Quarterly Report for Quarter Ending September 30, 2024 (Form 10-Q)

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1. Nature of the Business and Basis of Presentation

Invivyd, Inc. (together with its consolidated subsidiaries, the "Company") is a biopharmaceutical company devoted to delivering protection from serious viral infectious diseases, beginning with SARS-CoV-2. The Company's proprietary INVYMAB™ platform approach combines state-of-the-art viral surveillance and predictive modeling with advanced antibody engineering. INVYMAB is designed to facilitate the rapid, serial generation of new monoclonal antibodies ("mAbs") to address evolving viral threats.

On March 22, 2024, the Company received emergency use authorization ("EUA") from the U.S. Food and Drug Administration ("FDA") for PEMGARDA™ (pemivibart) injection, for intravenous use, a half-life extended investigational mAb, for the pre-exposure prophylaxis (prevention) of COVID-19 in adults and adolescents (12 years of age and older weighing at least 40 kg) who have moderate-to-severe immune compromise due to certain medical conditions or receipt of certain immunosuppressive medications or treatments and are unlikely to mount an adequate immune response to COVID-19 vaccination. Recipients should not be currently infected with or have had a known recent exposure to an individual infected with SARS-CoV-2.

In July 2024, the Company submitted a request to the FDA to amend the EUA for PEMGARDA, for the treatment of mild-to-moderate symptomatic COVID-19 in certain immunocompromised patients. The submission utilizes a rapid immunobridging pathway previously aligned in principle with the FDA. The EUA amendment request is based on positive immunobridging analyses of pemivibart versus comparator mAbs and data from the Company's ongoing CANOPY Phase 3 clinical trial in participants with moderate-to-severe immune compromise. The COVID-19 treatment EUA request focuses on the critical treatment needs of people in the U.S. who have moderate-to-severe immune compromise and for whom alternative COVID-19 treatment options are not clinically appropriate or accessible.

PEMGARDA is the Company's first mAb in a planned series of innovative mAb candidates designed to keep pace with SARS-CoV-2 viral evolution. As the SARS-CoV-2 virus evolves over time, the Company anticipates leveraging its INVYMAB platform approach to periodically introduce new or engineered mAb candidates, an approach that would be analogous to the periodic updates made to influenza and COVID-19 vaccines. In January 2024, the Company nominated VYD2311, a next generation mAb candidate for COVID-19, as a drug candidate, and in September 2024, the Company announced dosing of the first participants in a Phase 1 clinical trial of VYD2311. VYD2311 is a mAb with high in vitro neutralization potency shown against prominent SARS-CoV-2 variants tested to date. The Phase 1 randomized, blinded, placebo-controlled clinical trial will evaluate escalating dosing as well as safety, tolerability, pharmacokinetics and immunogenicity of VYD2311 in healthy trial participants. The Phase 1 clinical trial is being conducted in Australia and will evaluate multiple dose levels of VYD2311 through various routes of administration, including exploration of intramuscular administration and subcutaneous administration, which are designed to be more system- and patient-friendly than intravenous administration. The Company expects preliminary data readouts from the Phase 1 clinical trial late in the fourth quarter of 2024 and anticipates additional clinical readouts from the VYD2311 program throughout 2025. Like pemivibart, VYD2311 was engineered from adintrevimab, the Company's investigational mAb that has a robust safety data package and demonstrated clinically meaningful results in global Phase 2/3 clinical trials for both the prevention and treatment of COVID-19.

In May 2024, the Company announced general alignment with the FDA on an expedient, repeatable immunobridging pathway to future potential EUAs for serial, novel mAbs for the prevention and treatment of symptomatic COVID-19. This pathway provides the Company with the opportunity to rapidly, efficiently, and durably deliver high value medicines that prevent and treat symptomatic COVID-19 in vulnerable populations. In addition to developing candidates for COVID-19, the Company expects to apply its INVYMAB platform approach to produce lead molecules for other viral diseases, such as influenza.

The Company was incorporated in the State of Delaware in June 2020. The Company operates as a hybrid company with employees working at its corporate headquarters in Waltham, Massachusetts and remotely. In June 2022, and subsequently amended in September 2022 and August 2024, the Company entered into a lease for dedicated laboratory and office space in Newton, Massachusetts for research and development purposes. In 2022, the Company expanded its research team to enable internal discovery and development of its mAb candidates, while continuing to leverage the Company's existing partnership with Adimab, LLC ("Adimab"). The Company is focused on antibody discovery and use of Adimab's platform technology while building its own internal capabilities. In addition, the Company performs research and development activities internally and engages third parties, including Adimab, to perform ongoing research and development and other services on its behalf.

The Company is subject to a number of risks and uncertainties common to companies in the biopharmaceutical industry, including, but not limited to, completing clinical trials, the ability to raise additional capital to fund operations, obtaining regulatory authorization or approval for product candidates, risks associated with market acceptance and commercialization of products, competition from other products, protection of proprietary intellectual property, compliance with government regulations, dependence on key personnel, the ability to attract and retain qualified employees, and reliance on third-party organizations for the discovery, manufacturing, clinical and commercial success of its product candidates.

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To date, the Company has received regulatory authorization for only one product candidate, PEMGARDA, which has not been approved, but has been authorized for emergency use by the FDA under an EUA, for pre-exposure prophylaxis of COVID-19 in certain adults and adolescent individuals (12 years of age and older weighing at least 40 kg). Beyond VYD222 (pemivibart) and VYD2311, all of the Company's other product candidates, other than adintrevimab, are currently in research development. The Company's additional product candidates require significant additional research and development efforts, including extensive clinical testing, and regulatory authorization or approval prior to potential commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and compliance-reporting capabilities. It is uncertain when, if ever, the Company will generate substantial revenue from product sales to be able to fund its operating expenses and capital requirements.

Substantial Doubt about Ability to Continue as a Going Concern

The accompanying condensed consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets, and the satisfaction of liabilities and commitments in the ordinary course of business. The Company has primarily funded its operations with proceeds from sales of convertible preferred stock, proceeds from the Company's initial public offering ("IPO") and net proceeds received from shares of common stock sold under the Sales Agreement (as defined below). In February 2024, the Company sold 9,000,000shares of its common stock under the Sales Agreement at an average price of $4.50per share for $39.3million in net proceeds. After receiving EUA in March 2024, the Company has also funded its operations from sales of PEMGARDA.

