Cabaletta Bio, Inc.

1. Basis of Presentation

Cabaletta Bio, Inc. (the Company or Cabaletta) was incorporated in April 2017 in the State of Delaware as Tycho Therapeutics, Inc. and, in August 2018, changed its name to Cabaletta Bio, Inc. The unaudited condensed consolidated financial statements include the accounts of Cabaletta Bio and its wholly owned subsidiaries: Cabaletta Bio GmbH and Cabaletta Bio (Germany) GmbH. All intercompany balances and transactions have been eliminated in consolidation.

The Company is headquartered in Philadelphia, Pennsylvania. Cabaletta is a clinical-stage biotechnology company focused on the discovery and development of engineered T cell therapies for autoimmune diseases. Principal operations commenced in April 2018.

Risks and Uncertainties

The Company does not expect to generate revenue from sales of engineered T cell therapies for autoimmune diseases or any other revenue unless and until the Company completes preclinical and clinical development and obtains regulatory approval for one or more product candidates. If the Company seeks to obtain regulatory approval for any of its product candidates, the Company expects to incur significant commercialization expenses.

The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. As a result, the Company is unable to predict the timing or amount of increased expenses or when or if the Company will be able to achieve or maintain profitability. Further, the Company is dependent on third parties for certain research and development activities, including manufacturing services (Note 5 and Note 6). Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization. Even if the Company is able to generate revenues from the sale of its product candidates, if approved, it may not become profitable. If the Company fails to become profitable or is unable to sustain profitability on a continuing basis, then it may be unable to continue its operations at planned levels and be forced to reduce its operations.

Liquidity and Going Concern

In accordance with Accounting Standards Codification (“ASC”) 205-40, Going Concern, ("ASC 205-40") the Company evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern. The Company has sustained annual operating losses since inception and expects to continue to generate operating losses for the foreseeable future. As of March 31, 2025, the Company has incurred an accumulated deficit of$385,044 and has a cash and cash equivalents balance of$131,830. The Company’s ultimate success depends on the outcome of its research and development activities. Management expects to incur additional losses in the future as it continues its research and development and will need to raise additional capital to fully implement its business plan and to fund its operations. The Company intends to raise such additional capital through a combination of equity offerings, debt financings, government funding arrangements, strategic alliances or other sources. However, if such financing is not available at adequate levels and on a timely basis, or such agreements are not available on favorable terms, or at all, as and when needed, the Company will need to reevaluate its operating plan and may be required to delay or discontinue the development of one or more of its product candidates or operational initiatives. The Company expects that its current cash and cash equivalents may not be sufficient to fund operations for at least the next twelve months from the date of issuance of these unaudited condensed consolidated financial statements. The Company's cash forecast contains estimates and assumptions based on success of ongoing clinical trials, and management cannot predict the amount or timing of all expenditures with certainty. Accordingly, the Company has concluded that substantial doubt exists about the Company’s ability to continue as a going concern. The accompanying financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business.

2. Summary of Significant Accounting Policies

Unaudited Interim Financial Information

The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with generally accepted accounting principles (GAAP) and the applicable rules and regulations of the SEC regarding interim financial reporting. Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification and Accounting Standards Updates (ASU) of the Financial Accounting Standards Board (FASB). As permitted under these rules, certain footnotes and other financial information that are normally required by GAAP have been condensed or omitted. The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

In the opinion of management, the accompanying unaudited condensed consolidated financial statements include all normal and recurring adjustments (which consist primarily of accruals and estimates that impact the financial statements) considered necessary to present fairly the Company’s financial position as of March 31, 2025 and the results of its operations and its cash flows for the three months ended March 31, 2025 and 2024. The results for the three months ended March 31, 2025 are not necessarily indicative of results to be expected for the year ending December 31, 2025, any other interim periods, or any future year or period. The balance sheet as of December 31, 2024 included herein was derived from the audited financial statements as of that date. The unaudited condensed consolidated financial statements, presented herein, do not contain the required disclosures under GAAP for annual financial statements. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited financial statements, which are included in the Company’s 2024 Annual Report on Form 10-K, filed with the SEC on March 31, 2025 (2024 Annual Report).

