Werewolf Therapeutics, Inc. 10-Q

Item 1. Financial Statements Werewolf Therapeutics, Inc. Condensed Consolidated Balance Sheets (unaudited) (amounts in thousands, except share and per share amounts) June 30, 2024 December 31, 2023 Assets Current assets: Cash and cash equivalents $ 135,303 $ 134,343 Prepaid expenses and other current assets 2,940 2,677 Other receivables 545 1,350 Total current assets 138,788 138,370 Property and equipment, net 7,092 7,958 Restricted cash and cash equivalents, net of current portion 1,211 21,023 Operating lease right of use asset 6,347 6,888 Other assets 265 594 Total assets $ 153,703 $ 174,833 Liabilities and stockholders’ equity Current liabilities: Accounts payable $ 1,467 $ 1,336 Accrued expenses and other current liabilities 8,701 8,860 Operating lease liability, current 1,274 1,608 Deferred revenue, current — 907 Note payable, current — 6,667 Total current liabilities 11,442 19,378 Operating lease liability, net of current portion 10,239 10,992 Deferred revenue, net of current portion — 433 Note payable, net of discount, issuance costs, and current portion 25,163 32,656 Derivative liability 2,841 — Total liabilities 49,685 63,459 Commitments and contingencies Stockholders’ equity: Preferred stock, $ 0.0001 par value, 5,000,000 shares authorized as of June 30, 2024 and December 31, 2023; no shares issued or outstanding as of June 30, 2024 and December 31, 2023 — — Common stock, $ 0.0001 par value, 200,000,000 shares authorized as of June 30, 2024 and December 31, 2023; 43,702,147 and 39,107,048 shares issued and outstanding as of June 30, 2024 and December 31, 2023, respectively 4 4 Additional paid-in capital 481,529 455,443 Accumulated deficit ( 377,515 ) ( 344,073 ) Total stockholders’ equity 104,018 111,374 Total liabilities and stockholders’ equity $ 153,703 $ 174,833 The accompanying notes are an integral part of these condensed consolidated financial statements. 4 Table of Contents Werewolf Therapeutics, Inc. Condensed Consolidated Statements of Operations (unaudited) (amounts in thousands, except share and per share amounts) Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 Revenue: Collaboration revenue $ 1,143 $ 8,081 $ 1,885 $ 12,545 Operating expenses: Research and development 15,271 9,583 28,179 21,289 General and administrative 4,832 4,565 9,828 9,546 Total operating expenses 20,103 14,148 38,007 30,835 Operating loss ( 18,960 ) ( 6,067 ) ( 36,122 ) ( 18,290 ) Other income: Interest income 1,793 1,949 3,766 3,467 Interest expense ( 1,142 ) ( 955 ) ( 2,145 ) ( 1,126 ) Loss on extinguishment of debt ( 553 ) — ( 553 ) — Other income (expense), net 1,613 ( 25 ) 1,612 ( 1,131 ) Total other income 1,711 969 2,680 1,210 Net loss $ ( 17,249 ) $ ( 5,098 ) $ ( 33,442 ) $ ( 17,080 ) Net loss per common share, basic $ ( 0.40 ) $ ( 0.14 ) $ ( 0.79 ) $ ( 0.49 ) Net loss per common share, diluted $ ( 0.43 ) $ ( 0.14 ) $ ( 0.82 ) $ ( 0.49 ) Weighted-average common shares outstanding, basic 43,521,406 35,557,701 42,564,342 35,173,327 Weighted-average common shares outstanding, diluted 44,043,184 35,557,701 42,825,231 35,173,327 The accompanying notes are an integral part of these condensed consolidated financial statements. 5 Table of Contents Werewolf Therapeutics, Inc. Condensed Consolidated Statements of Stockholders’ Equity (unaudited) (amounts in thousands, except share amounts) Common Stock Additional Paid-in Capital Accumulated Deficit Total Stockholders’ Equity Shares Amount Balance at December 31, 2023 39,107,048 $ 4 $ 455,443 $ ( 344,073 ) $ 111,374 Issuance of common stock from at the market offering, net of issuance costs of $ 985 4,169,324 — 20,089 — 20,089 Stock-based compensation expense — — 2,305 — 2,305 Stock option exercises 5,999 — 12 — 12 Net loss — — — ( 16,193 ) ( 16,193 ) Balance at March 31, 2024 43,282,371 4 477,849 ( 360,266 ) 117,587 Issuance of common stock from at the market offering, net of issuance costs of $ 61 172,996 — 1,002 — 1,002 Issuance of common stock, net 246,680 — 76 — 76 Stock-based compensation expense — — 2,602 — 2,602 Stock option exercises 100 — — — — Net loss — — — ( 17,249 ) ( 17,249 ) Balance at June 30, 2024 43,702,147 $ 4 $ 481,529 $ ( 377,515 ) $ 104,018 Common Stock Additional Paid-in Capital Accumulated Deficit Total Stockholders’ Equity Shares Amount Balance at December 31, 2022 31,515,074 $ 3 $ 429,039 $ ( 306,705 ) $ 122,337 Issuance of common stock from at the market offering, net of issuance cost of $ 103 3,824,249 — 8,610 — 8,610 Stock-based compensation expense — — 2,108 — 2,108 Net loss — — — ( 11,982 ) ( 11,982 ) Balance at March 31, 2023 35,339,323 3 439,757 ( 318,687 ) 121,073 Issuance of common stock from at the market offering, net of issuance costs of $ 31 272,032 — 644 — 644 Issuance of common stock, net 28,739 — 45 45 Stock-based compensation expense — — 1,930 — 1,930 Stock option exercises 1,690 — 5 — 5 Net loss — — — ( 5,098 ) ( 5,098 ) Balance at June 30, 2023 35,641,784 $ 3 $ 442,381 $ ( 323,785 ) $ 118,599 The accompanying notes are an integral part of these condensed consolidated financial statements. 