CytomX Therapeutics, Inc.

1. Description of the Business

CytomX Therapeutics, Inc. (the “Company”) is a clinical-stage, oncology-focused biopharmaceutical company developing potent biologics designed to remain masked and inactive in healthy tissue and to be unmasked and preferentially activated in the tumor microenvironment. The Company aims to build a commercial enterprise to maximize its impact on the treatment of cancer. The Company is advancing potential first-in-class and best-in-class therapeutics created using its PROBODY therapeutic technology platform that could meaningfully improve outcomes for cancer patients. Its proprietary and unique PROBODY technology platform is designed to enable “conditional activation” of masked drug candidates in the tumor microenvironment across multiple therapeutic modalities. The Company is located in South San Francisco, California and was incorporated in the state of Delaware in September 2010.

2. Basis of Presentation and Summary of Significant Accounting Policies

Basis of Presentation

The accompanying interim condensed financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting.

Unaudited Interim Financial Information

The accompanying interim condensed financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the results of operations for the periods presented.

The condensed results of operations for this interim period are not necessarily indicative of the results to be expected for the full year or for any other future year or interim period. The accompanying condensed financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 filed with the SEC.

Use of Estimates

The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates.

Leases

The Company determines if an arrangement is or contains a lease at inception. Operating leases are recorded as operating lease right-of-use (“ROU”) assets and operating lease liabilities in the Company’s balance sheet. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company uses an implicit rate when readily available, or its incremental borrowing rate based on the information available at lease commencement date in determining the present value of lease payments. The operating lease ROU assets also include any lease prepayments made and reduced by lease incentives. The Company’s lease terms may include options to extend the lease when it is reasonably certain that such option will be exercised. Lease expenses are recognized on a straight-line basis over the lease term. The Company elected the short-term lease recognition exemption. The Company’s operating lease arrangements include lease and non-lease components which are generally accounted for separately.

Significant Accounting Policies

There have been no material changes to our significant accounting policies this interim period as compared to the significant accounting policies disclosed in “Note 2. Basis of Presentation and Summary of Significant Accounting Policies” of the “Notes to Financial Statements” included in Part II, Item 8 of our 2025 Annual Report on Form 10-K for the year ended December 31, 2025 filed with the SEC.

Recently Issued Accounting Standards Not Yet Adopted

In November 2024, the FASB issued Accounting Standards Update (“ASU”) 2024-03, Disaggregation of Income Statement Expenses (“ASU 2024-03”), which enhances transparency in income statement disclosures. ASU 2024-03 requires entities to disclose detailed information about specific components of income statement expenses, such as employee compensation, depreciation, and amortization, as well as other significant expense categories. The objective is to provide financial statement users with greater insight into the nature and variability of expenses, improving their ability to analyze financial performance and make informed decisions. ASU 2024-03 is effective for the annual reporting periods beginning after December 15, 2026 and for interim periods within annual reporting periods beginning after December 15, 2027 with early adoption permitted. The Company expects to adopt this ASU during the year ended December 31, 2027 on a prospective basis and is currently evaluating the impact on its financial statements.

3. Net Income (Loss) Per Share

Basic net income (loss) per share is calculated by dividing the net income (loss) attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period. Diluted net income (loss) per share is calculated by using the weighted-average number of shares of common stock outstanding, plus potential dilutive common stock during the period. Diluted net loss per share is the same as basic net loss per share in the period when the effect of the potentially dilutive securities is anti-dilutive. The pre-funded warrants have been included in both the basic and diluted EPS calculation.

The following table presents the calculation of basic and diluted net income per share:

The following weighted-average outstanding shares of potentially dilutive securities are excluded from the computation ofdiluted net income (loss) per share for the periods presented, because including them would have been anti-dilutive:

4. Fair Value Measurements and Investments

The Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows:

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Level I: Inputs which include quoted prices in active markets for identical assets and liabilities.