Use of Estimates

The preparation of the condensed consolidated financial statements in conformity with accounting GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying consolidated financial statements include but are not limited to advance payments and accruals related to the Company’s research and development expenses. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.

Off-Balance Sheet Risk and Concentrations of Credit Risk

Financial instruments, which potentially subject the Company to significant concentrations of credit risk, consist of cash and cash equivalents, which are invested in U.S. treasury-based money market funds. A portion of the Company’s cash is maintained at two federally insured financial institutions, and account balances may at times exceed federally insured limits. The Company has not experienced any losses in such accounts and management believes that the Company is not exposed to significant credit risk. The Company has no off‑balance sheet risk, such as foreign exchange contracts, option contracts or other foreign hedging arrangements.

The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. Cash equivalents consist primarily of amounts invested in money market accounts.

Significant Accounting Policies

There have been no significant changes to the Company’s accounting policies during the three months ended March 31, 2025, as compared to the significant accounting policies described in Note 2 of the “Notes to the Financial Statements” in the Company’s audited financial statements included in its 2024 Annual Report.

Fair Value Measurement

Assets and liabilities recorded at fair value on a recurring basis in the balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. 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. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows:

Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date.

Level 2—Inputs (other than quoted prices included in Level 1) that are either directly or indirectly observable for the asset or liability. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active.

Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Recently Issued Accounting Pronouncements

In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures. ASU 2023-09 enhances the transparency about income tax information through improvements to income tax disclosures primarily related to the rate reconciliation and income taxes paid information. The guidance is effective for public business entities for annual periods beginning after December 15, 2024. Early adoption is permitted. This update is effective beginning with the Company’s 2025 fiscal year annual reporting period. The Company is currently planning to adopt this guidance when effective and is assessing the impact of the adoption on the Company’s consolidated financial statements and accompanying footnotes.

In November 2024, the FASB issued ASU 2024-03, Income Statement (Subtopic 220-40): Reporting Comprehensive Income-Expense Disaggregation Disclosures. ASU 2024-03 requires enhanced disclosures about components of expense captions on the face of the income statement. This standard will be effective for fiscal years beginning after December 15, 2026. Early adoption is permitted. ASU 2024-03 applies on a prospective basis for periods beginning after the effective date. However, retrospective application to any or all prior periods presented is permitted. The Company is currently planning to adopt this guidance when effective and is assessing the impact of the adoption on the Company’s consolidated financial statements and accompanying footnotes.

3. Fair Value Measurements

Fair value of financial instruments

At March 31, 2025 and December 31, 2024, the Company’s financial instruments included cash and cash equivalents, accounts payable and accrued expenses. The carrying amounts for cash and cash equivalents, accounts payable and accrued expenses reported in the Company’s consolidated financial statements for these instruments approximate their respective fair values because of the short-term nature of these instruments.

The following tables present information about the Company’s financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values:

Money market funds are measured at fair value on a recurring basis using quoted prices and are classified as Level 1 inputs.

4. Accrued and Other Current Liabilities

Accrued and other current liabilities consist of the following:

5. Collaborations, Licensing Agreements and Other Agreements

Amended and Restated License Agreement with the Trustees of the University of Pennsylvania and Children’s Hospital of Philadelphia