The Company has incurred losses and negative cash flows from operations since its inception, including a net loss of $151.5million for the nine months ended September 30, 2024. As of September 30, 2024, the Company had an accumulated deficit of $883.6million. The Company may continue to generate operating losses for the foreseeable future.

Based on current operating plans and excluding any contribution from future revenues or external financing, the Company will not have sufficient cash and cash equivalents to fund its operating expenses and capital requirements beyond one year from the issuance of these condensed consolidated financial statements, and therefore, the Company has concluded that there is substantial doubt about its ability to continue as a going concern.

The Company will require additional funding through a combination of contribution from revenues, equity offerings, government or private-party grants, debt financings or other capital sources, such as collaborations with other companies, strategic alliances or licensing arrangements to finance its future operations. The Company may not be able to obtain financing on acceptable terms, or at all, and the Company may not be able to enter into collaborations or other arrangements. The terms of any financing may adversely affect the holdings or rights of the Company's stockholders.

If the Company is unable to obtain sufficient capital, the Company will be forced to delay, reduce or eliminate some or all of its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects, or the Company may be unable to continue operations. Although management continues to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all. The accompanying condensed consolidated financial statements do not include any adjustments related to the recoverability and classification of assets or the amounts and classification of liabilities or any other adjustments that might be necessary should the Company be unable to continue as a going concern.

Basis of Presentation

The Company's condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America ("U.S. GAAP"). Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification ("ASC") and Accounting Standards Update ("ASU") of the Financial Accounting Standards Board ("FASB").

The accompanying condensed consolidated financial statements include the accounts of Invivyd, Inc. and its wholly owned subsidiaries, Invivyd Security Corporation, Invivyd Switzerland GmbH, and Invivyd Netherlands B.V. All intercompany accounts and transactions have been eliminated in consolidation. The Company views its operations and manages its business in one operating segment, which is the business of discovering, developing and commercializing differentiated products for the prevention and treatment of infectious diseases.

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normally included in the financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. These interim condensed consolidated financial statements should be read in conjunction with the Company's audited annual consolidated financial statements, and the notes thereto, as of and for the year ended December 31, 2023, which are included in the 2023 Form 10-K.

In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company's condensed consolidated financial position as of September 30, 2024 and December 31, 2023, the condensed consolidated results of operations for the three and nine months ended September 30, 2024 and 2023, the condensed consolidated cash flows for the three and nine months ended September 30, 2024 and 2023, and changes in stockholders' equity (deficit) for the three and nine months ended September 30, 2024 and 2023 have been made. The Company's condensed consolidated results of operations for the three and nine months ended September 30, 2024 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2024.

2. Summary of Significant Accounting Policies

As of September 30, 2024, the Company's significant accounting policies and estimates, which are detailed in the Company's Annual Report on Form 10-K for the year ended December 31, 2023, as filed with the U.S. Securities and Exchange Commission ("SEC") on March 28, 2024 (the "2023 Form 10-K") have not changed, except as discussed below.

Inventory is stated at the lower of cost or estimated net realizable value with cost determined on a first-in, first-out basis. Inventory costs include raw materials, third-party contract manufacturing, third-party packaging services, freight and overhead. The Company reduces its inventory to net realizable value for potentially excess, dated or obsolete inventory based on a quarterly assessment of the recoverability of its capitalized inventory. The Company periodically reviews inventory levels to identify what may expire prior to expected sale or has a cost basis in excess of its estimated realizable value and writes-down such inventories as appropriate as a component of costs of goods sold in the consolidated statements of operations and comprehensive loss.

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3. Fair Value Measurements

Fair Value Measurements

Certain assets of the Company are carried at fair value under U.S. GAAP. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

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The Company's cash equivalents are carried at fair value, determined according to the fair value hierarchy described above. The carrying values of the Company's accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities.

The money market funds were valued by the Company based on quoted market prices, which represent a Level 1 measurement within the fair value hierarchy.

There were no changes to the valuation methods during the three and nine months ended September 30, 2024 or 2023.

The Company evaluates transfers between levels at the end of each reporting period. There were notransfers into or out of Level 1, Level 2 or Level 3 fair value measurements during the three and nine months ended September 30, 2024or 2023.

4. Inventory

The Company did not have any inventory as of December 31, 2023.

5. Prepaid Expenses and Other Current Assets

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6. Accrued Expenses

7. License and Collaboration Agreements

Adimab Assignment Agreement

In July 2020, the Company entered into an Assignment and License Agreement with Adimab (the "Adimab Assignment Agreement"). Under the terms of the agreement, Adimab assigned to the Company all rights, title and interest in and to certain of its coronavirus-specific antibodies (each, a "CoV Antibody" and together, the "CoV Antibodies"), including modified or derivative forms thereof, and related intellectual property. In addition, Adimab granted to the Company a non-exclusive, worldwide, royalty-bearing, sublicensable license to certain of its platform patents and technology for the development, manufacture and commercialization of the CoV Antibodies and pharmaceutical products containing or comprising one or more CoV Antibodies (each, a "Product") for all indications and uses, with the exception of certain diagnostic uses and use as a research reagent (the "Field"). The Company is entitled to sublicense the assigned rights and licensed intellectual property solely with respect to any CoV Antibody or Product, subject to specified conditions of the agreement. The Company is obligated to use commercially reasonable efforts to achieve specified development and regulatory milestones for Products in certain major markets and to commercialize a product in any country in which the Company obtains marketing approval.

Pursuant to the terms of the Adimab Assignment Agreement, the parties will establish one or more work plans that set forth the activities to be performed under the agreement (each, a "Work Plan"), and each party is responsible for performing the obligations to which it is assigned under such Work Plans. Upon execution of the Adimab Assignment Agreement, the Company and Adimab agreed on an initial Work Plan that outlined the services that will be performed commencing at inception of the arrangement. The Company is obligated to pay Adimab quarterly for its services performed under each Work Plan at a specified full-time equivalent rate. Otherwise, the Company is solely responsible for the development, manufacture and commercialization of the CoV Antibodies and associated Products at its own cost and expense. The Company is solely responsible for preparing and submitting all investigational new drug applications, new drug applications, biologics license applications and other regulatory filings for the CoV Antibodies and Products in the Field, and for obtaining and maintaining all marketing approvals for Products in the Field, at its sole expense. Additionally, the Company has the sole right to prosecute, maintain, enforce and defend patents covering the CoV Antibodies and Products, all at its own expense.