6 Table of Contents Werewolf Therapeutics, Inc. Condensed Consolidated Statements of Cash Flows (unaudited) (amounts in thousands) Six Months Ended June 30, 2024 2023 Operating activities: Net loss $ ( 33,442 ) $ ( 17,080 ) Adjustments to reconcile net loss to net cash used in operating activities: Stock-based compensation expense 4,907 4,038 Depreciation expense 918 859 Non-cash interest expense 410 92 Non-cash lease expense 541 675 Loss on extinguishment of debt 553 — Change in fair value of derivative liabilities ( 1,609 ) — Change in fair value of success payment liability — ( 1,030 ) Amortization of debt issuance costs — 60 Changes in operating assets and liabilities: Prepaid expenses and other assets ( 474 ) 863 Other receivables 805 1 Other non-current assets 329 — Accounts payable, accrued expenses and other liabilities 15 ( 3,017 ) Deferred revenue ( 1,340 ) ( 5,271 ) Operating lease liability ( 1,087 ) ( 1,009 ) Net cash used in operating activities ( 29,474 ) ( 20,819 ) Investing activities: Purchases of property and equipment ( 128 ) ( 350 ) Net cash used in investing activities ( 128 ) ( 350 ) Financing activities: Proceeds from at the market offering of common stock, net of issuance costs 21,124 9,265 Proceeds from drawdown of term loans 30,000 40,000 Payment of debt issuance costs ( 673 ) — Repayment of term loan ( 40,000 ) — Proceeds from issuances under Employee Stock Purchase Plan 76 45 Proceeds from stock option exercises 12 5 Net cash provided by financing activities 10,539 49,315 Net (decrease) increase in cash, cash equivalents and restricted cash and cash equivalents ( 19,063 ) 28,146 Cash, cash equivalents and restricted cash and cash equivalents—beginning of period 155,577 130,529 Cash, cash equivalents and restricted cash and cash equivalents—end of period $ 136,514 $ 158,675 Reconciliation of cash, cash equivalents and restricted cash and cash equivalents to the condensed consolidated balance sheets Cash and cash equivalents $ 135,303 $ 137,452 Prepaid expenses and other current assets — 208 Restricted cash and cash equivalents, net of current portion 1,211 21,015 Total cash, cash equivalents and restricted cash and cash equivalents $ 136,514 $ 158,675 Supplemental disclosure of cash flow information: Cash paid for interest $ 1,788 $ 742 Supplemental disclosure of non-cash investing and financing activities: Purchases of property and equipment in accounts payable and accrued expenses $ — $ 13 Issuance costs in accounts payable and accrued expenses $ 69 $ 15 Fair value of derivative liability issued with term loan $ 4,450 $ — The accompanying notes are an integral part of these condensed consolidated financial statements. 7 Table of Contents Werewolf Therapeutics, Inc. Notes to Condensed Consolidated Financial Statements (unaudited) 1. Nature of Business Werewolf Therapeutics, Inc. was incorporated in the state of Delaware in October 2017. As used throughout these unaudited, condensed consolidated financial statements, the terms “Werewolf,” “we,” “us,” and “our” refer to the business of Werewolf Therapeutics, Inc., and its wholly owned subsidiary. We are an innovative biopharmaceutical company pioneering the development of therapeutics engineered to stimulate the body’s immune system for the treatment of cancer. Our headquarters are located in Watertown, Massachusetts. Since inception, we have devoted substantially all of our efforts and financial resources to organizing and staffing the company; business planning; raising capital; developing and optimizing our platform technology; identifying potential product candidates; enhancing our intellectual property portfolio; undertaking research, preclinical studies, and clinical trials; and enabling manufacturing for our development programs. We are subject to risks and uncertainties common to early-stage companies in the biotechnology industry including, but not limited to, technical risks associated with the successful research, development and manufacturing of product candidates, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. Current and future programs will require significant research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure. Even if our product development efforts are successful, it is uncertain when, if ever, we will realize significant revenue from product sales. We had cash and cash equivalents of $ 135.3 million at June 30, 2024. We expect that our cash and cash equivalents will enable us to fund our operating expenses and capital expenditure requirements for at least twelve months from the date of issuance of the condensed consolidated financial statements in this Form 10-Q. However, additional funding will be necessary beyond this point to fund future preclinical and clinical activities. We expect to finance our future cash needs through a combination of equity or debt financings, collaboration agreements, strategic alliances and licensing arrangements. 2. Summary of Significant Accounting Policies Basis of Presentation and Consolidation The accompanying condensed consolidated financial statements as of June 30, 2024 and December 31, 2023, and for the three and six months ended June 30, 2024 and 2023, have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the “SEC”) and generally accepted accounting principles in the United States of America (“GAAP”) as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”) for condensed consolidated financial information. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, these condensed consolidated financial statements reflect all normal recurring adjustments which are necessary for a fair presentation of our financial position and results of our operations, as of and for the periods presented. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto contained in our Annual Report on Form 10-K for the year ended December 31, 2023 filed with the SEC on March 7, 2024 (the “2023 Annual Report”). The information presented in the condensed consolidated financial statements and related notes as of June 30, 2024, and for the three and six months ended June 30, 2024 and 2023, is unaudited. The December 31, 2023 condensed consolidated balance sheet included herein was derived from the audited financial statements as of that date, but does not include all disclosures, including notes, required by GAAP for complete financial statements. Interim results for the three and six months ended June 30, 2024 are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2024, or any future period. The accompanying condensed consolidated financial statements include the accounts of Werewolf Therapeutics, Inc. and its wholly owned subsidiary, Werewolf Therapeutics Mass Securities, Inc. All intercompany transactions and balances have been eliminated in consolidation. Summary of Significant Accounting Policies The significant accounting policies and estimates used in the preparation of the condensed consolidated financial statements are described in our audited financial statements as of and for the year ended December 31, 2023, and the notes thereto, which are included in the 2023 Annual Report. Other than as set forth below there have been no material changes in our significant accounting policies during the six months ended June 30, 2024. 8 Table of Contents Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, those related to revenue recognition, accrued expenses, assumptions used in the valuation of stock-based compensation expense and the fair value of the derivative liability, and income taxes. Actual results could differ from those estimates. Recently Adopted Accounting Pronouncements In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU No. 2020-06”), which reduces the number of accounting models for convertible debt instruments and convertible preferred stock as well as amends the derivatives scope exception for contracts in an entity’s own equity. ASU No. 2020-06 also simplifies the diluted earnings per share calculation in certain areas. We adopted ASU No. 2020-06 on January 1, 2024. The adoption did not have a material impact on the condensed consolidated financial statements. Recent Accounting Pronouncements In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU No. 2023-09”), which enhances the transparency and decision usefulness of income tax disclosures primarily related to rate reconciliation and income taxes paid. The provisions of ASU No. 2023-09 are effective for fiscal years beginning after December 15, 2024, with early adoption permitted, and are required to be applied on a prospective basis. Our management is 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. Subsequent Events We have evaluated subsequent events and transactions that occurred after the balance sheet date up to the date that the financial statements were issued. Other than as described in these condensed consolidated financial statements, we did not identify any subsequent events that require adjustment or disclosure in the condensed consolidated financial statements. 3. Collaboration and License Agreement Detailed description of the contractual terms and our accounting for the agreement described below is included in our audited financial statements and notes in the 2023 Annual Report. During the six months ended June 30, 2024, we continued to perform under our exclusive global collaboration and license agreement (the “Collaboration Agreement”) with Jazz Pharmaceuticals Ireland Limited ("Jazz"), pursuant to which we recognized revenue utilizing the cost-to-cost input method, which best depicts the research and development services performed for the customer. Revenue from the transaction price was recognized over time as research and development services were performed. In June 2024, we executed a transfer agreement (the “Transfer Agreement”) to assign our rights in a development agreement with a contract manufacturer of our interferon alpha INDUKINE molecule JZP898 to Jazz. The execution of this Transfer Agreement was the last material performance obligation required of us under the Collaboration Agreement. As of the execution of the Transfer Agreement, we no longer have any material performance obligations under the Collaboration Agreement. As a result, during the three months ended June 30, 2024, all remaining deferred revenue related to the Collaboration Agreement has been recognized. The following table summarizes research and development costs incurred and revenue recognized in connection with our performance under the Collaboration Agreement: Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 (in thousands) (in thousands) Revenue recognized 1,143 8,081 1,885 12,545 Cost incurred 210 5,152 545 7,273 9 Table of Contents The following table presents changes in our contract liabilities during the six months ended June 30, 2024: Balance as of December 31, 2023 Additions Reductions Balance as of June 30, 