In August 2018, the Company entered into a license agreement with Penn, as amended and restated in July 2019 to include the Children’s Hospital of Philadelphia (CHOP) as a party, and as amended in May 2020 and October 2021 (the License Agreement) pursuant to which the Company obtained (a) a non-exclusive, non-sublicensable worldwide license to certain of Penn’s intellectual property to conduct research, product development, clinical trials, cell manufacturing and other activities, and (b) an exclusive, worldwide, royalty-bearing right and license, with a right to sublicense, on a target-by-target basis, under certain of Penn’s intellectual property to make, use, sell, offer for sale, import, and otherwise commercialize products for the treatment of autoimmune and alloimmune diseases. Unless earlier terminated, the License Agreement expires on the expiration or abandonment or other termination of the last valid claim in Penn’s intellectual property licensed by the Company. The Company may terminate the License Agreement at any time for convenience upon 60 days' written notice. In the event of an uncured, material breach, Penn may terminate the License Agreement upon 60 days' written notice. Under the terms of the License Agreement, the Company was obligated to pay $2,000 annually forthree years beginning August 2018 for funding to the laboratories of each of Drs. Milone and Payne. This was satisfied through completed sponsored research agreements with a total cost of $12,560. During the term of the License Agreement until the first commercial sale of the first product, the Company is obligated to pay Penn a non-refundable, non-creditable annual license maintenance fee of $10. In May 2020, the Company paid Penn an additional, non-refundable, non-creditable license fee of $33 under the amended License Agreement.

The Company is required to pay certain milestone payments upon the achievement of specified clinical and commercial milestones. Milestone payments are reduced by a certain percentage for the second product that achieves a milestone, by an additional percentage for the third product that achieves a milestone, and so on, for each subsequent product that achieves a milestone. In the event that the Company is able to successfully develop and launch multiple products under the License Agreement, total milestone payments could be approximately $21,000. Penn is also eligible to receive tiered royalties at percentage rates in the low single-digits, subject to an annual minimum royalty, on annual worldwide net sales of any products that are commercialized by the Company or its sublicensees that contain or incorporate, or are covered by, the intellectual property licensed by the Company. To the extent the Company sublicenses its license rights under the License Agreement, Penn would be eligible to receive tiered sublicense income at percentage rates in the mid-single to low double-digits. There wereno amounts due under the License Agreement as of March 31, 2025.

Master Translational Research Services Agreements

In October 2018 and February 2023, the Company entered into services agreements (the CAART and CARTA Services Agreements) with Penn for research, development and manufacturing services from various laboratories within Penn. The activities are detailed in separately executed Penn organization-specific addenda. In May 2020, the Company amended its Addendum with the Center for Advanced Retinal and Ocular Therapeutics (CAROT) to expand access to vector manufacturing.

Research and development expense related to executed addenda under the master translational research service agreements with Penn recognized in the accompanying statements of operations was $1,042 and $713 for the three months ended March 31, 2025 and 2024, respectively. The Company is committed to pay up to a remaining $2,250 under the CARTA Services Agreement for cell processing manufacturing through December 31, 2025. The Company may incur additional expenses up to$643 through the remaining term of the CAROT Amended Addendum.

Exclusive License Agreement with IASO Biotherapeutics

On October 7, 2022, the Company entered into an Exclusive License Agreement (the IASO Agreement) with Nanjing IASO Biotherapeutics Co., Ltd. (IASO). Pursuant to the IASO Agreement, the Company received an exclusive, worldwide license under certain IASO intellectual property to use a novel clinical-stage anti-CD19 binder to develop, manufacture, commercialize and otherwise exploit T cell products directed to CD19 for the purpose of diagnosis, prevention or treatment of any autoimmune or alloimmune indications in humans. As partial consideration for the exclusive license, IASO received an upfront payment of $2,500. IASO is also eligible to receive up to mid double digit millions in milestone payments based upon the achievement of specified pre-clinical, development and regulatory milestones, and up to an additional low triple digit millions in milestone payments based upon achievement of specified sales milestones, for a total consideration, inclusive of the upfront payment, of up to $162,000, along with tiered mid-single digit royalties on future net sales for licensed products that may result from the IASO Agreement. Upon the U.S. Food and Drug Association’s clearance of the rese-cel Investigational New Drug application for the treatment of systemic lupus erythematosus in March 2023, a milestone payment of $1,000 was recognized in the accompanying statements of operations. A milestone payment of $1,500 was paid to IASO in the first quarter of 2024 after the first patient in a rese-cel trial was dosed.