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Level II: Inputs other than Level I that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

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

The carrying amounts of the Company’s financial instruments, including restricted cash, accounts receivable, accounts payable and accrued liabilities, approximate fair value due to their relatively short maturities. The Company’s financial instruments are comprised of Level I and Level II assets, consisting primarily of highly liquid money market funds which are included in cash equivalents and restricted cash, and U.S. Treasury securities which are included in short-term investments. The Company's U.S. Treasury securities are classified as Level II marketable securities and are valued using third-party pricing sources, which can include observable market prices, interest rates and yield curves observable at commonly quoted intervals for similar assets as observable inputs for pricing.

The following tables set forth the fair value of the Company’s investments subject to fair value measurements on a recurring basis and the level of inputs used in such measurements:

As of June 30, 2026 and December 31, 2025, interest receivable of $1.5 million and $0.5 million, respectively, primarily related to short- term investments are included in prepaid expenses and other current assets.

There were 15 debt securities available-for-sale in an unrealized loss position as of June 30, 2026 and none as of December 31, 2025. During the three and six months ended June 30, 2026, the Company did not record an allowance for credit losses or other impairment charges on our marketable securities. Based upon the quarterly impairment review, the Company determined that the unrealized losses were not attributed to credit risk but were primarily associated with changes in interest rates and market liquidity. As of June 30, 2026, the contractual maturities of the Company's short-term U.S. Treasury securities were less than one year. Based on the scheduled maturities of these marketable securities, the Company determined that it is more likely than not that it will hold the securities to maturity and recover its amortized cost basis.

5. Accrued Liabilities

Accrued liabilities consisted of the following:

6. Collaboration and License Agreements

The following table summarizes the revenue by collaboration partner:

Amgen, Inc.

On September 29, 2017, the Company entered into a Collaboration and License Agreement with Amgen, Inc. (the "Amgen Agreement") pursuant to which the parties collaborated on the research, development, and commercialization of conditionally activated T-cell engager ("TCE") therapies, including CX-904, an EGFR-targeting TCE candidate. In connection with the agreement, the Company received a $40.0 million upfront payment and $20.0 million from Amgen's purchase of the Company's common stock, with CytomX responsible for certain early-stage development activities and Amgen responsible for late-stage development and commercialization of selected programs.

Following FDA clearance of the IND for CX-904 in 2022 and advancement into Phase 1 clinical development, CytomX and Amgen jointly discontinued the program in March 2025. Effective the second quarter of 2025, Amgen terminated its rights to both the EGFR program and an additional Amgen-selected target, resulting in the recognition of all remaining deferred revenue associated with these programs by June 30, 2025. As of June 30, 2025, the Company had completed its performance obligations under the Amgen Agreement.

At the initiation of the collaboration, CytomX had the option to select from programs specified in the Amgen Agreement, an existing preclinical stage TCE product from the Amgen preclinical pipeline. In March 2018, CytomX selected the programand this program, CX-908, a PROBODY T cell engager targeting CDH3 and CD3, is currently in preclinical development. CytomX is responsible, at its expense, for converting this program to a conditionally activated TCE product, and thereafter, will be responsible for development, manufacturing, and commercialization of the product (“CytomX Product”). Amgen is eligible to receive up to $203.0 million in development, regulatory, and commercial milestone payments for the CytomX Product, and tiered mid-single digit to low double-digit percentage royalties.

Astellas Pharma Inc.

On March 23, 2020, the Company entered into a Collaboration and License Agreement with Astellas Pharma Inc. ("Astellas") to research, develop, and commercialize PROBODY therapeutic candidates against up to six oncology targets, including an initial target and potential additional targets. Under the agreement, the Company received an $80.0 million upfront payment and is eligible to receive development, regulatory and commercial milestone payments, as well as tiered royalties on future product sales.

Since inception of the collaboration, the Company has achieved multiple development milestones on selected the collaboration targets, including a $5.0 million payment for the initiation of GLP toxicology studies by Astellas, which was fully recognized in the first quarter of 2025.

