacted. Section 107 of the JOBS Act provides that an "emerging growth company" can take advantage of the extended transition period provided in Section 7(a)(2)(B) of the Securities Act of 1933, as amended, for complying with new or revised accounting standards. Thus, an emerging growth company can delay the adoption of certain accounting standards

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until those standards would otherwise apply to private companies. We have elected to avail ourselves of this exemption from complying with new or revised accounting standards and, therefore, will not be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies. As a result, our financial statements may not be comparable to companies that comply with new or revised accounting pronouncements as of public company effective dates.

Subject to certain conditions, as an emerging growth company, we may rely on certain other exemptions and reduced reporting requirements, including without limitation, exemption to the requirements for providing an auditor's attestation report on our system of internal controls over financial reporting pursuant to Section 404(b) of the Sarbanes-Oxley Act. We will remain an emerging growth company until the earlier to occur of (a) the last day of the fiscal year (i) following the fifth anniversary of the completion of our initial public offering (i.e. December 31, 2025), (ii) in which we have total annual gross revenues of at least $1.235 billion or (iii) in which we are deemed to be a "large accelerated filer" under the rules of the SEC, which means the market value of our common stock that is held by non-affiliates exceeds $700.0 million as of the prior June 30th, or (b) the date on which we have issued more than $1.0 billion in non-convertible debt during the prior three-year period.

We are also a "smaller reporting company," meaning that the market value of our stock held by non-affiliates is less than $700.0 million and our annual revenue is less than $100.0 million during the most recently completed fiscal year. We may continue to be a smaller reporting company after if either (i) the market value of our stock held by non-affiliates is less than $250.0 million or (ii) our annual revenue is less than $100.0 million during the most recently completed fiscal year and the market value of our stock held by non-affiliates is less than $700.0 million. If we remain a smaller reporting company once we cease to be an emerging growth company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company we may choose to present only the two most recent fiscal years of audited financial statements in our Annual Report on Form 10-K and, similar to emerging growth companies, smaller reporting companies have reduced disclosure obligations regarding executive compensation.

Item 3. Quantitative and Qualitative Disclosures About Market Risk.

We are a smaller reporting company as defined by Rule 12b-2 of the Exchange Act and are not required to provide the information required under this item with respect to the period ending March 31, 2025.

Item 4. Controls and Procedures.

Evaluation of Disclosure Controls and Procedure

As of March 31, 2025, management, with the participation of our Principal Executive Officer and Principal Financial and Accounting Officer, performed an evaluation of the effectiveness of the design and operation of our disclosure controls and procedures as defined in Rules 13a-15(e) and 15d-15(e) of the Securities Exchange Act of 1934, as amended, or the Exchange Act. Our disclosure controls and procedures are designed to ensure that information required to be disclosed in the reports we file or submit under the Exchange Act is recorded, processed, summarized, and reported within the time periods specified in the SEC's rules and forms, and that such information is accumulated and communicated to our management, including the Principal Executive Officer and the Principal Financial and Accounting Officer, to allow timely decisions regarding required disclosures. Any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objective and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Based on this evaluation, our Principal Executive Officer and Principal Financial and Accounting Officer concluded that, as of March 31, 2025, the design and operation of our disclosure controls and procedures were effective at a reasonable assurance level.

Changes in Internal Control over Financial Reporting

Management determined that, as of March 31, 2025, there were no changes in our internal control over financial reporting that occurred during the fiscal quarter then ended that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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PART II- OTHER INFORMATION

Item 1. LegalProceedings.

From time to time, we may be involved in legal proceedings arising in the ordinary course of our business. In addition, we may receive letters alleging infringement of patents or other intellectual property rights. We are not presently a party to any legal proceedings that, in the opinion of management, would have a material adverse effect on our business, operating results, cash flows or financial conditions should such litigation be resolved unfavorably. Regardless of outcome, litigation can have an adverse impact on us due to defense and settlement costs, diversion of management resources, negative publicity and reputational harm, and other factors.

Item 1A. Risk Factors

Investing in our common stock involves a high degree of risk. Before making your decision to invest in shares of our common stock, you should carefully consider the risks and uncertainties described under Part I, Item 1A, "Risk Factors" in our 2024 Annual Report on Form 10-K filed with the Securities and Exchange Commission on March 10, 2025 in addition to the risk factor below.