IASO has the right of first negotiation if the Company desires to grant a third party an exclusive license to develop, manufacture, commercialize or otherwise exploit the licensed products in the Greater China region. Pursuant to the IASO Agreement, each of IASO and the Company have agreed, subject to certain exceptions, to refrain from engaging in certain competitive activities with respect to certain programs. The Company also may sublicense through multiple tiers the rights granted to it by IASO under the IASO Agreement at any time, however, it must pay IASO a low double-digit percentage of any revenue obtained from sublicenses or options to third parties, subject to certain customary exclusions. The IASO Agreement will continue on a country-by-country, licensed product-by-licensed product basis until the expiration of the royalty term as identified in the IASO Agreement, unless earlier terminated. Each of the Company and IASO may terminate the Agreement for a material, uncured breach or insolvency of the other party. The Company may also terminate the Agreement at will upon advance written notice and in the event IASO rejects the Agreement due to bankruptcy-related matters. IASO may also terminate the Agreement if the Company fails to achieve certain specified diligence milestones in a timely manner and/or if the Company commences any patent challenges with respect to the patents and patent applications relating to the licensed sequence, in each case upon advance written notice.

Licence and Supply Agreement with Oxford Biomedica

In December 2021, the Company entered into a Licence and Supply agreement (LSA) with Oxford Biomedica (UK) Limited (Oxford), wherein the LSA grants the Company a non-exclusive license to Oxford’s LentiVector® platform for its application in the Company’s DSG3-CAART program and put in place a multi-year vector supply agreement. Oxford is eligible to receive regulatory and sales milestones in the low tens of millions and royalties in the low single digits on net sales of products that incorporate the Oxford technology. In May 2023, the Company amended the LSA with Oxford to expand the license to include the Company's rese-cel program for an upfront fee of $500. In August 2023, the Company and Oxford entered into a vector supply agreement for rese-cel, and a related second amendment to the LSA, with a total cost under the vector supply agreement of up to approximately $5,000, which has been fully expensed as of December 31, 2024. In February 2024, the Company and Oxford entered into a third amendment to the LSA to update the patent schedule. In June 2024, the Company and Oxford entered into a fourth amendment to the LSA elimin ating royalties on net sales of products that incorporate the Oxford technology if Oxford manufactures the vector. In December 2024 and March 2025, the Company and Oxford entered into work orders with a cost of approximately $11,000 for certain process characterization activities as part of commercial readiness activities. The Company can terminate the LSA or any work order under the LSA at will upon advance written notice and subject to certain cancellation fees.

Option and License Agreement with Autolus

In January 2023, the Company entered into an Option and License Agreement (Autolus Agreement) with Autolus Holdings (UK) Limited (Autolus), wherein the Autolus Agreement granted the Company a non-exclusive license to access Autolus' RQR8 technology in its CD19-CAR T cell therapy program, and subject to additional nominal option exercise fees, up to four additional targets. In January 2025, the Company and Autolus agreed to novate the Autolus Agreement with both Autolus and Autolus Limited jointly assuming the rights, obligations and liabilities of Autolus, under the Autolus Agreement. Under the terms of the Autolus Agreement, the Company was required to pay Autolus an upfront license fee of $1,200 that was recognized as expense in the first quarter of 2023 in the accompanying statements of operations, of which $1,100 was paid in 2023 and $100 was paid in January 2024. Autolus is also eligible to receive regulatory milestones of up to $12,000 for each licensed target, sales milestones of up to a total of $15,000 and royalties in the low single digits on net sales of all products that incorporate the RQR8 technology. The Autolus Agreement will continue on a country-by-country, licensed product-by-licensed product basis until the expiration of the royalty term as identified in the Autolus Agreement, unless earlier terminated. The Company can terminate the Autolus Agreement at will upon advance written notice. Each of the Company and Autolus may terminate the Agreement for a material, uncured breach or insolvency of the other party.