Amounts paid with respect to services performed by Adimab on the Company's behalf under the Adimab Assignment Agreement are recognized as research and development expense as such amounts are incurred. During the three and nine months ended September 30, 2024 and 2023, the Company did not recognize any research and development expense with respect to services performed by Adimab on the Company's behalf under the Adimab Assignment Agreement. Please refer to Note 15 for additional information.

The Company is obligated to pay Adimab up to $16.5million upon the achievement of specified development and regulatory milestones for the first Product under the agreement that achieves such specified milestones and up to $8.1million upon the achievement of specified development and regulatory milestones for the second Product under the agreement that achieves such specified milestones. The maximum aggregate amount of milestone payments payable under the agreement for any and all Products is $24.6million, of which a total of $11.1million has been achieved and paid as of September 30, 2024; however, milestone payments do not accrue for certain in vitro diagnostic devices consisting of or containing CoV Antibodies.

In March 2023, the Company achieved the first specified milestone for the second product candidate under the Adimab Assignment Agreement upon dosing of the first subject in a Phase 1 clinical trial evaluating VYD222, which obligated the Company to make a $0.4million milestone payment to Adimab, which was paid in May 2023. In September 2023, the Company achieved specified milestones for the second product candidate under the Adimab Assignment Agreement upon dosing of the first subject in a pivotal clinical trial evaluating VYD222, which obligated the Company to make a $3.2million milestone payment to Adimab, which was paid in October 2023. The next potential milestone under the Adimab Assignment Agreement is a low single-digit million-dollar regulatory milestone, which was not considered probable under U.S. GAAP and therefore, no expense was recognized as of September 30, 2024.

During both the three and nine months ended September 30, 2024, the Company did not recognize any in-process research and development ("IPR&D") expense with respect to contingent consideration payable under the Adimab Assignment Agreement. During the three and nine months ended September 30, 2023, the Company recognized $3.2and $3.6million, respectively, of IPR&D expense

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with respect to contingent consideration payable under the Adimab Assignment Agreement. Except for milestone payments of $11.1million incurred through December 31, 2023, no other milestone payments have been paid to or have been earned by Adimab through September 30, 2024.

The Company is obligated to pay Adimab royalties of a mid-single-digit percentage based on net sales of any Products, beginning upon the first commercial sale of a Product in accordance with the Adimab Assignment Agreement. The royalty rate is subject to reductions specified under the agreement. Royalties are due on a Product-by-Product and country-by-country basis beginning upon the first commercial sale of each Product and ending on the later of (i) 12 years after the first commercial sale of such Product in such country and (ii) the expiration of the last valid claim of a patent covering such Product in such country (the "Royalty Term"). During both the three and nine months ended September 30, 2024, the Company expensed $0.5million of royalties and reserves all rights under the Adimab Assignment Agreement and the applicable law. During both the three and nine months ended September 30, 2023, the Company did not expense any royalties. In addition, the Company is obligated to pay Adimab royalties of a specified percentage in the range of 45% to 55% of any compulsory sublicense consideration received by the Company in lieu of certain royalty payments.

Unless earlier terminated, the Adimab Assignment Agreement remains in effect until the expiration of the last-to-expire Royalty Term for any and all Products. The Company may terminate the agreement at any time for any or no reason upon advance written notice to Adimab, or in the event of a material breach by Adimab that is not cured with specific periods. Adimab may only terminate the agreement for an uncured material breach by the Company for its due diligence obligation or a payment obligation. Upon any termination of the agreement prior to its expiration, all licenses and rights granted pursuant to the arrangement will automatically terminate and revert to the granting party and all other rights and obligations of the parties will terminate.

The Company concluded that the Adimab Assignment Agreement represented an asset acquisition of IPR&D assets with no alternative future use. The arrangement did not qualify as a business combination because substantially all of the fair value of the assets acquired was concentrated in a single asset.

Adimab Collaboration Agreement

In May 2021, the Company entered into a Collaboration Agreement with Adimab, as amended in November 2022 and September 2023 (the "Adimab Collaboration Agreement"), for the discovery and optimization of proprietary antibodies as potential therapeutic product candidates. Under the Adimab Collaboration Agreement, the Company and Adimab could collaborate on research programs for a specified number of targets selected by the Company within a specified time period. Under the Adimab Collaboration Agreement, Adimab granted the Company a worldwide, non-exclusive license to certain of its platform patents and technology and antibody patents to perform the Company's responsibilities during the ongoing research period and for a specified evaluation period thereafter (the "Evaluation Term"). In addition, the Company granted Adimab a license to certain of the Company's patents and intellectual property solely to perform Adimab's responsibilities under the research plans. Under the Adimab Collaboration Agreement, the Company has an exclusive option, on a program-by-program basis, to obtain licenses and assignments to commercialize selected products containing or comprising antibodies directed against the applicable target, which option may be exercised upon the payment of a specified option fee for each program. Upon exercise of an option by the Company, Adimab will assign to the Company all right, title and interest in the antibodies of the optioned research program and will grant the Company a worldwide, royalty-free, fully paid-up, non-exclusive, sublicensable license under the Adimab platform technology for the development, manufacture and commercialization of the antibodies for which the Company has exercised its options and products containing or comprising those antibodies. The Company is obligated to use commercially reasonable efforts to develop, seek marketing approval for, and commercialize one product that contains an antibody discovered in each optioned research program.

The Company agreed to pay Adimab a quarterly fee of $1.3million, which could be cancelled at the Company's option at any time. For so long as the Company was paying such quarterly fee (or earlier if (i) the Company experienced a change of control after the third anniversary of the Adimab Collaboration Agreement or (ii) Adimab owned less than a specified percentage of the Company's equity), Adimab and its affiliates agreed not to assist or direct certain third parties to discover or optimize antibodies intended to bind to coronaviruses or influenza viruses. Under the Adimab Collaboration Agreement, the Company could also elect to decrease the scope of Adimab's exclusivity obligations and obtain a corresponding decrease in the quarterly fee. In December 2023, the Company elected to decrease the scope of Adimab's exclusivity obligations to cover only coronaviruses andobtained a corresponding decrease in the quarterly fee. Effective January 2024, the Company became obligated to pay Adimab a quarterly fee of $0.6million. During the three and nine months ended September 30, 2024, the Company recognized $0.6million and $1.8million, respectively, of research and development expense related to the quarterly fee. During the three and nine months ended September 30, 2023, the Company recognized $1.3million and $3.9million, respectively, of research and development expense related to the quarterly fee.