If we are unable to comply with the continued listing requirements of the Nasdaq Capital Market, our common stock could be delisted, which could affect our common stock's market price and liquidity and reduce our ability to raise capital.

Our common stock is listed on Nasdaq, which imposes continued listing requirements with respect to issuers whose securities are listed on Nasdaq. If we fail to satisfy the continued listing standards, such as, for example, Nasdaq's Minimum Bid Price Requirement, Nasdaq may issue a non-compliance letter or initiate delisting proceedings.

As previously disclosed, on March 27, 2025, we received such a letter from the Staff notifying us that based upon the closing bid price of the Company's common stock, for the prior 30 consecutive business days, the Company was not in compliance with the requirement to maintain a minimum bid price of $1.00 per share for continued listing on Nasdaq, as set forth in Nasdaq Listing Rule 5550(a)(2).

In accordance with Nasdaq Listing Rule 5810(c)(3)(A), the Company has been provided an initial compliance period of 180 calendar days, or until September 23, 2025, in which to regain compliance with the deficiency. In order to regain compliance with the Minimum Bid Price Requirement, the closing bid price of the Common Stock must be at least $1.00 per share for a minimum of ten consecutive business days during this 180-day period. If the Company does not regain compliance with this requirement by September 23, 2025, the Company may be eligible for an additional 180 calendar day compliance period provided that (i) the Company meets all other continued listing standards and (ii) the Company provides written notice to Nasdaq of its intention to cure the deficiency during the second grace period, by effecting a reverse stock split, if necessary.

If the Company does not regain compliance within the allotted compliance period(s), including any extensions that may be granted by Nasdaq, Nasdaq will provide notice that the common stock will be subject to delisting. At that time, the Company may appeal the Staff's determination to a Nasdaq Hearings Panel.

If we are unable to maintain compliance with the continued listing requirements of Nasdaq, our common stock could be delisted, making it more difficult to buy or sell our securities and to obtain accurate quotations, and the price of our securities could suffer a material decline. Delisting could also impair our ability to raise capital.

Our financial statements contain a statement regarding a substantial doubt about the Company's ability to continue as a going concern.

We had no revenue during the three months ended March 31, 2025. Our primary uses of cash are to fund our planned clinical trials, research and development expenditures and for operating expenses. Cash used to fund operating expenses is based on the assumption that we will continue as a going concern, which contemplates the realization of assets and liquidation of liabilities in the normal course of business. We face certain risks and uncertainties that are present in many emerging pharmaceutical companies regarding product development, limited working capital, recurring losses and negative cash flow from operations, future profitability, ability to obtain future capital, protection of patents, technologies and property rights, competition, navigating the domestic and major foreign markets' regulatory and clinical environment, recruiting and retaining key personnel, dependence on third party manufacturing organizations, third party collaboration and licensing agreements, lack of sales and marketing activities. We currently have no customers or pharmaceutical products to sell or distribute. Absent additional funding, we believe that our cash, cash equivalents, and marketable securities will not be sufficient to fund our operating expenses and capital expenditure requirements for at least the next twelve months from the filing date of this Quarterly Report on Form 10-Q. These risks and other factors raise substantial doubt about our ability to continue as a going concern.

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Our ability to continue as a going concern is dependent on our ability to obtain the necessary financing to meet our obligations and repay our liabilities arising from the ordinary course of business operations when they become due. The substantial doubt about our ability to continue as a going concern may affect the price of our common stock, may impact our relationship with third parties with whom we do business and may impact our ability to raise additional capital.

Item 2. Unregistered Sales of Equity Securities and Use of Proceeds.

None.

Item 3. Defaults UponSenior Securities.

None.

Item 4. Mine Safety Disclosures.

Not applicable.

Item 5. OtherInformation.

None.

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Item 6. Exhibits.

Furnish the exhibits required by Item 601 of Regulation S-K (§ 229.601 of this chapter).

*The certifications furnished in Exhibits 32.1 and 32.2 hereto are deemed to accompany this Form 10-Q and are not deemed "filed" for purposes of Section 18 of the Exchange Act, or otherwise subject to the liability of that section, nor shall they be deemed incorporated by reference into any filing under the Securities Act or the Exchange Act.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

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