6. Commitments and Contingencies

Manufacturing Agreements

In January 2021, the Company entered into a Development and Manufacturing Services Agreement (Minaris Advanced Therapies Agreement) with Minaris Advanced Therapies TM, LLC, or Minaris Advanced Therapies (f/k/a WuXi Advanced Therapies, Inc.) to serve as an additional cell processing manufacturing partner for the MuSK-CAART Phase 1 clinical trial, or MusCAARTes TM trial. The Minaris Advanced Therapies Agreement is scheduled to expire upon completion of Minaris Advanced Therapies' services related to MuSK-CAART and rese-cel. In August 2023, and as extended in August 2024, the Company entered into an agreement with Minaris Advanced Therapies to serve as one of the Company's manufacturing partners for the global clinical development of rese-cel in multiple indications, including potential late-stage clinical trials and commercial readiness activities for rese-cel. Under the August 2023 work orders, Minaris Advanced Therapies converted the Company’s non-dedicated suite to a dedicated suite for GMP manufacturing for the Company’s rese-cel and MuSK-CAART programs, or the Dedicated Suite, for an initial term of 18 months with two 18-month extensions at the Company’s sole option on six months' notice prior to the end of the term. In August 2024, the Company sent a notice to Minaris Advanced Therapies to extend the initial term of the Minaris Advanced Therapies Agreement by 18 months through August 2026. In addition, the Company agreed to certain monthly minimum runs. In August 2024, the 2023 work order related to GMP manufacturing was amended to reduce the minimum monthly runs through the end of 2024. In lieu of the original $1,500 termination fee under the terms of the Minaris Advanced Therapies Agreement, the Company would incur up to a $1,080 termination fee if it terminates both the rese-cel and MuSK-CAART work orders for any reason. The Company may terminate for convenience the Minaris Advanced Therapies Agreement or any work order with six months' prior written notice. However, the Company may not terminate the Dedicated Suite without terminating both the MuSK-CAART and rese-cel GMP run work orders. Minaris Advanced Therapies may terminate for convenience the Minaris Advanced Therapies Agreement or any work order on 18 months' prior written notice, but such notice may not be effective prior to February 2028.

In December 2024, the Company entered into a Development and Manufacturing Services Agreement (the Lonza Agreement) with Lonza Houston Inc. (Lonza) to serve as one of the Company's manufacturing partners for the global clinical development of rese-cel in multiple indications, including potential late-stage clinical trials and preparations for commercial readiness. Under the initial work order, Lonza will perform cell therapy manufacturing activities for Cabaletta’s CAR-T cell therapy product rese-cel for a term of 12 months with the ability to extend the manufacturing period subject to the terms of the Lonza Agreement.

Other Purchase Commitments

In the normal course of business, the Company enters into various purchase commitments with third-party contract manufacturers for the manufacture and processing of its product candidates and related raw materials, contracts with contract research organizations for clinical trials and agreements with vendors for other services and products for operating purposes. These agreements generally provide for termination or cancellation, other than for costs already incurred.

Indemnification

The Company enters into certain types of contracts that contingently require the Company to indemnify various parties against claims from third parties. These contracts primarily relate to (i) the Company’s Amended and Restated Bylaws, as amended, (bylaws) under which the Company must indemnify directors and executive officers, and may indemnify other officers and employees, for liabilities arising out of their relationship, (ii) contracts under which the Company must indemnify directors and certain officers and consultants for liabilities arising out of their relationship, (iii) contracts under which the Company may be required to indemnify partners against certain claims, including claims from third parties asserting, among other things, infringement of their intellectual property rights, and (iv) procurement, consulting, or license agreements under which the Company may be required to indemnify vendors, consultants or licensors for certain claims, including claims that may be brought against them arising from the Company’s acts or omissions with respect to the supplied products, technology or services. From time to time, the Company may receive indemnification claims under these contracts in the normal course of business. In addition, under these contracts, the Company may have to modify the accused infringing intellectual property and/or refund amounts received.

In the event that one or more of these matters were to result in a claim against the Company, an adverse outcome, including a judgment or settlement, may have a material adverse effect on the Company’s future business, operating results or financial condition.

It is not possible to determine the maximum potential amount under these contracts due to the limited history of prior indemnification claims and the unique facts and circumstances involved in each particular agreement.

