Financial Analysis

7. Term Loan In May 2024, we, as borrower, entered into the K2HV Loan Agreement with K2HV (together with any other lender from time to time, the Lenders); K2HV, as administrative agent for the Lenders (in such capacity, together with its successors, the Administrative Agent); and Ankura Trust Company, LLC, as collateral trustee for the Lenders (the Collateral Trustee). The K2HV Loan Agreement provided up to $60.0 million principal in term loans. We received $30.0 million in gross loan proceeds at closing; $25.0 million from the first tranche commitment and $5.0 million from the second tranche commitment. A third tranche commitment of up to $10.0 million was available to be drawn at our option through June 30, 2025, subject to the achievement, as determined by the Administrative Agent in its discretion, of certain time-based, clinical and regulatory milestones and receipt of not less than $60.0 million in net cash proceeds from certain financing activities, with at least $50.0 million from a single offering of common stock. Our ability to draw upon the third tranche commitment expired on June 30, 2025 without being drawn upon. A fourth tranche commitment of up to $20.0 million was available to be drawn at our option through May 1, 2026, subject to Lenders review of our clinical, financial and operating plan and subject to the Lenders consent in its sole and absolute discretion. Our ability to draw upon the fourth tranche commitment expired on May 1, 2026 without being drawn up …

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9. Stock-based Compensation 2017 Stock Incentive Plan In December 2017, we adopted the 2017 Stock Incentive Plan (the 2017 Plan), as amended and restated, pursuant to which we have outstanding stock options. No future awards may be granted under the 2017 Plan. 2021 Stock Incentive Plan In April 2021, our board of directors adopted and our stockholders approved the 2021 Stock Incentive Plan (the 2021 Plan), which became effective immediately prior to the effectiveness of our initial public offering (the IPO). As a result of the adoption of the 2021 Plan, no further awards will be made under the 2017 Plan. The 2021 Plan provides for the grant of incentive stock options (ISOs), non-qualified stock options, restricted stock awards (RSAs), restricted stock units (RSUs), stock appreciation rights and other stock-based awards. Our employees, officers, directors, consultants and advisors are eligible to receive awards under the 2021 Plan. The terms of awards, including vesting requirements, are determined by our board of directors, subject to the provisions of the 2021 Plan. We initially registered 3,352,725 shares of common stock under the 2021 Plan, pursuant to a Registration Statement on Form S-8 filed with the SEC on April 30, 2021, which was comprised of (i) 2,843,116 shares of common stock reserved for issuance under the 2021 Plan, (ii) 31,884 shares of common stock originally reserved for issuance under the 2017 Plan that became available for issuance under the 2021 Plan upon …

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5. Financial Instruments and Fair Value Measurements Our assets that are required to be measured at fair value on a recurring basis consist of money market funds classified as cash and cash equivalents on our condensed consolidated balance sheets as of June 30, 2026 and December 31, 2025. Our liabilities that are required to be measured at fair value on a recurring basis consist of a derivative liability pursuant to a loan and security agreement (the K2HV Loan Agreement) with K2 HealthVentures LLC (K2HV) (see Note 7, Term Loan ) on our condensed consolidated balance sheet as of December 31, 2025. We do not have any liabilities that are required to be measured at fair value on a recurring basis as of June 30, 2026. The carrying amounts reflected in the condensed consolidated balance sheets for cash, prepaid expenses and other current assets, accounts payable and accrued expenses approximate their fair values, due to their short-term nature. Assets measured at fair value on a recurring basis as of June 30, 2026 were as follows: Level 1 Level 2 Level 3 Total (in thousands) Assets: Money market funds $ 21,489 $ $ $ 21,489 Total assets $ 21,489 $ $ $ 21,489 Assets and liabilities measured at fair value on a recurring basis as of December 31, 2025 were as follows: Level 1 Level 2 Level 3 Total (in thousands) Assets: Money market funds $ 56,548 $ $ $ 56,548 Total assets $ 56,548 $ $ $ 56,548 Liabilities: Derivative liability $ $ $ 759 $ 759 Total liabilities $ $ $ 759 $ 759 There we …

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13. Lease Termination On May 7, 2026 (the Modification Date), we entered into an Agreement for Termination of Lease and Voluntary Surrender of Premises (the Lease Termination) with ARE-770/784/790 Memorial Drive, LLC (the Landlord), pursuant to which we and the Landlord agreed to terminate that certain lease, dated June 1, 2021, as amended, by and between us and the Landlord (the Lease), effective October 31, 2026 (the Lease Termination Date). Either party may elect to accelerate the Lease Termination Date by providing 30 days prior written notice to the other party, provided that such notice is given no earlier than July 1, 2026 (the Termination Option). Under the Lease, we leased approximately 25,778 square feet of space, consisting of the entire building located at 200 Talcott Avenue, Watertown, Massachusetts. Pursuant to the Lease Termination, we paid the Landlord an aggregate termination fee of $2.7 million, which represented full satisfaction of all remaining payments and other financial obligations due from us to the Landlord under the Lease including, without limitation, Base Rent (as defined in the Lease) for the months of May 2026 through October 2026. We have no further rent obligations to the Landlord pursuant to the Lease after the Lease Termination Date. We have assessed the Lease Termination and have concluded that it represents a modification to the Lease within the scope of ASC Topic 842, Leases (ASC 842). Upon the execution of the Lease Termination, we were …