For each agreed upon research program that is commenced, the Company is obligated to pay Adimab quarterly for its services performed during a given research program at a specified full-time equivalent rate; a discovery delivery fee of $0.2million; and an optimization completion fee of $0.2million. For each option exercised by the Company to commercialize a specific research program, the Company is obligated to pay Adimab an exercise fee of $1.0million. Amounts paid with respect to services performed by Adimab on the Company's behalf in each of the research programs under the Adimab Collaboration Agreement are recognized as research and development expense as such amounts are incurred and services are rendered. During both the three and nine months ended

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September 30, 2024, the Company did not recognize any research and development expense with respect to services performed by Adimab on the Company's behalf under the Adimab Collaboration Agreement. During the three and nine months ended September 30, 2023, the Company recognized $0.1million and $0.5million, respectively, of research and development expense with respect to services performed by Adimab on the Company's behalf under the Adimab Collaboration Agreement. During the three and nine months ended September 30, 2024, the Company did not recognize any IPR&D expense related to drug delivery fees, optimization completion fees or option exercise fees. During both the three and nine months ended September 30, 2023, the Company recognized $1.0million, $0.2million, and $0.2million of IPR&D expense related to an option exercise fee, a drug delivery fee and an optimization completion fee, respectively. Please refer to Note 15 for additional information.

The Company is obligated to pay Adimab up to $18.0million upon the achievement of specified development and regulatory milestones for each product under the Adimab Collaboration Agreement that achieves such milestones. The next potential milestone under the Adimab Collaboration Agreement is a low single-digit million-dollar clinical milestone, which was not considered probable under U.S. GAAP and therefore, no expense was recognized as of September 30, 2024. The Company is also obligated to pay Adimab royalties of a mid-single-digit percentage based on net sales of any product under the Adimab Collaboration Agreement, subject to reductions for third-party licenses. The royalty term will expire for each product on a country-by-country basis upon the later of (i) 12 years after the first commercial sale of such product in such country and (ii) the expiration of the last valid claim of any patent claiming composition of matter or method of making or using any antibody identified or optimized under the Adimab Collaboration Agreement in such country.

In addition, the Company is obligated to pay Adimab for Adimab's performance of certain validation work with respect to certain antigens acquired from a third party. In consideration for this work, the Company is obligated to pay Adimab royalties of a low single-digit percentage based on net sales of products that contain such antigens for the same royalty term as antibody-based products, but the Company is not obligated to make any milestone payments for such antigen products. Through September 30, 2024, no royalty payments have been paid to or have been earned by Adimab under the Adimab Collaboration Agreement.

The Adimab Collaboration Agreement will expire (i) if the Company does not exercise any option, upon the conclusion of the last Evaluation Term for the research programs, or (ii) if the Company exercises an option, on the expiration of the last royalty term for a product in a particular country, unless the agreement is earlier terminated. The Company may terminate the Adimab Collaboration Agreement at any time upon advance written notice to Adimab. In addition, subject to certain conditions, either party may terminate the Adimab Collaboration Agreement in the event of a material breach by the other party that is not cured within specified periods.

The Company concluded that the Adimab Collaboration Agreement represented an asset acquisition of IPR&D with no alternative future use. Therefore, payments made by the Company to Adimab for milestones achieved will be recognized as IPR&D expense in the related period in which the services are performed or the related milestone is considered probable of achievement. Amounts paid with respect to services performed by Adimab on the Company's behalf under the Adimab Collaboration Agreement are recognized as research and development expense as such amounts are incurred and services are rendered. Please refer to Note 15 for additional information.

Adimab Platform Transfer Agreement

In September 2022 (the "Adimab Platform Transfer Agreement Effective Date"), the Company entered into a Platform Transfer Agreement with Adimab (the "Adimab Platform Transfer Agreement") under which the Company was granted the right under certain intellectual property of Adimab to practice certain elements of Adimab's platform technology, including B-cell cloning using Adimab's proprietary yeast cell lines and other antibody optimization libraries, trade secrets, protocols and software of Adimab, to discover, engineer and optimize antibodies. The Company does not have access to Adimab's proprietary discovery libraries. The Company was also granted the right under certain intellectual property of Adimab to research, develop, make, sell and exploit such antibodies and products containing such antibodies. The Adimab platform has been transferred to the Company in accordance with the terms of the Adimab Platform Transfer Agreement. In September 2022, the Company recognized $3.0million as IPR&D expense in connection with the upfront consideration payable for the rights assigned pursuant to the Adimab Platform Transfer Agreement.

The Company is obligated to pay Adimab an annual fee of single digit millions on each of the first four anniversaries of the Adimab Platform Transfer Agreement Effective Date, which allows the Company to receive material improvements to the platform technology, including materially improved antibody optimization libraries, updates that provide new functionality to the platform, and software upgrades, from Adimab through June 2027. The first annual fee became due in September 2023 and was paid in October 2023. During the three and nine months ended September 30, 2024, the Company recognized a portion of the annual fees as research and development expense. Beginning in July 2027 and ending in June 2042, unless terminated earlier, the Company has the option to receive additional material improvements to the platform technology from Adimab, subject to a commercially reasonable fee to be negotiated by the parties.

The Company is obligated to pay Adimab up to $9.5million upon the achievement of specified development and regulatory milestones for each product under the Adimab Platform Transfer Agreement that achieves such milestones. The next potential milestone under the Adimab Platform Transfer Agreement is a mid-six-digit dollar preclinical milestone, which was not considered probable under U.S. GAAP and therefore, no expense was recognized as of September 30, 2024.

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In addition, the Company is obligated to pay Adimab royalties of a low single-digit percentage based on net sales of products containing an antibody discovered, engineered or optimized using Adimab's platform technology, subject to reductions specified under the Adimab Platform Transfer Agreement. Royalties are due on a product-by-product and country-by-country basis. The royalty term will expire for each product on a country-by-country basis upon the later of (i) 12 years after the first commercial sale of such product in such country and (ii) the expiration of the last valid claim of a program antibody patent for covering the program antibody contained in such product in such country. Through September 30, 2024, no royalty payments have been paid to or have been earned by Adimab under the Adimab Platform Transfer Agreement.

The Company may terminate the Adimab Platform Transfer Agreement at any time upon advance written notice to Adimab. In addition, subject to certain conditions, either party may terminate the Adimab Platform Transfer Agreement in the event of a material breach by the other party that is not cured within specified periods or in connection with the other party's insolvency.