Litigation

From time to time, the Company may become involved in litigation or legal proceedings. While the outcome of any such proceedings cannot be predicted with certainty, as of March 31, 2025, the Company is not involved in any material litigation or legal proceedings that it would expect to have a material adverse impact on its financial position, results of operations, or cash flows.

7. Segment Information

Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the Chief Operating Decision Maker (CODM) in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s CODM is the Chief Executive Officer (CEO). The Company has determined it operates in a single operating segment and has one reportable segment. The segment consists of the development of clinical and preclinical product candidates for the discovery and development of innovative engineered T cell therapies and related administrative activities. The CODM assesses performance and allocates resources based on the Company’s consolidated statement of operations, which is reported on the income statement as consolidated net loss and considers forecast-to-actuals variances on a quarterly basis for expenses that are deemed significant. Further, the CODM reviews the segment’s assets based on the consolidated balance sheet to assess liquidity and funding capacity. The majority of the Company's assets are located in the United States.

The Company’s CODM views specific categories within expenses as significant given the direct correlation between cash burn and profitability as a pre-revenue company. Significant segment expenses, as provided to the CODM, are presented below. For additional information on the year over year change of segment expenses refer to Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

(1)Other research and development costs includes costs associated with information technology, travel, medical and scientific symposiums and conferences.

8. Leases

At the inception of an arrangement, the Company determines whether the arrangement is or contains a lease and assesses its classification based on the unique facts and circumstances present in the arrangement. The Company leases office and laboratory space and has two manufacturing agreements that have been determined to include embedded leases.

Operating lease commitments

The Company leases office and laboratory space which include rent escalations and are subject to additional variable charges, including common area maintenance, property taxes and property insurance. Given the variable nature of such costs, they are recognized as expense as incurred. Additionally, some of the Company’s leases are subject to certain fixed fees which the Company has determined to be non-lease components. The Company has elected the practical expedient to account for lease and non-lease components as a single-lease component and has included fixed payments related to non-lease components in calculating the operating lease liability.

Finance lease commitments - Embedded leases

As described further in Note 6, in August 2023, the Company entered into new work orders under the Minaris Advanced Therapies Agreement for Minaris Advanced Therapies to serve as one of the Company’s cell processing manufacturing partners for the global clinical development of rese-cel. Minaris Advanced Therapies converted the Company’s non-dedicated suite to a Dedicated Suite for GMP manufacturing for the Company’s rese-cel and MuSK-CAART programs, for an initial term of 18 months. The terms of the August 2023 work orders included both fixed costs and contingent variable costs. The lease commenced October 1, 2023. In 2024, the Company remeasured the lease following the resolution of the contingency related to variable costs and an amendment to the 2023 work order, which extended the term of the agreement by an additional 18 months through August 2026. The Company may terminate the Dedicated Suite lease for convenience with six months’ prior written notice and up to a $1,080 termination fee if both the rese-cel and MuSK-CAART work orders are terminated.

As described further in Note 6, in December 2024, the Company entered into the Lonza Agreement with Lonza to serve as one of the Company's cell processing manufacturing partners. Under the initial work order, Lonza will perform cell therapy manufacturing activities for the CAR-T cell therapy product rese-cel for a term of 15 months with the ability to extend the manufacturing period subject to the terms of the Lonza Agreement. The Lonza Agreement was evaluated under ASC 842 and determined to contain an embedded finance lease commencing in March 2025, resulting in the recognition of a right-of-use asset and lease liability of $14,930.

Summary of leases under ASC 842

The following table contains information pertaining to the Company’s operating and finance leases for the three months ended March 31, 2025 and 2024.

For finance leases embedded in CDMO arrangements, interest expense is recognized using the effective interest method, applying the Company's incremental borrowing rate as required by ASC 842, and amortization expense is recognized on a straight-line basis over the shorter of the life of the asset or the term of the lease.