2024 (in thousands) Contract liabilities: Deferred revenue $ 1,340 $ — $ ( 1,340 ) $ — Total contract liabilities $ 1,340 $ — $ ( 1,340 ) $ — All deferred revenue related to the Collaboration Agreement has been recognized as of June 30, 2024 Unbilled receivables related to the Collaboration Agreement of $ 0.2 million and $ 0.4 million are included within other receivables in the accompanying condensed consolidated balance sheets as of June 30, 2024 and December 31, 2023, respectively. Receivables related to the Collaboration Agreement of $ 0.3 million and $ 0.9 million are included within other receivables in the accompanying condensed consolidated balance sheets as of June 30, 2024 and December 31, 2023, respectively. Revenue recognized during the six months ended June 30, 2024 and 2023, includes $ 1.3 million and $ 5.3 million of revenue that was included in deferred revenue as of December 31, 2023 and 2022, respectively. At the end of each reporting period, we re-evaluate our estimate of the transaction price associated with the Collaboration Agreement and determine if variable consideration previously excluded from the transaction should be included in the transaction price based on changes in circumstances, if any. During the six months ended June 30, 2024 and 2023, we did not recognize any adjustment to the transaction price associated with variable consideration previously excluded from the transaction price. As of June 30, 2024, we have not received any royalty payments under the Collaboration Agreement. 4. 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, cash equivalents and restricted cash and cash equivalents on our condensed consolidated balance sheets as June 30, 2024 and December 31, 2023. 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 6, Term Loan) on our condensed consolidated balance sheets as June 30, 2024. We did not have any liabilities that are required to be measured at fair value on a recurring basis as of December 31, 2023. 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 and liabilities measured at fair value on a recurring basis as of June 30, 2024 were as follows: Level 1 Level 2 Level 3 Total (in thousands) Assets: Money market funds $ 129,881 $ — $ — $ 129,881 Total assets $ 129,881 $ — $ — $ 129,881 Liabilities: $ — $ — $ 2,841 $ 2,841 Derivative liability $ — $ — $ 2,841 $ 2,841 Assets measured at fair value on a recurring basis as of December 31, 2023 were as follows: Level 1 Level 2 Level 3 Total (in thousands) Assets: Money market funds $ 149,294 $ — $ — $ 149,294 Total assets $ 149,294 $ — $ — $ 149,294 There were no changes in valuation techniques during the three or six months ended June 30, 2024. 10 Table of Contents Derivative liabilities In May 2024, we entered into the K2HV Loan Agreement, as further described in Note 6, which provides up to $ 60.0 million principal in term loans. Pursuant to the terms of the K2HV Loan Agreement, the lenders thereto may elect, prior to the full repayment of the term loans, to convert up to $ 5.0 million of the outstanding principal of the term loans into shares of our common stock at a conversion price of the lesser of $ 6.3182 per share (the “Fixed Price Conversion”) and the lowest effective price per share of our first equity financing following the closing of the K2HV Loan Agreement (the “Variable Price Conversion”), subject to customary adjustments and 9.99 % and 19.99 % beneficial ownership limitations. The Fixed Price Conversion and Variable Price Conversion within the K2HV Loan Agreement are required to be bifurcated as a single compound embedded derivative at fair value, with subsequent changes in fair value recognized in the statements of operations. The following table reconciles the change in fair value of the conversion option derivative liability during the six months ended June 30, 2024 based on Level 3 inputs (in thousands): Six Months Ended June 30, 2024 Balance at December 31, 2023 $ — Fair value of embedded derivative at issuance of term loan 4,450 Change in fair value ( 1,609 ) Balance at June 30, 2024 $ 2,841 For the period ended June 30, 2024, the fair value of the conversion option derivative liability in the term loan has been estimated using the Monte Carlo model. A summary of the weighted-average significant unobservable inputs (Level 3 inputs) used in measuring the conversion option derivative liability in the term loan as of June 30, 2024 and May 2, 2024 (inception) is as follows: June 30, 2024 May 2, 2024 Stock Price $ 2.44 $ 6.08 Volatility 101.0 % 101.0 % Risk-free rate (continuous) 4.5 % 4.7 % Expected term (in years) 0.75 yrs 0.91 yrs Dividend yield (continuous) — % — % Success Payment Liability In April 2022, we entered into an amended and restated loan and security agreement (the “PWB Loan Agreement”) with Pacific Western Bank (“PWB”), as described below in Note 6. In conjunction with the PWB Loan Agreement, we became obligated to pay to PWB a one-time success payment of up to $ 1.6 million (the “Success Fee”) upon achieving certain conditions defined in the PWB Loan Agreement (the “Success Fee Event”). The Success Fee Event occurred during the second quarter of 2023, resulting in the immediate payment in full of the required Success Fee. Prior to the occurrence of the Success Fee Event, we recognized a success payment liability