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Recent Accounting Pronouncements In November 2024, the FASB issued ASU No. 2024-03, Income StatementReporting Comprehensive IncomeExpense Disaggregation Disclosures (Subtopic 220-04) (ASU No. 2024-03), which requires the disclosure of additional information about specific expense categories in the notes to the consolidated financial statements at interim and annual reporting periods. The provisions of ASU No. 2024-03 are effective for annual reporting periods beginning after December 31, 2026, with early adoption permitted. We are currently evaluating the impact that this standard will have on our consolidated financial statements. Other accounting standards that have been issued or proposed by the FASB or other standards-setting bodies that do not require adoption until a future date are not expected to have a material impact on our consolidated financial statements upon adoption. …

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2. Strategic Review and Liquidity In February 2026, we adopted a restructuring plan to extend our capital resources (the 2026 Restructuring) in connection with initiating a process to explore a full range of strategic alternatives to advance our promising platform and drug development pipeline to maximize stockholder value. We have engaged Piper Sandler & Co. (Piper Sandler) to serve as exclusive financial advisor to assist in the strategic review process. Measures contemplated during the strategic review process include the asset purchase agreement described in Note 4, and may also include, among other options, a sale of the Company, a business combination or merger, a sale of our assets, licensing or collaboration arrangements, or other strategic transactions. There can be no assurance that the strategic review process will result in any agreement or transaction that will enhance stockholder value, or any agreement or transaction at all. As part of the 2026 Restructuring, our board of directors approved a reduction in force in February 2026, representing 64% of our workforce to better align our resources with our pursuit of strategic alternatives. In May 2026, an additional reduction in force occurred, representing 36% of our workforce at that time. See Note 12 for further discussion of the impact of the 2026 Restructuring. We had cash and cash equivalents of $22.0 million at June 30, 2026. The outcome of our strategic review process will inform future development plans …

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11. Segment Information We have one reportable segment which focuses on the discovery and development of cancer therapeutics. The segment derives its revenue from the Purchase Agreement with Jazz (see Note 4, Collaboration Revenue ). Our chief operating decision maker (CODM) manages our operations on an integrated basis for the purpose of allocating resources. When evaluating our financial performance, our CODM regularly reviews total expenses and expenses by function and makes decisions using this information based on the performance of the enterprise as a whole. Our CODM primarily evaluates the performance of the enterprise based on results that have a direct impact on our available cash and cash equivalents and accordingly places less significance on non-cash expenses such as stock-based compensation and depreciation expenses in determining how to allocate resources. Segment assets regularly reviewed by our CODM include measures of liquidity, primarily available cash and cash equivalents, and are consistent with the presentation of cash and cash equivalents reported in our condensed consolidated balance sheets. The following is a summary of our segment and consolidated net income (loss), including significant segment expenses: Three Months Ended June 30, Six Months Ended June 30, 2026 2025 2026 2025 (in thousands) Collaboration revenue $ 21,000 $ $ 21,000 $ Less: General and administrative support 6,678 3,486 11,250 7,309 Clinical development 3,047 5,710 6,690 10,039 Resea …

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8. Common and Preferred Stock Common Stock We are authorized to issue 200,000,000 shares of common stock. Common stockholders are entitled to dividends if and when declared by our board of directors. As of June 30, 2026, no dividends on common stock had been declared by us. On May 10, 2022, we entered into a Sales Agreement (the Sales Agreement) with Leerink Partners LLC (Leerink Partners), pursuant to which we are entitled to offer and sell shares of our common stock (the ATM Offering). The Sales Agreement provides that Leerink Partners will be entitled to a sales commission equal to 3.0% of the gross sales price per share of all shares sold under the ATM Offering. We were initially entitled to offer and sell shares of our common stock having an aggregate offering price of up to $50.0 million in the ATM Offering, which was subsequently increased in February 2024 to $75.0 million. On May 8, 2025, we filed a new Registration Statement on Form S-3 and filed a new prospectus covering the ATM Offering (the Prospectus) for the offer and sale of shares of our common stock with an aggregate offering price of up to $12.5 million in the ATM Offering as a result of being subject to General Instruction I.B.6 of Form S-3 (the Baby Shelf Limitation). As of June 30, 2026, we remain subject to the Baby Shelf Limitation. During the six months ended June 30, 2026, we did not sell any shares of our common stock under the ATM Offering. During the six months ended June 30, 2025, we sold 421,766 …

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