The Company concluded that the Adimab Platform Transfer Agreement represented an asset acquisition of IPR&D with no alternative future use. Therefore, payments made by the Company to Adimab for milestones achieved will be recognized as IPR&D expense in the related period in which the services are performed or the related milestone is considered probable of achievement. Amounts paid with respect to the annual material improvement fees are recognized as research and development expense as such amounts are incurred. Please refer to Note 15 for additional information.

WuXi Biologics Cell Line License Agreement

In December 2020, as amended in February 2023 and March 2024, the Company entered into a Cell Line License Agreement with WuXi Biologics (Hong Kong) Limited ("WuXi Biologics") (the "Cell Line License Agreement"), under which WuXi Biologics granted to the Company a non-exclusive, non-transferable, worldwide, royalty-bearing, sublicensable license to certain of its intellectual property, including certain patent rights associated with a proprietary cell line developed by WuXi Biologics for the exploitation of certain recombinant antibodies developed using such proprietary cell line (each, a "Licensed Product"). Each Licensed Product generated under the arrangement will be produced from a transformed or transfected version of the proprietary cell line derived by WuXi Biologics (each of such transformed or transfected cell lines, a "Licensed Cell Line").

In December 2020, the Company recognized an upfront fee of $0.2million upon completion of cell bank generation for the first Licensed Cell Line created under the Cell Line License Agreement.

The Company is also obligated to pay royalties in the range of less than 1.0% to WuXi Biologics based on net sales of any Licensed Products manufactured by the Company or a third party on its behalf. However, if the Company uses WuXi Biologics to manufacture all of its commercial supplies for Licensed Products, no royalties would be owed by the Company to WuXi Biologics for net sales of Licensed Products. The Company has an option to buy out its royalty obligations on a Licensed Cell Line-by-Licensed Cell Line basis by making a one-time payment in the low eight-figures to WuXi Biologics. Royalties are due on a Licensed Product-by-Licensed Product basis commencing on the date of the first commercial sale of the applicable product and continuing for so long as the Company commercializes Licensed Products or, if earlier, until the Company exercises its option to buy out the royalty obligations. Through September 30, 2024, noroyalties had become due to WuXi Biologics.

The Cell Line License Agreement remains in effect until it is terminated. The Company may terminate the Cell Line License Agreement at any time with notice to WuXi Biologics. WuXi Biologics may terminate the Cell Line License Agreement in the event the Company fails to make a payment when due under the Cell Line License Agreement and such non-payment is not cured within a specified period after notice. Either party may terminate the Cell Line License Agreement in the event of a material breach by the other party that is not cured within a specified period after notice. Upon termination of the Cell Line License Agreement, the license conveyed by WuXi Biologics to the Company will continue in full force and effect with respect to all Licensed Products manufactured using the Licensed Cell Line already generated under the Cell Line License Agreement, provided that the Company continues to pay its royalty obligations, if any.

8. Population Health Partners, L.P.

In November 2022 (the "PHP Effective Date"), the Company entered into a Master Services Agreement with Population Health Partners, L.P. ("PHP"), pursuant to which PHP agreed to provide services and create deliverables for the Company as agreed between the Company and PHP and set forth in one or more work orders under such agreement (the "PHP MSA"). The term of the PHP MSA commenced on the PHP Effective Date for an initial term of one year. The PHP MSA renewed for subsequent periods, until terminated in accordance with its terms. The PHP MSA was terminated effective in July 2024. On the PHP Effective Date, the Company and PHP

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entered into the first work order under the PHP MSA (the "PHP Work Order"), pursuant to which PHP agreed to advise and counsel the Company regarding clinical development and regulatory matters with respect to the Company's product candidates. The PHP Work Order was effective for six months from the PHP Effective Date and terminated in accordance with its terms in May 2023. The PHP MSA contained customary confidentiality provisions and representations and warranties of the parties, as well as mutual non-solicitation of certain employees during the term of the PHP MSA and for a period of one year thereafter.

As compensation for the services and deliverables under the PHP Work Order, the Company paid PHP a cash fee of $0.5million per month during the term of the PHP Work Order for an aggregate fee of $3.0million (the "Aggregate Fee").

During the three and nine months ended September 30, 2024, the Company did not recognize any research and development expense related to the cash compensation paid to PHP. During the three and nine months ended September 30, 2023, the Company recognized $0and $2.3million, respectively, of research and development expense related to the cash compensation paid to PHP.Please refer to Note 15 for additional information.

In addition to the cash compensation, on the PHP Effective Date, the Company issued a warrant to purchase shares of the Company's common stock to PHP (the "PHP Warrant"). The exercise price of the PHP Warrant is $3.48per share of the Company's common stock, which was equal to the Nasdaq official closing price of a share of the Company's common stock on the trading day immediately prior to the PHP Effective Date. The PHP Warrant is exercisable for up to an aggregate of 6,824,712shares of the Company's common stock, and vests in three separate tranches as follows:

For purposes of the PHP Warrant, the term "Market Capitalization" means, with respect to a particular trading day, the total value of the outstanding shares of the Company's common stock on such date, calculated by multiplying the Company's volume weighted-average price for the ten (10) trading days immediately preceding such date by the Company's total number of outstanding shares of the Company's common stock as reflected in (i) the Company's most recent periodic or annual report filed with the SEC (e.g., Annual Report on Form 10-K or Quarterly Report on Form 10-Q), as the case may be, (ii) a more recent public announcement by the Company or (iii) a more recent written notice by the Company or the Company's transfer agent setting forth the number of shares of the Company's common stock outstanding.

The PHP Warrant is exercisable for ten years from the PHP Effective Date with respect to the vested portion(s) of the PHP Warrant. The PHP Warrant may be exercised by cash exercise or, at the election of PHP, by means of "cashless exercise" pursuant to a formula set forth in the PHP Warrant. The Company also granted PHP certain "piggyback" registration rights requiring the Company to register any shares of the Company's common stock underlying the PHP Warrant for resale with the SEC, subject to the Company's existing obligations under that certain Second Amended and Restated Investors' Rights Agreement, dated April 16, 2021, by and among the Company and the investors party thereto, which registration rights PHP exercised in January 2024.

Upon the consummation of a fundamental transaction of the Company (as defined in the PHP Warrant) on or prior to November 15, 2028, all of the shares underlying the PHP Warrant would become immediately vested and exercisable; upon the consummation of a fundamental transaction of the Company after November 15, 2028 but on or prior to November 15, 2029, the shares underlying the second and third tranches of the PHP Warrant would become immediately vested and exercisable; and upon the consummation of a fundamental transaction of the Company after November 15, 2029 but on or prior to November 15, 2030, the shares underlying the third tranche of the PHP Warrant would become immediately vested and exercisable.