In the first quarter of 2026, Astellas chose not to advance the remaining preclinical programs and terminated the Astellas Agreement effective May 12, 2026, which resulted in the completion of the Company's performance obligation and recognition of the remaining deferred revenue by the second quarter of 2026. As a result, a cumulative adjustmentof $7.1 million of revenue was recognized in the first quarter of 2026, which lowered the net loss per share by $0.04 for the six months ended June 30, 2026. It has no impact on the net loss per share of the current quarter. As of June 30, 2026, there was no deferred revenue relating to the Astellas Agreement. Deferred revenue was $8.6 million as of December 31, 2025. The amount due from Astellas under the Astellas Agreement was$30 thousand as of June 30, 2026 and $0.9 million as of December 31, 2025.

Bristol Myers Squibb Company

Effective July 7, 2014, the Company entered into a collaboration and license agreement with Bristol Myers Squibb Company ("Bristol Myers Squibb") to discover, develop, and commercialize PROBODY therapeutics against multiple oncology targets, including CTLA-4, which was subsequently expanded in 2017 and amended in 2021 to include additional targets and extended research activities. Under the collaboration, the Company received aggregate upfront and milestone payments of $297.0 million and was eligible for additional development, regulatory, commercial milestone payments, and royalties on future product sales.

In 2024, Bristol Myers Squibb discontinued development of its lead CTLA-4 program, BMS-986288, and reduced the scope of certain preclinical research activities under the collaboration. The Company's research obligations for the remaining programs were completed in April 2025, resulting in recognition of the remaining deferred revenue of $11.6 million, and Bristol Myers Squibb subsequently terminated the collaboration in May 2026 after electing not to advance the remaining preclinical programs.

ModernaTX, Inc.

The Company and ModernaTX, Inc. (“Moderna”) entered into a Collaboration and License Agreement (the “Moderna Agreement”) on December 30, 2022, the effective date, to collaborate on discovery and preclinical research and development activities to create investigational messenger RNA (“mRNA”) based conditionally activated therapies using the Company’s PROBODY therapeutic technology. Moderna is solely responsible for the development (preclinical and clinical), manufacturing, and commercialization of any products under the Moderna Agreement.

Under the terms of the Moderna Agreement, the Company granted Moderna an exclusive, worldwide right to develop and commercialize PROBODY therapeutics for the collaboration programs. In exchange, the Company received an upfront payment of $35.0 million in January 2023, including $5.0 million of prepaid research and development service fees. The Company will continue to receive research and development service fees according to the preclinical research work plans based on a prescribed FTE rate and is eligible to receive up to approximately$1.2 billion in future development, regulatory, and commercial milestone payments. The Company is also eligible to receive tiered royalties from high-single digit to low-teen percentage rates of annual global net sales of any products that are commercialized under the Moderna Agreement.

Due to Moderna's budget considerations, the Company's remaining activities for its performance obligation are currently paused pending future alignment with Moderna. As of June 30, 2026 and December 31, 2025, deferred revenue relating to the Moderna Agreement was$9.3 million and $9.3 million, respectively. There wasno amountdue from Moderna under the Moderna Agreement as of June 30, 2026 and December 31, 2025.

Regeneron Pharmaceuticals, Inc.

The Company and Regeneron Pharmaceuticals Inc. (“Regeneron”) entered into a Collaboration and License Agreement (the “Regeneron Agreement”) on November 16, 2022, to collaborate on creation of conditionally-activated investigational bispecific cancer therapies utilizing the Company’s PROBODY therapeutic platform and Regeneron’s Veloci-Bi® bispecific antibody development platform. The Company and Regeneron will collaborate on preclinical research and discovery activities for initially agreed upon collaboration programs (“Collaboration Program”) with an option to expand additional Collaboration Programs (“Additional Collaboration Program Option”).

Under the Regeneron Agreement, the Company granted Regeneron an exclusive, worldwide, royalty-bearing license under certain Company intellectual property to develop, manufacture, commercialize and otherwise exploit licensed products (“Licensed Products”) for all human and non-human diagnostic, prophylactic and therapeutic uses in oncology. Regeneron is responsible for funding the cost of preclinical research and discovery activities of both parties for all Licensed Products and for funding the cost of development, manufacturing and commercialization of all Licensed Products worldwide.

Pursuant to the Regeneron Agreement, the consideration from Regeneron was comprised of an upfront fee of $30.0 million, contingent payments for development and regulatory milestones and commercial milestone payments of up to an aggregate of approximately $0.8 billion. If Regeneron exercised its Additional Collaboration Program Option, the Company would have been eligible to receive additional upfront and milestone payments aggregating up to approximately $1.2 billion.