that was stated at fair value and was considered Level 3 because its fair value measurement was based, in part, on significant inputs not observed in the market. Upon completion of the Success Fee Event, we paid the total $ 1.6 million success payment and removed the corresponding success payment liability. We remeasured the success payment liability at each reporting date and immediately prior to the Success Fee Event. During the six months ended June 30, 2023, we recognized expense of $ 1.0 million associated with the change in the fair value of the success payment liability which is included in change in fair value of derivative liability in the accompanying condensed consolidated statements of operations. We had no outstanding obligation associated with the Success Fee as of June 30, 2024 or December 31, 2023. 11 Table of Contents 5. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities were comprised as follows: June 30, 2024 December 31, 2023 (in thousands) Contract research $ 2,845 $ 1,049 Manufacturing 2,418 2,772 Employee compensation and benefits 2,274 3,627 Professional fees 847 655 Accrued interest 258 310 Other 59 447 Total accrued expenses and other current liabilities $ 8,701 $ 8,860 6. Term Loan PWB Loan Agreement In April 2022, we entered into the PWB Loan Agreement with PWB and subsequently drew down an aggregate of $ 40.0 million in term loans. The term loans accrued interest on the outstanding daily balance at a floating annual rate equal to greater of: (i) 0.5 % above the prime rate then in effect or (ii) 4.5 %. If the prime rate changed throughout the term, the interest rate would be adjusted effective on the date of the prime rate change. All interest chargeable under the PWB Loan Agreement was computed on a 360-day year for the actual number of days elapsed, with interest payable monthly. We recognized interest expense related to the PWB Loan Agreement of $ 0.3 million and $ 0.9 million during the three months ended June 30, 2024 and 2023, respectively. In May 2024, we repaid all amounts outstanding under the PWB Loan Agreement, using $ 29.5 million in net loan proceeds received under the K2HV Loan Agreement, as described below at Note 6, together with $ 10.5 million in existing cash. We recognized a total loss on extinguishment of debt in the amount of $ 0.6 million in the six months ended June 30, 2024 primarily due to the write off of unamortized debt issuance costs. K2HV Loan Agreement 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; and Ankura Trust Company, LLC, as collateral trustee for the Lenders. The K2HV Loan Agreement provides 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 upon closing and $ 5.0 million from the second tranche commitment. A third tranche commitment of up to $ 10.0 million is available to be drawn at our option between January 1, 2025 and 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. A fourth tranche commitment of up to $ 20.0 million is available to be drawn down at our option through May 1, 2026 or if the third tranche is funded, May 1, 2027, subject to Lender’s review of our clinical, financial and operating plan and subject to the Lender’s consent in its sole and absolute discretion. The term loan matures on May 1, 2028, and we are obligated to make interest only payments for the first 24 months, or 36 months if the third tranche is funded, and then interest and equal principal payments each month thereafter through the maturity date. The term loan bears a variable interest rate equal to the greater of (i) 10.3 %, and (ii) the sum of (A) the prime rate last quoted in The Wall Street Journal (or a comparable replacement rate if The Wall Street Journal ceases to quote such rate) and (B) 1.8 %. We may prepay, at our option, all, but not less than all, of the outstanding principal balance and all accrued and unpaid interest with respect to the principal balance being prepaid of the term loans, subject to a prepayment premium to which the Lenders are entitled and certain notice requirements. We are obligated to pay a final fee equal to 6.95 % of the aggregate amount of the term loans funded, or the Final Fee, to occur upon the earliest of (i) the maturity date, (ii) the acceleration of the term loans, and (iii) the prepayment of the term loans. The Final Fee is being accreted to interest expense using the effective interest method over the life of the debt. The Lenders may elect prior to the full repayment of the term loans to convert up to $ 5.0 million of outstanding principal of the term loans into shares of our common stock, pursuant to the Fixed Price Conversion or the Variable Price Conversion, subject to customary adjustments and 9.99 % and 19.99 % beneficial ownership limitations. There will be no prepayment penalty for any principal amount converted into common stock. We determined that the Fixed Price Conversion and the Variable Price 12 Table of Contents Conversion within the K2HV Loan Agreement are required to be bifurcated as an embedded derivative under ASC 815 at fair value, and recorded as a discount on the debt on the date of issuance, with subsequent changes in fair value recognized in the accompanying consolidated statements of operations. See Note 4 for further discussion on this derivative instrument. As security for our obligations under the K2HV