Refer to Note 11 for additional information on the PHP Warrant.

Tamsin Berry, a member of the Company's board of directors, is a Limited Partner of PHP.

Operating Lease Commitments

In September 2021, the Company entered into a five-yearnoncancelable facilities lease agreement for approximately 9,600square feet of office space in Waltham, Massachusetts, which provides for monthly rental payments, including base rent charges of $0.4million per year, subject to periodic rent increases, and the Company's proportionate share of operating expenses.

In June 2022, the Company entered into a two-year noncancelable agreement for dedicated laboratory and office space in Newton, Massachusetts (the "Newton, MA Lease"), which was amended in September 2022. Pursuant to the amended Newton, MA Lease, the

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Company entered into a two-year noncancelable agreement for new dedicated laboratory and office space in Newton, Massachusetts, on the same campus as, and in lieu of, the space leased under the original lease. The Company took occupancy of the new dedicated laboratory and office space in December 2022. The amended Newton, MA Lease provided for monthly rental payments, including base rent charges of $1.3million per year. In August 2024, the Newton, MA Lease was further amended to extend the lease through November 2025,with an option to further extend the lease for an additional twenty-five months or continue the lease on a month-to-month basis after completion of the term ending in November 2025.

As of September 30, 2024, the Company's operating leases were measured using a weighted-average incremental borrowing rate of 6.0% over a weighted-average remaining lease term of 1.1years.

As of September 30, 2023, the Company's operating leases were measured using a weighted-average incremental borrowing rate of 6.0% over a weighted-average remaining lease term of 2.0years.

The total operating liabilities are presented on the Company's condensed consolidated balance sheet based on maturity dates. $1.4million is classified under "operating lease liabilities, current" for the portion due within twelve months, and $0.2million is classified under "operating lease liabilities, non-current".

License Agreements

The Company has entered into license agreements with Adimab and WuXi Biologics (see Note 7).

Other Agreements

In November 2022, the Company entered into the PHP MSA (see Note 8). Concurrently with the PHP MSA, the Company entered into the PHP Work Order, pursuant to which PHP agreed to advise and counsel the Company regarding clinical development and regulatory matters with respect to its product candidates. The PHP Work Order was effective for six months from November 2022 and terminated in accordance with its terms in May 2023. As compensation for the services and deliverables under the PHP Work Order, the Company recognized research and development expense of $0.5million per month during the term of the PHP Work Order for an Aggregate Fee of $3.0million.

Manufacturing Agreements

In December 2020, the Company entered into a Commercial Manufacturing Services Agreement with WuXi Biologics, which was amended and restated in August 2021 and further amended and restated in September 2023 (as amended and restated, the "Commercial Manufacturing Agreement"). The Commercial Manufacturing Agreement outlines the terms and conditions under which WuXi Biologics manufactures drug substance and drug product for commercial use.

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Through September 30, 2024, the Company committed to noncancelable purchase obligations related to commercial drug substance and drug product manufacturing under the Commercial Manufacturing Agreement. As of September 30, 2024, the total remaining contractually binding commercial drug substance and drug product purchase obligations due to WuXi Biologics was $38.3million, which is expected to be paid in 2024 and 2025. As of September 30, 2024, $36.5million related to the contractually binding commercial drug substance and drug product batches was included in accounts payable and accrued expenses, which is expected to be paid in 2024 and 2025.

Through September 30, 2024, the Company committed to noncancelable purchase obligations related to the procurement of materials to be used in future drug substance and drug product manufacturing under the Commercial Manufacturing Agreement. As of September 30, 2024, the total remaining contractually binding purchase obligations due to WuXi Biologics was $17.0million, which is expected to be paid in 2024 and 2025. As of September 30, 2024, $10.6million related to the procurement of materials to be used in future drug substance and drug product manufacturing was included in accounts payable and accrued expenses, which is expected to be paid in 2024 and 2025.

Unless earlier terminated, the Commercial Manufacturing Agreement remains in effect for an initial period of five years from the date of the last amendment and restatement of the agreement and thereafter automatically renews for further successive periods of five years each. Either party may terminate the agreement upon the breach or default by the other party, other than a non-payment breach, that is not timely cured after notice thereof. Both parties are also entitled to terminate the Commercial Manufacturing Agreement if the other party becomes insolvent or is the subject of a petition in bankruptcy or of any other related proceeding or event. Either party may terminate either the Commercial Manufacturing Agreement in its entirety, or an individual order, (i) to the extent the other party suffers a force majeure event that is continuing for a predefined period of time and (ii) if the other party fails to make a payment when due under the arrangement and such non-payment is not timely cured after notice thereof. Until regulatory approval and future economic benefit is probable, the Company will continue to expense costs related to batches manufactured under the Commercial Manufacturing Agreement.

Other Contracts

The Company enters into agreements with third parties in the ordinary course of business for various products and services, including those related to research, preclinical and clinical operations, manufacturing and support, supply chain, and distribution. These contracts do not contain any material minimum purchase commitments. Certain of these agreements provide for termination rights subject to the payment of termination fees and/or wind-down costs. Under such agreements, the Company is contractually obligated to make certain payments to vendors upon early termination, primarily to reimburse them for their unrecoverable outlays incurred prior to cancellation as well as any amounts owed by the Company prior to early termination. The actual amounts the Company could pay in the future to the vendors under such agreements may differ from the purchase order amounts due to cancellation provisions. The termination fees were not probable of payment as of September 30, 2024 and December 31, 2023.

Legal Proceedings

From time to time, the Company may become involved in legal proceedings or other litigation relating to claims arising in the ordinary course of business. The Company accrues a liability for such matters when it is probable that future expenditures will be made and that such expenditures can be reasonably estimated. Significant judgment is required to determine both probability and estimated exposure amount. Legal fees and other costs associated with such proceedings are expensed as incurred.