In May 2026, the Company and Regeneron amended the Regeneron Agreement (the "Amendment") primarily to (1) extend the program selection period for Regeneron to select its additional Collaboration Programs for research and development, and (2) expand the total number of additional Collaboration Programs from three toeight targets. Of the eight Collaboration Programs and pursuant to the Amendment, two targets were selected in June 2026 for an aggregate upfront fee of $37.0 million, with contingent payments for development and regulatory milestones and commercial milestone payments of up to an aggregate of approximately $0.8 billion.

Pursuant to the Amendment, if Regeneron exercises all Additional Collaboration Program Options, the Company is eligible to receive total upfront, development, regulatory and commercial milestone payments aggregating up to approximately $4.0 billion. The Company is also entitled to tiered royalties from high-single digit to low-teen percentage royalties from potential future sales. In addition, the Company will receive research and development service fees based on a prescribed FTE rate.

The Company determined that each selected Collaboration Program was a distinct performance obligation consisting of an exclusive research, development and commercialization license, research and development services and participation in the joint research committee. The Company concluded that as of the effective date of the Amendment, the final two targets were material rights and performance obligations. The Company accounted for the Amendment as a contract modification and allocated the total unrecognized transaction price among the identified performance obligations using the relative standalone selling price (“SSP”) of each performance obligation. The total unrecognized transaction price as of the effective date of the Amendment was $56.4 million, consisting of the upfront fee of $37.0 million, estimated research and development service fees of $10.0 million and unrecognized transaction price at the time of the modification of $9.4 million. To determine the SSP, the Company considered observable collaboration transactions, adjusted for differences in stage of development, modality, scope of rights transferred, expected research effort, market conditions, and Company-specific circumstances known as of the modification date. The transaction price allocated to each performance obligation is recognized using an input measure over the estimated research service period of four years consistent with the Company’s related accounting policy. The Company determined that the contingent milestone payments were fully constrained due to the uncertainty in achieving them as of the inception of the Amendment.

As of June 30, 2026 and December 31, 2025, deferred revenue relating to the Regeneron Agreement was$45.4 million and $10.5 million, respectively. The amount due from Regeneron under the Regeneron Agreement was $37.5 million and $0.8 million as of June 30, 2026 and December 31, 2025, respectively. The $37.0 million upfront fee was collected in July 2026.

Contract Liabilities

The following table presents changes in the Company’s total contract liabilities during the six months ended June 30, 2026 and 2025:

The Company expects that the$54.7 million of deferred revenue related to the following contracts as of June 30, 2026 will be recognized as revenue based on actual FTE effort and estimated program progress as set forth below. However, the timing of revenue recognition could differ from the estimates depending on facts and circumstances impacting the various contracts, including progress of research and development, resources assigned to the contracts by the Company or its collaboration partners or other factors outside of the Company’s control.

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The$9.3 million of deferred revenue related to the Moderna Agreement, together with research and development service fees, are expected to be recognized primarily in 2026 and 2027.

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The$45.4 million of deferred revenue related to the Regeneron Agreement, together with research and development service fees, are expected to be recognized until 2030.

7. License Agreement

UCSB Agreement

In August 2010, the Company entered into an exclusive, worldwide license agreement with University of California, Santa Barbara (“UCSB”), relating to the use of certain patents and technology, and to patent rights the Company co-owns with UCSB that cover certain conditionally activatable antibodies (the “UCSB Agreement”). Pursuant to the UCSB Agreement, the Company has annual minimum royalty obligations of $0.2 million under the terms of certain exclusive licensed patent rights. In April 2019, the Company entered into Amendment No. 3 to the UCSB Agreement to adjust and clarify certain sublicense terms (“Amendment No. 3”). Under the terms of Amendment No. 3, the Company agreed to make an additional annual license maintenance fee of $0.8 million through January 2031. In the event that the Company terminates the agreement due to material concern of the safety or efficacy of the related technology,50% of all remaining maintenance fees will become due immediately. Otherwise, all remaining maintenance fees will become due immediately upon early termination of the agreement unless there is a material breach by UCSB.