Loan Agreement, we granted the Lenders a first priority security interest on substantially all of our assets (other than intellectual property), subject to certain exceptions. The K2HV Loan Agreement contains customary representations and warranties, events of default and affirmative and negative covenants, including covenants that limit or restrict our ability to, among other things, dispose of assets, make changes to the our business, management, ownership or business locations, merge or consolidate, incur additional indebtedness, incur additional liens, pay dividends or other distributions or repurchase equity, make investments, and enter into certain transactions with affiliates, in each case subject to certain exceptions. Upon the occurrence of an event of default, a default interest rate of an additional 5.0 % per annum may be applied to the outstanding loan balances, and the Lenders may declare all outstanding obligations immediately due and payable and exercise all of their rights and remedies as set forth in the K2HV Loan Agreement and under applicable law. As of June 30, 2024, we are in compliance with all covenants. Subject to certain conditions, we granted the Lenders the right, prior to repayment of the term loans, to invest up to $ 5.0 million in the aggregate in future offerings of capital stock, at market terms, subject to certain exceptions and conditions. We incurred debt issuance costs of $ 0.7 million in connection with the term loans, composed of the facility fee of $ 0.4 million and other expenses paid to the Lenders of $ 0.2 million and external legal fees of $ 0.1 million. These debt issuance costs, together with fair value of the embedded derivative of $ 4.5 million , resulted in a debt discount of $ 5.1 million which is being amortized to interest expense over the term of the K2HV Loan Agreement using the effective interest method. The outstanding term loans payable consists of the following: June 30, 2024 (in thousands) Term loans $ 30,000 Unamortized debt discount ( 4,837 ) Total debt, long-term $ 25,163 The following table provides the components of interest expense related to the K2HV Loan Agreement: Three Months Ended June 30, 2024 Six Months Ended June 30, 2024 (in thousands) Interest expense based on coupon interest rate ( 10.3 %) of outstanding term loans $ 515 $ 515 Accretion of debt discount and Final Fee ( 8.94 %) 285 285 Total interest expense on effective rate ( 19.24 %) $ 800 $ 800 The following table presents the total principal payments and Final Fee schedules to become due during each of the years ended December 31: Principal Payments and Final Fee (in thousands) 2024 (remaining as of June 30, 2024) $ — 2025 — 2026 9,600 2027 14,400 2028 8,085 Total principal payments and Final Fee $ 32,085 13 7. 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, 2024, 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”), formerly known as SVB Securities LLC, pursuant to which we may 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. On February 9, 2024, we filed a prospectus supplement (the “Prospectus Supplement”) under our shelf registration statement for the offer and sale of shares of our common stock having an offering price of up to an additional $ 25.0 million in the ATM Offering. Following our filing of the Prospectus Supplement, we are now entitled to offer and sell shares of our common stock with an aggregate offering price of up to $ 75.0 million pursuant to the Sales Agreement. During the six months ended June 30, 2024, we sold 4,342,320 shares of our common stock at an average price of $ 5.11 per share for net proceeds of $ 21.1 million after deducting sales commissions and offering expenses. During the six months ended June 30, 2023, we sold 4,096,281 shares of our common stock at an average price of $ 2.36 per share for net proceeds of $ 9.3 million after deducting sales commissions and offering expenses. We have reserved shares of common stock for issuance as follows: As of June 30, As of December 31, 2024 2023 Shares reserved for exercises of outstanding stock options 7,510,033 5,700,070 Shares reserved for vesting of restricted stock units 150,000 361,500 Shares reserved for exercises of warrants 58,904 58,904 Shares reserved for future issuance under the 2021 Employee Stock Purchase Plan 471,933 507,113 Shares reserved for future issuance under the 2021 Stock Incentive Plan 2,050,950 1,911,660 Shares reserved for future issuance as part of K2HV conversion feature 791,364 — Total shares reserved for future issuance 11,033,184 8,539,247 Preferred Stock We are authorized to issue 5,000,000 shares of undesignated preferred stock in one or more series. As of June 30, 2024, no shares of preferred stock were issued or outstanding. 