On January 31, 2023, a securities class action lawsuit captioned Brill v. Invivyd, Inc., et. al., Case No. 1:23-CV-10254-LTS, was filed against the Company and certain of its former officers in the U.S. District Court for the District of Massachusetts. The complaint alleged violations of Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5 promulgated thereunder on the basis of purportedly materially false and misleading statements and omissions concerning ADG20's effectiveness against the Omicron variant of COVID-19. The complaint sought, among other things, unspecified damages, attorneys' fees, expert fees, and other costs. The court appointed lead plaintiffs for the action on June 28, 2023. On August 23, 2023, the lead plaintiffs filed an amended complaint that made allegations similar to those in the original complaint and asserted the same claims against the same defendants as the original complaint. On October 19, 2023, the parties filed a joint stipulation to advise the court that the lead plaintiffs intended to seek leave to file a second amended complaint, and on November 22, 2023, the lead plaintiffs filed a second amended complaint that made allegations similar to those in the prior complaints and asserted the same claims against the same defendants as the prior complaints. On January 12, 2024, the defendants filed a motion to dismiss the second amended complaint in its entirety. The lead plaintiffs filed an opposition to the motion to dismiss on February 26, 2024, and the defendants filed a reply in further support of their motion to dismiss on March 27, 2024. The court heard oral arguments on the defendants' motion to dismiss on May 10, 2024. The court granted the defendants' motion to dismiss on September 18, 2024, dismissing the second amended complaint in its entirety, with prejudice and without leave to amend. The plaintiffs did not appeal the court's decision. As such, the Company has concluded that this matter is closed.

Indemnification Agreements

In the ordinary course of business, the Company may provide indemnification of varying scope and terms to its vendors, lessors, contract research organizations, contract development and manufacturing organizations ("CDMOs"), business partners and other parties

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with respect to certain matters, including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and its executive officers that require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or executive officers. The maximum potential amount of future payments that the Company could be required to make under these indemnification agreements is, in many cases, unlimited. The Company has not incurred any material costs as a result of such indemnifications and is not currently aware of any indemnification claims.

10. Common Stock

Shares Reserved for Future Issuance

As of September 30, 2024, the Company had reserved 45,909,485shares of common stock for the exercise of outstanding stock options and the issuance of awards available for grant under the Company's 2020 Equity Incentive Plan, 2021 Equity Incentive Plan and 2021 Employee Stock PurchasePlan (see Note 11).

Shelf Registration Statement

In September 2022, the Company filed a shelf registration statement on Form S-3 with the SEC (File No. 333-267643) and an accompanying base prospectus, which was declared effective by the SEC on October 5, 2022, for the offer and sale of up to $400million of the Company's securities. As of September 30, 2024, $325million of the Company's securities remained available for offer and sale under this shelf registration statement.

ATM Facility

In December 2023, the Company entered into a Controlled Equity OfferingSM Sales Agreement (the "Sales Agreement") with Cantor Fitzgerald & Co., as sales agent ("Cantor"), pursuant to which the Company may, at its option, offer and sell shares of its common stock, with a sales value of up to $75.0million, from time to time, through Cantor, acting as sales agent, in transactions deemed to be "at the market offerings", as defined in Rule 415 under the Securities Act of 1933, as amended. Cantor is entitled to a commission of 3% of the gross proceeds from any sales of such shares.

In February 2024, the Company sold 9,000,000shares of its common stock under the Sales Agreement at an average price of $4.50per share for $39.3million in net proceeds. As of September 30, 2024, $34.5million remained available for sale under the Sales Agreement.

Treasury Stock

In March 2023, the Company repurchased, and subsequently retired, 206,802shares of unvested restricted common stock at the original purchase price upon a termination of service of an employee during the vesting period. The fair value of the repurchased common stock was insignificant. Upon retirement, the shares were redesignated as authorized but unissued shares of the Company's common stock.

In May 2023, the Company repurchased 46,600shares of unvested restricted common stock at the original purchase price upon a termination of service of an employee during the vesting period. The shares of common stock repurchased were recorded as treasury stock. The fair value of the repurchased common stock was insignificant. In June 2023, the Company retired the 46,600shares of treasury stock. Upon retirement, the shares were redesignated as authorized but unissued shares of the Company's common stock.

In October 2023, the Company repurchased 31,765shares of unvested restricted common stock at the original purchase price upon a termination of service of an employee during the vesting period. The shares of common stock repurchased were recorded as treasury stock. The fair value of the repurchased common stock was insignificant. In December 2023, the Company retired the 31,765shares of treasury stock. Upon retirement, the shares were redesignated as authorized but unissued shares of the Company's common stock.

11. Stock-Based Compensation

2020 Equity Incentive Plan

The Company's 2020 Equity Incentive Plan (the "2020 Plan") provides for the Company to grant incentive stock options, non-qualified stock options, restricted stock awards, restricted stock units and other stock-based awards to employees, members of the board of directors and consultants. The 2020 Plan is administered by the board of directors or, at the discretion of the board of directors, by a committee of the board of directors. The board of directors may also delegate to one or more officers of the Company the power to grant awards to employees and certain officers of the Company. The exercise prices, vesting and other restrictions are determined at the discretion of the board of directors, or its committee or any such officer if so delegated.

The exercise price for stock options granted may not be less than the fair market value of the Company's common stock on the date of grant, as determined by the board of directors, or at least 110% of the fair market value of the Company's common stock on the date of grant in the case of an incentive stock option granted to an employee who owns stock representing more than 10% of the voting power of all classes of stock as determined by the board of directors as of the date of grant. Prior to the IPO, the Company's board of directors determined the fair value of the Company's common stock, taking into consideration its most recently available valuation of

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common stock performed by third parties as well as additional factors which may have changed since the date of the most recent contemporaneous valuation through the date of grant. Stock options granted under the 2020 Plan expire after ten yearsand typically vest over a four-year period with the first 25% vesting upon the first anniversary of a specified vesting commencement date and the remainder vesting in 36equal monthly installments over the succeeding three years, contingent on the recipient's continued employment or service. Certain awards of stock options permit the holders to exercise the option in whole or in part prior to the full vesting of the option in exchange for unvested shares of restricted common stock with respect to any unvested portion of the option so exercised.

As of September 30, 2024,there were 2,985,456shares authorized to be issued upon the exercise of outstanding stock option grants and noshares reserved for future issuance under the 2020 Plan.