No license or sublicense expenses were incurred during the three months ended June 30, 2026 and 2025. For the six months ended June 30, 2026 and 2025, the Company incurred license and sublicense expenses of $0.9 million and $1.1 million, respectively, under the UCSB Agreement.

ImmunoGen (acquired by AbbVie in 2024)

In December 2019, the Company entered into a License Agreement (the “ImmunoGen 2019 License”) with ImmunoGen, Inc. to obtain an exclusive license with respect to epithelial cell adhesion molecule (“EpCAM”). Under the ImmunoGen 2019 License, ImmunoGen agreed to transfer its know-how, patents, intellectual property rights, and technology transfer materials and information related to its EpCAM program. The license gives the Company the sole ability to develop, manufacture, use and commercialize any licensed product that incorporates, is comprised of, or otherwise derived from PROBODY technology that targets EpCAM in any human therapeutic field on a worldwide basis. In exchange, the Company made an upfront license payment of $7.5 million, and will pay up to $35.0 million in certain clinical development milestones and up to $320.0 million in regulatory approval and commercial milestone payments, if achieved. ImmunoGen is also entitled to royalties on product sales ranging from the mid-to-high single digits percentages.

In April 2024, the Company made a $5.0 million payment of the $35.0 million in potential clinical development milestone payments to AbbVie (formerly ImmunoGen) with respect to achieving the milestone of dosing the first patient for Varseta-M under the ImmunoGen 2019 License. The remaining $30.0 million of potential development milestone payments under the License Agreement are expected to be triggered by the start of the first Phase 2 study and first Phase 3 study for an EpCAM program (e.g. Varseta-M) in the amounts of $10.0 million and $20.0 million, respectively.

Varseta-M, which is currently in Phase 1 development, is covered under the ImmunoGen License Agreement.

8. Common Stock

On March 19, 2026, the Company completed an underwritten offering of 45,990,567 shares of common stock at an offering price of $5.30 per share and pre-funded warrants to purchase 1,179,245 shares of common stock (the “Pre-Funded Warrants”) at a price of $5.29999 per share. The Pre-Funded Warrants have an exercise price of $0.00001 per share, subject to adjustments, and are exercisable from the date of issuance until fully exercised, subject to an ownership limitation. The aggregate net proceeds received by the Company from the offering were approximately $234.2 million, after deducting underwriting discounts and commissions of $15.0 million and offering expenses of $0.8 million. In addition, the Company granted the underwriters the option for 30 days to purchase up to an additional 7,075,471 shares of common stock at the public offering price of $5.30 per share. Such option expired unexercised in April 2026.

In May 2025, the Company completed an underwritten public offering of 76,923,076 shares of common stock at a price of $1.30 per share. The aggregate net proceeds received by the Company from the offering were approximately $93.4 million, after deducting underwriting discounts and commissions of $6.0 million and offering expenses of $0.6 million. Longitude Venture Partners V, L.P. (“LVPV”) acquired approximately 11.5 million shares of common stock through the underwritten public offering. Longitude Capital Partners V, LLC (“LCPV”) is a general partner of LVPV. A member of the Company’s board of directors serves as a managing director of LCPV, and therefore, LCPV is considered a related party of the Company. The Company had no other significant related party transactions with LCPV.

In June 2023, the Company entered into an agreement with BVF Partners L.P. (“BVF”) for a private placement and received aggregate net proceeds of approximately $29.7 million in July 2023, after deducting issuance costs of approximately $0.3 million. In the private placement, the Company issued pre-funded warrants to BVF to purchase up to 14,423,077 shares of common stock (the “BVF Pre-Funded Warrants”), accompanying Tranche 1 warrants to purchase up to 5,769,231 shares of common stock and accompanying Tranche 2 warrants to purchase up to 5,769,231 shares of common stock, at a combined price of $2.08 per share. The initial exercise price of the Tranche 1 and Tranche 2 warrants was $4.16 per share and $6.24 per share, respectively. The public offering in May 2025 described above triggered an adjustment provision in the Tranche 1 and Tranche 2 warrants, pursuant to which the exercise prices were reduced to $2.73 and $3.77 per share, respectively. The Tranche 1 and Tranche 2 warrants expired without being exercised in July 2025 and July 2026, respectively. BVF exercised the BVF Pre-Funded Warrants for 7.5 million shares of common stock in May 2024 and for the remaining 6.9 million shares in May 2025, in each case at an exercise price of $0.00001 per share.