Future lease payments under the non-cancelable leases as of March 31, 2025 are as follows:

9. Common Stock

Common Stock

Pursuant to the Company’s Third Amended and Restated Certificate of Incorporation filed in October 2019, the Company is authorized to issue 143,590,481 shares of voting common stock and 6,409,519 sharesof non-voting common stock. Holders of voting common stock shall have the exclusive right to vote for the election of directors of the Company and on all other matters requiring stockholder action. Each share of the Company’s non-voting common stock may be converted at any time into one share of common stock at the option of its holder by providing 61 days written notice to the Company, subject to certain limitations, as described in the amended and restated certificate of incorporation. In May 2024,1,444,295 shares of non-voting common stock was converted to voting common stock and no shares of non-voting common stock remain outstanding as of March 31, 2025.

At-the-Market Offering

On March 31, 2025, the Company converted the S-3ASR to an S-3 (File No. 333-278126) by post-effective amendments. This S-3 was declared effective on March 31, 2025. The Company has a Sales Agreement with TD Securities (USA) LLC (as successor to Cowen and Company, LLC) (TD Cowen) to provide for the offering, issuance and sale of up to an aggregate amount of $200.0 million of common stock from time to time in “at-the-market” offerings (2024 ATM Program) pursuant to its S-3, and subject to the limitations thereof. In December 2024, the Company sold 1,225,000 shares pursuant to the 2024 ATM Program for net proceeds of $5,129, after deducting commissions of $105.

The Company previously had a Sales Agreement with TD Cowen to provide for the offering, issuance and sale of up to an aggregate amount of $100.0 million of common stock from time to time in “at-the-market” offerings (2023 ATM Program) pursuant to its shelf registration statement on Form S-3 (File No. 333-270599), which was declared effective April 26, 2023. During the year ended December 31, 2023, the Company sold 4,760,899 shares pursuant to the 2023 ATM Program for net proceeds of $91,740, after deducting commissions of $2,352. In the first quarter of 2024, the Company sold 258,070 additional shares, completing the 2023 ATM Program for net proceeds of $5,746, after deducting commissions of $147.

2018 Stock Option and Grant Plan

In September 2018, the Company adopted the 2018 Stock Option and Grant Plan (the 2018 Plan), which provided for the Company to sell or issue common stock, or other stock-based awards, to employees, members of the board of directors and consultants of the Company. The Company generally granted stock-based awards with service conditions only (service-based awards), although there was one grant with performance conditions. As of December 31, 2020, there wereno unvested options with performance conditions. Stock options granted under the 2018 Plan generally vest over three tofour years. A total of 1,959,411 options were granted under the 2018 Plan prior to the Company’s IPO in October 2019. No further grants may be made under the 2018 Plan subsequent to the IPO.

2019 Stock Option and Incentive Plan

The 2019 Stock Option and Incentive Plan (2019 Plan) was approved by the Company’s board of directors on October 14, 2019, and became effective on October 23, 2019. The 2019 Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock units, restricted stock awards, unrestricted stock awards, cash-based awards and dividend equivalent rights to the Company’s officers, employees, directors and consultants. The number of shares initially reserved for issuance under the 2019 Plan was 2,342,288, which will be increased each January 1 thereafter by 4% of the number of shares of the Company’s common stock outstanding on the immediately preceding December 31 or such lesser number of shares determined by the Company’s board of directors or compensation committee of the board of directors. On June 1, 2023, at the 2023 Annual Meeting of Stockholders of the Company, the stockholders of the Company approved Amendment No. 1 to the 2019 Plan, increasing the number of shares of common stock reserved for issuance under the 2019 Plan by 3,000,000 shares. On January 1, 2025, the total number of shares under the 2019 Plan was increased by 2,029,724; shares pursuant to the 2019 Plan Evergreen Provision. As of March 31, 2025, there were 573,972 shares remaining available for issuance under the 2019 Plan.

A summary of stock option activity is presented below:

The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the Company’s common stock. The weighted average grant-date fair value of stock options granted during the three months ended March 31, 2025 and 2024 was $1.45 and $19.72, respectively.