2021 Equity Incentive Plan

In July 2021, the Company's board of directors adopted, and its stockholders approved, the 2021 Equity Incentive Plan (the "2021 Plan"), which became effective immediately prior to and contingent upon the execution of the underwriting agreement related to the Company's IPO. The 2021 Plan provides for the grant of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock awards, restricted stock units and other stock-based awards. The number of shares reserved for issuance under the 2021 Plan was equal to 35,075,122, which is the sum of 11,413,572new shares; plus the number of shares (not to exceed 23,661,550shares), which represents (i) the number of shares that remained available for issuance under the 2020 Plan, at the time the 2021 Plan became effective, and (ii) any shares subject to outstanding stock options or other stock awards that were granted under the 2020 Plan that are forfeited, terminate, expire or are otherwise not issued. In addition, the number of shares of the Company's common stock reserved for issuance under the 2021 Plan will automatically increase on the first day of each calendar year pursuant to the evergreen provision thereof, beginning on January 1, 2022 and continuing through January 1, 2031, in an amount equal to 5% of the shares of common stock outstanding on the last day of the calendar month before the date of each automatic increase, or a lesser number of shares determined by the board of directors. On January 1, 2022, 5,539,145shares of common stock were automatically added to the shares authorized for issuance under the 2021 Plan pursuant to the evergreen provision thereof. The number of shares to be issued under the 2021 Plan did not increase on January 1, 2023 as determined by the Company's board of directors. On January 1, 2024, 3,304,820shares of common stock were added to the shares authorized for issuance under the 2021 Plan, pursuant to the evergreen provision thereof, as determined by the Company's board of directors. The shares of common stock underlying any awards that are forfeited, cancelled, held back upon exercise or settlement of an award to satisfy the exercise price or tax withholding, repurchased or are otherwise terminated by the Company under the 2021 Plan will be added back to the shares of common stock available for issuance under the 2021 Plan.

As of September 30, 2024, there were an aggregate of 45,004,758shares authorized to be issued under the 2020 Plan and the 2021 Plan, which included 2,985,456and 18,890,298shares authorized to be issued upon the exercise of outstanding stock option grants from the 2020 Plan and 2021 Plan, respectively, and 0and 23,129,004 shares reserved for future issuance under the 2020 Plan and 2021 Plan, respectively.

Stock Option Valuation

The fair value of stock option grants is estimated using the Black-Scholes option-pricing model. Prior to its IPO in August 2021, the Company had been a private company. Due to the proximity to the IPO, the Company continues to lack sufficient company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. For options with service-based vesting conditions, the expected term of the Company's stock options has been determined utilizing the "simplified" method. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.

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Stock Option Activity

The weighted-average grant date fair value of stock options granted during the three and nine months ended September 30, 2024was $0.74and $2.06, respectively, per share. The weighted-average grant date fair value of stock options granted during the three and nine months ended September 30, 2023was $1.06and $1.15, respectively, per share.

The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the fair market value of the common stock for the options that had exercise prices lower than the estimated fair value of the Company's common stock at September 30, 2024 and 2023.

The total intrinsic value of stock options exercised was $0.1million and $0.3million for the three and nine months ended September 30, 2024, respectively. The total intrinsic value of stock options exercised was $0.1million and $0.5million for the three and nine months ended September 30, 2023, respectively.

Stock-Based Compensation Expense

As of September 30, 2024, total unrecognized stock-based compensation expense related to unvested stock-based awards was $21.5million, which is expected to be recognized over a weighted-average period of 2.3years.

2021 Employee Stock Purchase Plan

In July 2021, the Company's board of directors adopted, and its stockholders approved, the 2021 Employee Stock Purchase Plan (the "2021 ESPP"), which became effective immediately prior to and contingent upon the execution of the underwriting agreement related to the Company's IPO. A total of 1,342,773shares of common stock were initially reserved for issuance under the 2021 ESPP. There were 438,046shares issued under the 2021 ESPP as of September 30, 2024. The number of shares of common stock that may be issued under the 2021 ESPP will automatically increase on the first day of each calendar year, pursuant to the evergreen provision thereof, beginning on January 1, 2022 and continuing through January 1, 2031, by an amount equal to the lesser of (i) 1% of the shares of common stock outstanding on the last day of the calendar month before the date of each automatic increase, (ii) 2,685,546shares and (iii) an amount determined by the Company's board of directors. The number of shares to be issued under the 2021 ESPP did not increase on January 1, 2024 or January 1, 2023, pursuant to the evergreen provision thereof, as determined by the Company's board of directors. The first offering under the 2021 ESPP was June 6, 2022. As of September 30, 2024, 904,727shares remained available for issuance under the 2021 ESPP. During both the three and nine months ended September 30, 2024, the Company recognized less than $0.1million

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in related stock-based compensation expense. During both the three and nine months ended September 30, 2023, the Company recognized less than $0.1million in related stock-based compensation expense.

Warrant Expense

In November 2022, the Company entered into the PHP MSA, the PHP Work Order and a warrant agreement with respect to the PHP Warrant. To compensate for the services and deliverables provided by PHP, the Company issued 6,824,712equity-classified warrants to PHP. Each warrant shall give the right to acquire common stock of the Company at a purchase price of $3.48per share. Per the agreement, the PHP Warrant is exercisable upon either the achievement of corresponding market capitalization targets or a consummation of a fundamental transaction (as defined in the PHP Warrant); as such, there are no other requirements, including any continuous service requirements, in order for PHP to be entitled to the PHP Warrant, if and when any portion of it vests.

The aggregate grant date fair value of the PHP Warrant was $17.4million, which was recognized as warrant expense on the grant date in November 2022.

There were nowarrants issued during the three and nine months ended September 30, 2024 and 2023. As of September 30, 2024, there were 6,824,712warrants outstanding and not yet vested at a weighted-average exercise price of $3.48, with a weighted-average remaining contractual term of 8.13years.

12. Income Taxes

For the three and nine months ended September 30, 2024 and 2023, the Company recorded noincome tax benefits for the net operating losses incurred or for the research and development tax credits generated in each period, due to its uncertainty of realizing a benefit from those items. Substantially all of the Company's operating losses since inception have been generated in the U.S.

13. Defined Contribution Plan

The Company maintains a 401(k) Plan (the "401(k) Plan") for the benefit of eligible employees. The 401(k) Plan is a defined contribution plan under Section 401(k) of the Internal Revenue Code of 1986, as amended, that covers all employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. Pursuant to the terms of the 401(k) Plan, the Company is required to make non-elective contributions of 3% of eligible participants' compensation. For the three and nine months ended September 30, 2024, the Company contributed $0.2million and $0.5million, respectively, to the 401(k) Plan. For the three and nine months ended September 30, 2023, the Company contributed $0.3million and $0.6million, respectively, to the 401(k) Plan.

14. Net Loss per Share