8. Stock-based Compensation 2017 Stock Incentive Plan In December 2017, we adopted the 2017 Stock Incentive Plan (as amended and restated, the “2017 Plan”), under which we could grant incentive stock options (“ISOs”), non-qualified stock options, restricted stock awards (“RSAs”), restricted stock units (“RSUs”), stock appreciation rights and other stock-based awards to eligible employees, officers, directors and consultants. The terms of stock options and RSAs, including vesting requirements, were determined by our board of directors, subject to the provisions of 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 (“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 ISOs, non-qualified stock options, RSAs, 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 the completion of the IPO, and (iii) 477,725 shares of unvested restricted stock 14 Table of Contents subject to repurchase by us that may become issuable under the 2021 Plan following such repurchase. The 2021 Plan also provides that an additional number of shares will be added annually to the shares authorized for issuance under the 2021 Plan on the first day of each fiscal year, beginning with the fiscal year ended December 31, 2022 and continuing until, and including, the fiscal year ending December 31, 2031. The number of shares added each year will be equal to the lesser of (i) 5 % of the number of outstanding common stock on such date and (ii) such amount as determined by our board of directors. As of June 30, 2024, a total of 4,911,502 additional shares have been added to the total shares authorized for issuance under the 2021 Plan in accordance with these terms. 2021 Employee Stock Purchase Plan The 2021 ESPP permits eligible employees to purchase shares of our common stock at a discount and consists of consecutive six-month offering periods, each containing a single six-month purchase period. On the first day of each offering period, each employee who is enrolled in the 2021 ESPP will automatically receive an option to purchase up to a whole number of shares of our common stock. The purchase price of each of the shares purchased, in a given purchase period, will be equal to 85 % of the lesser of the closing price of a share of our common stock on (i) the first day of the offering period, or (ii) the last day of the offering period. During the six months ended June 30, 2024 and 2023, 35,180 shares and 28,739 shares, respectively, of our common stock were purchased by participants of the 2021 ESPP. Stock-Based Compensation Expense Total stock-based compensation expense recognized in the condensed consolidated statements of operations was as follows: Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 (in thousands) Research and development $ 1,516 $ 1,019 $ 2,698 $ 2,039 General and administrative 1,086 911 2,209 1,999 Total stock-based compensation $ 2,602 $ 1,930 $ 4,907 $ 4,038 RSA Activity We may, at our discretion, repurchase unvested shares of restricted stock issued pursuant to the 2017 Plan at the initial purchase price if the employees or non-employees terminate their service relationship with us. The shares are recorded in stockholders’ deficit as they vest. As of December 31, 2023, all RSAs granted to employees or non-employees had become fully vested or had been previously forfeited. No RSAs were granted during the six months ended June 30, 2024. Accordingly, we had no unrecognized stock-based compensation expense related to unvested RSAs as of June 30, 2024. The aggregate fair value of RSAs that vested during the three and six months ended June 30, 2023, based upon the fair values of the stock underlying the RSAs on the date of vesting, was $ 0.1 million and $ 0.2 million, respectively. RSU Activity We have granted RSUs to our employees under the 2021 Plan. The following table summarizes RSU activity during the six months ended June 30, 2024: Shares/Units Weighted-Average Grant Date Fair Value Per Share (in thousands) Unvested at December 31, 2023 361,500 $ 3.92 Granted — $ — Vested ( 211,500 ) $ 4.97 Forfeited — $ — Unvested at June 30, 2024 150,000 $ 2.45 As of June 30, 2024, we had unrecognized stock-based compensation expense related to unvested RSUs of $ 0.2 million, which we expect to recognize over a weighted-average period of approximately 0.4 years. 15 Table of Contents The aggregate fair value of RSUs that vested during the three and six months ended June 30, 2024 , was $ 0.7 million based upon the fair value of the stock underlying the RSUs on the day of vesting. No RSUs vested during the three and six months ended June 30, 2023. Stock Option Activity During the year ended December 31, 2022, we granted performance-based stock options to certain executive officers for the purchase of an aggregate of 883,352 shares of common stock with a grant date fair value of $ 3.36 per share. These stock options would have vested only upon achievement of specified performance targets related to certain business objectives on or before December 31, 2023. As of June 30, 2023, none of these options were vested because none of the specified performance targets had been achieved. Because achievement of the specified performance targets was not deemed probable as of June 30, 2023, we did no t record any expense for these stock options during the three or six months ended June 30, 2023. As of December 31, 2023, the specified performance targets had not been achieved, and accordingly, all outstanding performance-based stock options expired without vesting. No additional performance-based stock options have been granted during the three or six months ended June 30, 2024. The fair value of stock options granted during the three and six months ended June 30, 2024 and 2023 was calculated on the date of grant using the following weighted-average assumptions: Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 Risk-free interest rate 4.5 % 3.8 % 4.0 % 3.9 % Expected term (in years) 5.5 5.7 6.0 6.0 Expected annual dividend yield — % — % — % — % Expected volatility 92.6 % 82.6 % 92.6 % 82.6 % Using the Black-Scholes option pricing model, the weighted-average grant date fair value of stock options granted during the three months ended June 30, 2024 and 2023 was $ 3.68 and $ 2.24 per share, respectively. Using the Black-Scholes option pricing model, the weighted-average grant date fair value of stock options granted during the six months ended June 30, 2024 and 2023 was $ 3.60 and $ 1.55 per share, respectively. The following table summarizes stock option activity during the six months ended June 30, 2024: Options Outstanding Number of Options Weighted-Average Exercise Price per Share Weighted-Average Remaining Contractual Life (in years) Aggregate Intrinsic Value (in millions) Outstanding at December 31, 2023 5,700,070 $ 6.89 Granted 2,205,112 $ 4.66 Exercised ( 6,099 ) $ 2.05 Cancelled ( 389,050 ) $ 5.06 Outstanding at June 30, 2024 7,510,033 $ 6.33 7.85 $ 0.8 Exercisable at June 30, 2024 4,100,266 $ 7.25 7.09 $ 0.5 The aggregate intrinsic fair value of stock options exercised during the three and six months ended June 30, 2024 and 2023 was nominal for each period. As of June 30, 2024, we had unrecognized stock-based compensation expense related to unvested stock options of $ 12.4 million, which we expect to recognize over a weighted-average period of approximately 2.5 years. 9. Related Parties In May 2022, we entered into a sublease agreement with Crossbow Therapeutics, Inc. (“Crossbow”), for which entities affiliated with MPM Capital (“MPM Capital”) are also beneficial owners, to sublease the entirety of our office and laboratory space in Cambridge, Massachusetts. Luke Evnin, Ph.D., the chair of our board of directors, co-founded MPM Capital and serves as Managing Director of MPM Capital. Briggs Morrison, who serves on our board of directors, serves as Executive Partner of MPM Capital and Chief Executive Officer of Crossbow. The term of the sublease agreement commenced in June 16 Table of Contents 2022 and ended in March 2024, with no option to extend. We received cash payments under the sublease of approximately $ 0.4 million during the six months ended June 30, 2024. In addition, we received $ 0.2 million from Crossbow in June 2022 as a security deposit, which was remitted to Crossbow following the termination of the sublease. 10. Net Loss Attributable to Common Stockholders per Share For purposes of the diluted net loss attributable to common stockholders per share calculation, outstanding stock options, unvested RSAs, unvested RSUs, conversion option derivative under the K2HV Loan Agreement, and warrants to purchase common stock are considered to be potentially dilutive securities, however the following outstanding shares of common stock equivalents were excluded from the calculation of diluted net loss attributable to common stockholders per share because their effect would be anti-dilutive: June 30, 2024 2023 Outstanding stock options 7,510,033 6,745,934 Unvested RSUs 150,000 316,500 Warrants to purchase common stock 58,904 58,904 Common stock to be issued under the 2021 ESPP 36,767 18,366 Total 7,755,704 7,139,704 Basic net loss per share is computed by dividing net loss by the weighted-average number of shares of common stock outstanding during the applicable period. In computing diluted net loss per share, only potential shares of common stock that are dilutive are included. We considered each issue or series of issues of potential shares of common stock separately when determining whether potential shares of common stock are dilutive or antidilutive. We made such determination in sequence from the most dilutive to the least dilutive and concluded that the conversion option derivative under the K2HV Loan Agreement is dilutive to net loss per share for the three and six months ended June 30, 2024. Pursuant to FASB ASC Topic 260, Earnings Per Share, we applied the if-converted method to determine the effect of the conversion option derivative under the K2HV Loan Agreement on the diluted earnings per share calculations. Pursuant to such method, we adjusted the numerator for the gain recognized during the period in net loss from the conversion option derivative under the K2HV Loan Agreement and the increased the denominator to include the number of additional shares of common stock that would have been outstanding if the conversion option derivative under the K2HV Loan Agreement were converted as of the beginning the period. Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 Numerator Net loss $ ( 17,249 ) $ ( 5,098 ) $ ( 33,442 ) $ ( 17,080 ) Less: Change in fair value of derivative liability ( 1,609 ) — ( 1,609 ) — Plus: Interest expense on converted term loan 120 — 120 — Adjusted net loss $ ( 18,738 ) $ ( 5,098 ) $ ( 34,931 ) $ ( 17,080 ) Denominator Weighted-average common stock outstanding, basic 43,521,406 35,557,701 42,564,342 35,173,327 Dilutive effect of common stock issuable from assumed conversion of convertible term loan 521,778 — 260,889 — Weighted-average common stock outstanding, diluted 44,043,184 35,557,701 42,825,231 35,173,327 Net loss per share Basic $ ( 0.40 ) $ ( 0.14 ) $ ( 0.79 ) $ ( 0.49 ) Diluted $ ( 0.43 ) $ ( 0.14 ) $ ( 0.82 ) $ ( 0.49 ) 17 Table of Contents