The following table summarizes the Company's outstanding warrants as of June 30, 2026:

In the June 2026 annual meeting of stockholders, the Company's authorized shares of common stock were approved to increase from 300,000,000 shares to 600,000,000 shares.

9. Stock-Based Compensation

Stock Options

Activities for the Company’s stock option plans for the six months ended June 30, 2026 were as follows:

The Company recorded $1.7 million and $0.8 million of stock-based compensation expense related to the stock option plans for the three months ended June 30, 2026 and 2025, respectively.

The Company recorded $5.4 million and $2.0 million of stock-based compensation expense related to the stock option plans for the six months ended June 30, 2026 and 2025, respectively.

Time-based RSUs ("TRSU")

Activities for the Company’s TRSUs for the six months ended June 30, 2026 were as follows:

The Company recorded $0.8 million and $0.5 million of stock-based compensation expense related to the TRSUs for the three months ended June 30, 2026 and 2025, respectively.

The Company recorded $1.7 million and $0.6 million of stock-based compensation expense related to the TRSUs for the six months ended June 30, 2026 and 2025, respectively.

Performance-based RSUs ("PSUs")

2024 PSU

In January 2024, the Company granted 810,000 PSUs to executive employees with an aggregate grant date fair value of approximately $1.3 million. Vesting for 50% of the PSUs granted would occur upon attaining specified milestones by December 2025 (“2024-Tranche-1 PSUs”), and the remaining 50% will vest upon attaining specified milestones by December 2026 (“2024-Tranche-2 PSUs”). The 2024-Tranche-1 PSUs were canceled as the related performance condition was not met by December 2025. As of June 30, 2026, the Company determined that it is not probable that the performance conditions will be satisfied for 2024-Tranche-2 PSUs and henceno compensation cost was recorded for these awards through June 30, 2026.

2025 PSU

In September 2025 and February 2026, the Company granted a total of 463,350 PSUs to executive employees with an aggregate grant date fair value of approximately $1.5 million. Vesting for one-third of the PSUs granted will occur upon attaining a specified milestone (“2025-Tranche-1 PSUs”), vesting for one-third of the PSUs granted will occur upon attaining a specified milestone (“2025-Tranche-2 PSUs”) on June 30, 2027 or later, and the remaining one-third will vest upon attaining a specified milestone on June 30, 2028 or later (“2025-Tranche-3 PSUs”). As of June 30, 2026, the Company determined that it is not probable that the performance conditions will be satisfied for any of these tranches and henceno compensation cost was recorded for these awards through June 30, 2026.

Activities for the Company’s PSUs for the six months ended June 30, 2026, were as follows:

Stock-based Compensation

Total stock-based compensation recorded was as follows:

During the six months ended June 30, 2026, in connection with the extension of consulting arrangements for two former executives, the Company extended the vesting period of unvested options and awards and the exercisable period of vested options, as permitted under the Company's equity incentive plans. As a result, the Company recognized the full amount of the incremental stock-based compensation expense of approximately $2.5 million in the six months ended June 30, 2026.

10. Leases

2016 Lease Operating Lease

In December 2015, the Company entered into a lease (the “2016 Lease”) of office and laboratory space located in South San Francisco, California for the Company’s corporate headquarters. The 2016 Lease has an initial term often years through September 2026 and the Company had an option to extend the initial term for an additional five years at the then fair rental value as determined pursuant to the 2016 Lease. In addition, the Company obtained a standby letter of credit (the “Letter of Credit”) in an amount of approximately $0.9 million, which may be drawn by the Landlord prior to its expiration on December 31, 2026, to be applied for certain purposes upon the Company’s breach of any provisions under the 2016 Lease. The Company recorded $0.9 million of cash securing the Letter of Credit as current restricted cash and non-current restricted cash on its balance sheets as of June 30, 2026 and December 31, 2025, respectively. In January 2026, the Company and the sublease tenant entered into a sublease termination agreement, resulting in an early termination of the sublease in February 2026. Pursuant to the sublease termination agreement, the sublessee paid an aggregate of $0.6 million as final settlement of the sublease, of which $0.2 million was included as an offset against operating lease cost for the first quarter of 2026.

During the three and six months ended June 30, 2026, under the 2016 Lease, rent expensewas $1.2 million and $2.2 million, respectively and related variable lease cost was $0.7 million and $1.4 million, respectively. As of June 30, 2026 and December 31, 2025, the oper ating lease ROU asset was $1.1 million and $3.4 million, respectively. The lease liability all due within 2026 was $1.4 million and $4.2 million as of June 30, 2026 and December 31, 2025, respectively.

2026 Lease Operating Lease

In November 2025, the Company entered into a lease (the “2026 Lease”) of office and laboratory space located in Emeryville, California for the Company’s corporate headquarters. The contractual term for the 2026 Lease is October 1, 2026 to December 31, 2029. The Company determined that the lease commencement date for accounting purposes is April 1, 2026, when the office and laboratory space is available for use by the Company to begin construction of its leasehold improvements, and resulted in recognition of approximately $4.1 million lease liabilities and the related right of use assets. The Company expects to utilize the full amount of the one-time tenant improvement allowance of $0.4 million receivable from landlord. The Company hastwo options to extend the term, each for an additional two years, at the then fair market rent as determined under the term of the 2026 Lease. In addition, the Company has provided a security deposit of $0.5 million or letter of credit with anticipated reduction to $0.3 million at the end of December 2026, which may be drawn by the Landlord to be applied for certain purposes upon the Company’s breach of any provisions under the 2026 Lease. The Company has recorded the $0.5 million Letter of Credit as non-current restricted cash on its balance sheet as of June 30, 2026 and December 31, 2025.

Rent expense is recognized on a straight-line basis over the term of the lease and accordingly the Company records the difference between cash rent payments and the recognition of rent expense against the operating lease ROU asset. Rent expense under the 2026 Lease during the three months ended June 30, 2026 was $0.4 million.

Supplemental information related to the 2026 Lease are as follows:

11. Income Taxes

The Company maintains a full valuation allowance against its net deferred tax assets through June 30, 2026.

The Company files income taxes in the U.S. federal jurisdiction, the state of California and various other U.S. states. The state of California contested the Company’s tax position on revenue apportionment for upfront and milestone payments resulting from the Company’s collaboration and licensing agreements for the years 2017 and 2018. In September 2023, the Company received Notice of Proposed Assessment (“NOPA”) from the Franchise Tax Board. The Company recorded an uncertain tax position of$4.5 million in long-term liabilities for the proposed tax assessment, penalties and interest through June 30, 2026. Additional utilization of carryforward attributes and indirect federal tax effects of the assessment would result in a reduction in deferred tax assets of $5.0 million. The Company filed a protest to contest the proposed assessment in November 2023. Due to the ongoing nature of the examination and discussions with the state of California, the Company is unable to estimate a date by which this matter will be resolved.

12. Segment Disclosures

The Company operates as asingle operating segment. The Chief Executive Officer is identified as the Chief Operating Decision Maker (“CODM”). The CODM primarily reviews the Company’s financial information on an aggregate basis. The CODM utilizes the aggregated financial information to make strategic decisions, assess performance, and allocate resources across the Company. The aggregate information includes the revenue by collaboration partner, research and development expense by program, as well as net income (loss) that is reported on the Statements of Operations and Comprehensive Income (Loss). Net income (loss) is used to monitor budget versus actual results in assessing performance of the segment and in establishing management's compensation. The measure of segment assets is reported on the Balance Sheets as total assets. All of the Company’s long-lived assets are located in the United States. In addition to the revenue by collaborative partners disclosed in Note 6, the CODM reviews the following significant expenses in making decisions about the allocation of resources and assessing performance (in thousands):