The fair value of each award is estimated using Black-Scholes based on the following assumptions:

Black-Scholes requires the use of subjective assumptions which determine the fair value of stock-based awards. These assumptions include:

Expected term—The expected term represents the period that stock-based awards are expected to be outstanding. The expected term for option grants is determined using the simplified method, which is the midpoint between the vesting period and the contractual term of the option.

Expected volatility—Expected volatility is estimated using the Company's stock price since its IPO in October 2019 and comparable publicly traded biotechnology companies for any period prior to the IPO needed to equal the expected term of the stock-based awards. The comparable companies were chosen based on their similar size, stage in the life cycle or area of specialty. The Company will continue to apply this process until historical information regarding the volatility of its own stock price becomes available to equal the expected term of stock-based awards.

Risk-free interest rate—The risk-free interest rate is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected term of a stock-based award.

Expected dividend—The Company has never paid dividends on its common stock and has no plans to pay dividends on its common stock. Therefore, the Company used an expected dividend yield of zero.

Stock-based Compensation

The Company has recorded stock-based compensation in the accompanying statements of operations as follows:

As of March 31, 2025, there was $49,872 of unrecognized compensation cost related to unvested option awards, which is expected to be recognized over a weighted-average period of 2.7 years.

2019 Employee Stock Purchase Plan

The 2019 Employee Stock Purchase Plan (2019 ESPP) was approved by the Company’s board of directors on October 14, 2019, and became effective on October 23, 2019. A total of 234,229 shares of common stock were initially reserved for issuance under the 2019 ESPP, and such number of shares will be increased each January 1 thereafter through January 1, 2029 by the least of (i)234,229 shares of common stock, (ii)1% of the number of shares of the Company’s common stock outstanding on the immediately preceding December 31 or (iii) such lesser number of shares determined by the 2019 ESPP’s administrator. There wasno increase to the total number of shares available under the 2019 ESPP on January 1, 2024, 2023 or 2022, respectively. As of March 31, 2025, there were 314,259 shares remaining available for issuance under the 2019 ESPP.

Employee contributions are made through payroll deductions of up to 15% of eligible compensation over the offering period. A participant may not accrue rights to purchase more than $25 worth of the Company’s common stock for each calendar year in which such right is outstanding. At the end of each offering period, shares of the Company’s common stock may be purchased at 85% of the lesser of the Company’s common stock on (i) the first trading day of the relevant offering period and (ii) the last trading day of the relevant offering period. Each offering period will be six months in duration and will commence on each December 1 and June 1.

10. Income Taxes

The Company didnot record an income tax benefit in its statements of operations for the three months ended March 31, 2025 and 2024 as it is more likely than not that the Company will not recognize the federal and state deferred tax benefits generated by its losses. The Company has provided a valuation allowance for the full amount of its net deferred tax assets and liabilities as of March 31, 2025 and December 31, 2024, as management has determined it is more likely than not that any future benefit from deductible temporary differences and net operating loss and tax credit carryforwards would not be realized. The Company hasnot recorded any amounts for unrecognized tax benefits as of March 31, 2025 and December 31, 2024.

11. Net Loss Per Share

The Company calculates basic and diluted net loss per share in conformity with the two-class method required for participating securities. In May 2024, the remaining 1,444,295 shares of non-voting common stock were converted to voting common stock and no shares of non-voting common stock remain outstanding. Since the rights of the voting and non-voting common stock are identical, except with respect to voting, the undistributed losses of the Company have been allocated on a proportionate basis to the two classes. Basic net loss per share of common stock is computed by dividing the net loss per share of common stock by the weighted average number of shares of common stock outstanding for the period.

The weighted average shares of common stock outstanding as of March 31, 2024 included outstanding pre-funded warrants to purchase up to an aggregate of 1,168,054 shares of common stock. No pre-funded warrants remain outstanding as of March 31, 2025. Diluted net loss per share is calculated using the if-converted method as of March 31, 2024, which assumes conversion of all non-voting common stock to voting common stock.

The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share, as their effect is anti-dilutive: