Summary of Significant Accounting Policies (Policies)	12 Months Ended
Dec. 31, 2025
Summary of Significant Accounting Policies
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The accompanying consolidated financial statements include the operations of the Company and its wholly-owned subsidiaries. All intercompany accounts, transactions, and balances have been eliminated in consolidation. The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets, liabilities, expenses, and related disclosures. The Company bases its estimates on historical experience, known trends and other market- specific factors or other relevant factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis using such factors and adjusts those estimates and assumptions as facts and circumstances dictate. Actual results may differ from those estimates or assumptions. Significant estimates in these consolidated financial statements include estimates made in connection with accrued research and development expenses, stock-based compensation, pre-IPO valuations of common stock, and the liability related to the sale of future royalties including the estimation of future payments and the related non-cash interest expense.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with original or remaining maturity from the date of purchase of three months or less to be cash equivalents. Cash equivalents may include money market funds, corporate debt securities, U.S government agency notes and overnight deposits.
Investments	Investments The Company classifies all investments with a remaining maturity when purchased of greater than three months as “available-for-sale”. Available-for-sale securities with a remaining maturity of greater than one year are classified as non-current assets. Available-for-sale securities are carried at fair value based upon market prices at period end, with the unrealized gains and losses included in accumulated other comprehensive loss as a component of stockholders’ equity (deficit) until realized. The amortized cost of investments in this category is adjusted for amortization of premiums and accretions of discounts over the life of the instrument. Realized gains and losses are determined using the specific identification method and are included in other income (expense). The Company reviews its portfolio of investments, using both quantitative and qualitative factors, to determine if declines in fair value below cost have resulted from a credit-related loss. If the decline in fair value is due to credit-related factors, a loss is recognized in other income (expense).
Restricted Cash	Restricted Cash Restricted cash consists of cash held as collateral for a letter of credit the Company issued as a security deposit for its lease of office space in Waltham, MA, which was terminated in January 2025. Amounts are reported as non-current unless restrictions are expected to be released in the next 12 months.
Deferred Offering Costs	Deferred Offering Costs The Company capitalizes legal, professional accounting and other third-party fees that are directly associated with in-process equity financings as other non-current assets until such financings are consummated. After consummation of the equity financing, these costs will be recorded in stockholders’ equity (deficit) as a reduction of additional paid-in-capital generated as a result of the offering. If the Company terminates its plan for an equity financing, any costs deferred will be expensed immediately. As of December 31, 2025, the Company had $0.7 million in deferred offering costs which were included in other assets. No deferred offering costs were recorded as of December 31, 2024.
Segment Reporting	Segment Reporting Operating segments are defined as components of an enterprise for which separate and discrete information is available for evaluation by the chief operating decision-maker in deciding how to allocate resources and assess performance. The Company has one reportable segment focused on the research and development of precision immunology-based therapies. The Company’s chief operating decision-maker (the “CODM”), its Chief Executive Officer, manages the Company’s operations on a consolidated basis for the purposes of making operating decisions, assessing financial performance, and allocating resources. As of December 31, 2025 and 2024, the Company’s long-lived assets held outside of the U.S. were immaterial. For additional information, see Note 17, Segment Information to these consolidated financial statements.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash, cash equivalents and investments. The Company attempts to minimize the risks related to cash, cash equivalents and investments by investing in a broad range of financial instruments, as defined by the Company’s investment policy. The Company has established guidelines related to the quality of the institutions, financial instruments and allowable investments. The Company minimizes credit risk by choosing only highly rated financial institutions as counterparties.
Significant Suppliers	Significant Suppliers The Company is dependent on third-party manufacturers to supply products for research and development activities in its programs, including preclinical and clinical studies and testing. While the drug substances used in product candidates are manufactured by more than one supplier, the Company relies on a single third-party manufacturer to manufacture and supply it with its requirements for the drug product related to its programs. These programs could be adversely affected by a significant interruption in the supply of drug substance and drug product.
Translation of Foreign Currency	Translation of Foreign Currency The functional currency for most of our foreign subsidiaries is their local currency. For our non-U.S subsidiaries that transact in a functional currency other than the U.S. dollar, assets and liabilities are translated at current rates of exchange at the balance sheet date. Income and expense items are translated at the average foreign currency exchange rates for the period. Adjustments resulting from the translation of the financial statements of our foreign subsidiaries into U.S. dollars are excluded from our determination of net loss and are recorded in accumulated other comprehensive income (loss), as a separate component of equity. For foreign subsidiaries where the functional currency of assets and liabilities differs from their local currency, non-monetary assets and liabilities are translated at the rate of the exchange in effect on the date assets were acquired while monetary assets and liabilities are translated at current rates of exchange as of the balance sheet date. Income and expense items are translated at the average foreign currency rates for the period. Translation adjustments of these subsidiaries are included in other (income) expense, net in our consolidated statements of income. Realized and unrealized foreign currency transaction gains were $0.3 million and transaction losses were $0.2 million for the years ended December 31, 2025 and 2024, respectively.
Fair Value Measurements	Fair Value Measurements ASC Topic 820, Fair Value Measurement (“ASC 820”), establishes a fair value hierarchy for instruments measured at fair value that distinguishes between assumptions based on market data (observable inputs) and the Company’s own assumptions (unobservable inputs). Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the assets or liability and are developed based on the best information available in the circumstances. ASC 820 identifies fair value as the price that would be received to sell an asset or paid to transfer a liability, in an orderly transaction between market participants at the measurement date. As a basis for considering market participant assumptions in fair value measurements, ASC 820 establishes a three-tiered value hierarchy that distinguishes between the following: Level 1— Quoted market prices in active markets for identical assets or liabilities. Level 2— Inputs other than Level 1 inputs that are either directly or indirectly observable, such as quoted market prices, interest rates and yield curves. Level 3— Unobservable inputs for the asset or liability (i.e. supported by little or no market activity). Level 3 inputs include management’s own assumptions about the assumptions that market participants would use in pricing the asset or liability (including assumptions about risk). To the extent the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair values requires more judgement. Accordingly, the degree of judgement exercised by the Company in determining fair value is greatest for instruments categorized as Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The majority of the Company’s financial assets have been classified as Level 1. Our financial assets (which typically include cash equivalents and marketable debt securities) have been initially valued at the transaction price and subsequently valued, at the end of each reporting period, utilizing third-party pricing services or option pricing valuation models. The pricing services utilize industry standard valuation models, including both income and market-based approaches and observable market inputs to determine value. These observable market inputs may include reportable tables, benchmark yields, broker quotes, bids, offers, current spot rates and other industry and economic events. For additional information, see Note 3, Fair Value Measurements to these consolidated financial statements.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. When such events occur, the Company compares the carrying amount of the assets to their undiscounted expected future cash flows. If this comparison indicates there is an impairment, the amount of the impairment is calculated as the difference between the carrying value and fair value. To date, no such impairments have been recognized.
Property and Equipment	Property and Equipment Property and equipment are recorded at cost. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets (three to seven years). Leasehold improvements are amortized over the shorter of their useful lives or lease terms using the straight-line method. Major replacements and improvements are capitalized, while general repairs and maintenance are expensed as incurred.
Royalty Obligation	Royalty Obligation When the Company maintains significant continuing involvement in generating the underlying cash flows, royalty financings are recognized as obligations. Payments received are recorded as the principal amount of the obligation on the consolidated balance sheet as long-term liabilities. The carrying amount of the obligation is accreted to reflect the total expected royalty and related payments, using the effective interest method. As royalties and other related payments are made, the outstanding royalty obligation will be reduced over the estimated term of the arrangement. The royalty obligation, effective interest rate, and corresponding interest expense are determined based on the Company’s estimate of future anticipated royalty payments under the arrangement. These estimates are reassessed at the end of each reporting period according to the Company’s latest projections. Should these estimated cash flows change as a result of this review, the Company will recalculate the effective interest rate and adjust the accretion of interest on the royalty obligation prospectively. Any additional funding received will also be treated as an obligation, with a prospective adjustment to the effective interest rate applied upon receipt of such funds. For additional information, see Note 9, Royalty Obligation to these consolidated financial statements.
License and Collaboration Revenue	License and Collaboration Revenue The Company enters into license and collaboration arrangements with third parties, under which the Company licenses or may license rights to certain of the Company’s product candidates and may perform research and development services in connection with such arrangements. The terms of these arrangements typically include payment of one or more of the following: non-refundable, upfront fees; reimbursement of research and development costs; development, clinical, regulatory and commercial sales milestone payments, and royalties on net sales of licensed products. At contract inception, the Company analyzes its collaboration and license arrangements to assess whether such arrangements are within the scope of ASC Topic 808, Collaborative Arrangements (“ASC 808”). This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For collaboration arrangements within the scope of ASC 808 that contain multiple units of account, the Company first determines which units of the collaboration are deemed to be within the scope of ASC 808 and which units of the collaboration are more reflective of a vendor-customer relationship and therefore within the scope of ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”). Contracts are considered to be collaborative arrangements when they satisfy the following criteria defined in ASC 808: (i) the parties to the contract must actively participate in the joint operating activity and (ii) the joint operating activity must expose the parties to the possibility of significant risks and rewards, based on whether or not the activity is successful. For elements of collaboration arrangements that are accounted for pursuant to ASC 808, an appropriate recognition method is determined and applied consistently, either by analogy to authoritative accounting literature or by applying a reasonable and rational policy election. Payments received from or made to a partner that are the result of a collaborative relationship with a partner, instead of a customer relationship, such as co-development activities, are recorded as a reduction or increase to research and development expense, respectively. For the units of account within the scope of ASC 606, to determine the appropriate amount of revenue to be recognized for the arrangements, the Company performs the following five steps: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations including whether they are distinct; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect consideration it is entitled to in exchange for the goods or services it transfers to the customer. The promised goods or services in the Company’s arrangements typically consist of a license to the Company’s intellectual property and research and development services. The Company provides options to additional items in such arrangements, which are accounted for as separate contracts when the customer elects to exercise such options, unless the option provides a material right to the customer. Performance obligations are promised goods or services in a contract to transfer a distinct good or service to the customer and are considered distinct when (i) the customer can benefit from the good or service on its own or together with other readily available resources and (ii) the promised good or service is separately identifiable from other promises in the contract. In assessing whether promised goods or services are distinct, the Company considers factors such as the stage of development of the underlying intellectual property, the capabilities of the customer to develop the intellectual property on its own or whether the required expertise is readily available and whether the goods or services are integral or dependent to other goods or services in the contract. The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration and variable consideration. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of potential payment and the likelihood that the payments will be received. The Company utilizes either the most likely amount method or expected value method to estimate the amount expected to be received based on which method best predicts the amount expected to be received. The amount of variable consideration that is included in the transaction price may be constrained and is included in the transaction price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. The Company’s contracts often include development and regulatory milestone payments that are assessed under the most likely amount method and constrained if it is probable that a significant revenue reversal would occur. Due to the uncertainty of research and development and regulatory based milestones that are not within the control of the Company, payment becomes probable upon achievement. At the end of each reporting period, the Company re-evaluates the probability of achievement of such development and clinical milestones and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license and collaboration revenue in the period of adjustment. Any amounts due to the Company but not received as of period-end will be recorded to other current assets. For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). To date, the Company has not recognized any royalty revenue resulting from any of the Company’s collaboration arrangements. The Company allocates the transaction price based on the estimated standalone selling price. The Company must develop assumptions that require judgment to determine the stand-alone selling price for each performance obligation identified in the contract. The Company utilizes key assumptions to determine the stand-alone selling price, which may include other comparable transactions, pricing considered in negotiating the transaction and the estimated costs including a reasonable margin. Variable consideration is allocated specifically to one or more performance obligations in a contract when the terms of the variable consideration relate to the satisfaction of the performance obligation and the resulting amounts allocated are consistent with the amounts the Company would expect to receive for the satisfaction of each performance obligation. The consideration allocated to each performance obligation is recognized as revenue when control is transferred for the related goods or services.
Research and Development Expenses	Research and Development Expenses Research and development costs include (i) employee-related expenses, including salaries, benefits, and stock-based compensation expense; (ii) external research and development expenses incurred under arrangements with third parties, such as contract research organization (“CROs”) agreements and consultants; (iii) costs associated with preclinical activities and (iv) lab supplies, lab expenses and an allocation of rent, depreciation, and infrastructure. Costs incurred in connection with research and development activities are expensed as incurred. Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data, such as patient enrollment or clinical site activations, provided by the Company’s clinical sites and vendors. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. Depending upon the timing of payments to the service providers, the Company recognizes prepaid expenses or accrued expenses related to these costs. These accrued or prepaid expenses are based on management’s estimates of the work performed under service agreements, milestones achieved, and experience with similar contracts. Milestone payments under license agreements are accrued, with a corresponding expense being recognized, in the period in which the milestone is determined to be probable of achievement and the related amount is reasonably estimable. The Company monitors each of these factors and adjusts estimates accordingly. The Company has not experienced any material differences between accrued costs and actual costs incurred since its inception.
Asset Acquisitions and Acquired In-Process Research and Development Expense	Asset Acquisitions and Acquired In-Process Research and Development Expense The Company accounts for acquisitions of assets or a group of assets that do not meet the definition of a business as asset acquisitions based on the cost to acquire the asset or group of assets, which include certain transaction costs. In an asset acquisition, the cost to acquire is allocated to the identifiable assets acquired and liabilities assumed based on their relative fair values as of the acquisition date. No goodwill is recorded in an asset acquisition. Assets that are acquired in an asset acquisition for use in research and development activities that have an alternative future use are capitalized as in process research and development (“IPR&D”). Acquired IPR&D that has no alternative future use as of the acquisition date is recognized as acquired IPR&D expense as of the acquisition date. The Company will recognize additional acquired IPR&D expenses in the future if and when the Company becomes obligated to make contingent milestone payments under the terms of the agreements by which it acquired the IPR&D assets. The Company classifies payments made for the acquisition of IPR&D assets, whether capitalized or expensed, as investing activities on its statement of cash flows. Contingent consideration in the form of milestone payments related to IPR&D with no alternative future use are charged to expense when the related milestone is achieved and becomes payable. When milestone payments are in the form of equity consideration, the Company evaluates whether the payment should be treated as a liability or meets the definition of a derivative. When liability or derivative treatment is not required, such milestone payments are recorded at fair value as a component of equity and not remeasured. For additional information, see Note 8, License Agreements, to these consolidated financial statements.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. Comprehensive loss consists of net loss and other comprehensive loss. During the years ended December 31, 2025 and 2024, the Company’s only element of other comprehensive loss was foreign currency translation adjustments.
Leases	Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in right-of use lease assets (“ROU assets”), current portion of lease obligations and long-term lease obligations on the Company’s consolidated balance sheet. Assets subject to finance leases are included in property and equipment, and the related lease obligation is included in other current liabilities and other long-term liabilities on the Company’s consolidated balance sheet. Lease assets are tested for impairment in the same manner as long-lived assets used in operations. Lease expense for operating leases is recognized on a straight-line basis over the lease term as an operating expense, while expense for financing leases is recognized as depreciation expense (classified as an operating expense) and interest expense (classified as a non-operating expense) using the effective interest method. The Company has elected the short-term lease recognition exemption for short-term leases, which allows the Company not to recognize lease liabilities and ROU assets on the consolidated balance sheet for leases with an original term of twelve months or less. ROU assets represent the Company’s right to use an underlying asset for the lease term, and lease obligations represent the Company’s obligation to make lease payments arising from the lease. Operating lease liabilities and their corresponding ROU assets are initially recognized based on the present value of lease payments over the expected remaining lease term. When determining the lease term, the Company includes options to extend or terminate the lease when it is reasonably certain that the Company will exercise the option. Certain adjustments to the ROU asset may be required for items such as incentives received from the lessor. The interest rate implicit in lease contracts is typically not readily determinable. Therefore, the Company utilizes its incremental borrowing rate to discount lease payments. The incremental borrowing rate reflects the fixed rate at which the Company could borrow, on a collateralized basis, the amount of the lease payments in the same currency, for a similar term, in a similar economic environment. Prospectively, the Company will adjust the ROU assets for straight-line rent expense, or any incentives received and remeasures the lease liability at the net present value using the same incremental borrowing rate that was in effect as of the lease commencement or transition date. The Company generally accounts for non-lease components together with lease components. The Company expenses variable payments included in a lease arrangement as such expenses are incurred. For additional information, see Note 6, Leases, to these consolidated financial statements.
Income Taxes	Income Taxes The Company accounts for income taxes in accordance with ASC Topic 740, Accounting for Income Taxes, which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. The Company determines its deferred tax assets and liabilities based on differences between financial reporting and tax bases of assets and liabilities, which are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. Valuation allowances are provided if, based upon the weight of available evidence, it is more likely than not that some or all deferred tax assets will not be realized. The Company accounts for uncertain tax positions recognized in the consolidated financial statements by prescribing a “more likely than not” threshold for financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. There are no unrecognized tax benefits included in the Company’s consolidated balance sheets as of December 31, 2025 and 2024. The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. The Company has not recognized interest or penalties related to uncertain tax positions in its consolidated statements of operations and comprehensive loss since inception.
Stock-Based Compensation	Stock-Based Compensation The Company grants stock-based awards to employees, non-employee consultants and members of its board of directors (the “Board”). Stock-based compensation is recognized as expense for each stock-based award based on its estimated fair value on the date of grant. The Company’s share-based payments include stock options, grants of restricted common stock and restricted stock units (“RSUs”). The value of the award is recognized as expense on a straight-line basis over the requisite service period, and expense is adjusted for pre-vesting forfeitures in the period in which the forfeitures occur. Stock-based compensation expense is classified in the accompanying consolidated statements of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipients service payments are classified. The Company estimates the fair value of each RSUs at its grant date based on the estimated fair value of the Company’s common stock on that date as determined by the Board. The Company estimates the fair value of stock option awards on the grant date using a Black-Scholes option pricing model. The Company estimates the expected option lives using the simplified method, volatility using historical stock prices of peer companies, the risk-free rates using the U.S Treasury yield curve in effect with a remaining term equal to the expected term and dividend yield based on the Company’s history of paying no dividends and the expectations of paying no cash dividends in the foreseeable future. Prior to the Company’s IPO, the fair value of the Company’s common stock on the date of grant was determined by the Board, taking into consideration its most recently available third-party valuations of common stock as well as additional factors which may have changed since the date of the most recent contemporaneous valuation through the grant date. For additional information, see Note 11, Stock-Based Compensation, to these consolidated financial statements.
Net Loss Per Share	Net Loss Per Share Basic net loss per share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed using the weighted-average number of common shares outstanding during the period and, if dilutive, the weighted-average number of potential shares of common stock. Net loss per share is calculated using the two- class method, which is an earnings allocation formula that determines net loss per share for the holders of the Company’s common shares and participating securities. The Company’s convertible preferred stock contained participation rights in any dividend paid by the Company and was deemed to be a participating security. Net loss attributable to common stockholders and participating preferred shares are allocated to each share on an as-converted basis as if all of the earnings for the period had been distributed. The participating securities do not include a contractual obligation to share in losses of the Company and are not included in the calculation of net loss per share in the periods in which a net loss is recorded. Diluted net loss per share is computed using the more dilutive of (a) the two-class method or (b) the if- converted method. The weighted-average number of common shares included in the computation of diluted net loss per share gives effect to all potentially dilutive common equivalent shares, including outstanding stock options and preferred stock. Common stock equivalent shares are excluded from the computation of diluted net loss per share if their effect is antidilutive. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share is the same as basic net loss since dilutive common shares are not assumed to have been issued if their effect is antidilutive. The Company reported a net loss for the years ended December 31, 2025 and 2024.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740)—Improvements to Income Tax Disclosures (“ASU 2023-09”), which requires a company to expand its existing income tax disclosures, specifically related to the rate reconciliation and income taxes paid. ASU 2023-09 is effective for the Company beginning in fiscal year 2025. This standard became effective for the Company for the annual reporting period ended December 31, 2025, and was adopted using the prospective method. The adoption of this standard resulted in additional disclosure of the rate reconciliation. The adoption did not have a material impact on the consolidated financial position or results of operations. See Note 13, Income Taxes, to these consolidated financial statements, for our updated income tax presentation. In November 2024, the FASB issued 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”), which requires entities to disclose additional information about specific expense categories in the notes to the financial statements. ASU 2024-03 is effective annual for periods beginning after December 15, 2026 and for interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. ASU 2024-03 may be applied retrospectively or prospectively to the financial statements. The Company is currently evaluating the impact of ASU 2024-03 on the consolidated financial statements and related disclosures. From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that we adopt as of the specified effective date. Unless otherwise discussed, we do not believe that the adoption of recently issued standards have or may have a material impact on our consolidated financial statements or disclosures.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2025

Summary of Significant Accounting Policies

The accompanying consolidated financial statements include the operations of the Company and its wholly-owned subsidiaries. All intercompany accounts, transactions, and balances have been eliminated in consolidation. The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets, liabilities, expenses, and related disclosures. The Company bases its estimates on historical experience, known trends and other market- specific factors or other relevant factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis using such factors and adjusts those estimates and assumptions as facts and circumstances dictate. Actual results may differ from those estimates or assumptions. Significant estimates in these consolidated financial statements include estimates made in connection with accrued research and development expenses, stock-based compensation, pre-IPO valuations of common stock, and the liability related to the sale of future royalties including the estimation of future payments and the related non-cash interest expense.

Cash and Cash Equivalents

The Company considers all highly liquid investments with original or remaining maturity from the date of purchase of three months or less to be cash equivalents. Cash equivalents may include money market funds, corporate debt securities, U.S government agency notes and overnight deposits.

Investments

The Company classifies all investments with a remaining maturity when purchased of greater than three months as “available-for-sale”. Available-for-sale securities with a remaining maturity of greater than one year are classified as non-current assets. Available-for-sale securities are carried at fair value based upon market prices at period end, with the unrealized gains and losses included in accumulated other comprehensive loss as a component of stockholders’ equity (deficit) until realized. The amortized cost of investments in this category is adjusted for amortization of premiums and accretions of discounts over the life of the instrument. Realized gains and losses are determined using the specific identification method and are included in other income (expense). The Company reviews its portfolio of investments, using both quantitative and qualitative factors, to determine if declines in fair value below cost have resulted from a credit-related loss. If the decline in fair value is due to credit-related factors, a loss is recognized in other income (expense).

Restricted Cash

Restricted cash consists of cash held as collateral for a letter of credit the Company issued as a security deposit for its lease of office space in Waltham, MA, which was terminated in January 2025. Amounts are reported as non-current unless restrictions are expected to be released in the next 12 months.

Deferred Offering Costs

The Company capitalizes legal, professional accounting and other third-party fees that are directly associated with in-process equity financings as other non-current assets until such financings are consummated. After consummation of the equity financing, these costs will be recorded in stockholders’ equity (deficit) as a reduction of additional paid-in-capital generated as a result of the offering. If the Company terminates its plan for an equity financing, any costs deferred will be expensed immediately. As of December 31, 2025, the Company had $0.7 million in deferred offering costs which were included in other assets. No deferred offering costs were recorded as of December 31, 2024.

Segment Reporting

Operating segments are defined as components of an enterprise for which separate and discrete information is available for evaluation by the chief operating decision-maker in deciding how to allocate resources and assess performance. The Company has one reportable segment focused on the research and development of precision immunology-based therapies. The Company’s chief operating decision-maker (the “CODM”), its Chief Executive Officer, manages the Company’s operations on a consolidated basis for the purposes of making operating decisions, assessing financial performance, and allocating resources. As of December 31, 2025 and 2024, the Company’s long-lived assets held outside of the U.S. were immaterial.

For additional information, see Note 17, Segment Information to these consolidated financial statements.

Concentrations of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash, cash equivalents and investments. The Company attempts to minimize the risks related to cash, cash equivalents and investments by investing in a broad range of financial instruments, as defined by the Company’s investment policy. The Company has established guidelines related to the quality of the institutions, financial instruments and allowable investments. The Company minimizes credit risk by choosing only highly rated financial institutions as counterparties.

Significant Suppliers

The Company is dependent on third-party manufacturers to supply products for research and development activities in its programs, including preclinical and clinical studies and testing. While the drug substances used in product candidates are manufactured by more than one supplier, the Company relies on a single third-party manufacturer to manufacture and supply it with its requirements for the drug product related to its programs. These programs could be adversely affected by a significant interruption in the supply of drug substance and drug product.

Translation of Foreign Currency

The functional currency for most of our foreign subsidiaries is their local currency. For our non-U.S subsidiaries that transact in a functional currency other than the U.S. dollar, assets and liabilities are translated at current rates of exchange at the balance sheet date. Income and expense items are translated at the average foreign currency exchange rates for the period. Adjustments resulting from the translation of the financial statements of our foreign subsidiaries into U.S. dollars are excluded from our determination of net loss and are recorded in accumulated other comprehensive income (loss), as a separate component of equity. For foreign subsidiaries where the functional currency of assets and liabilities differs from their local currency, non-monetary assets and liabilities are translated at the rate of the exchange in effect on the date assets were acquired while monetary assets and liabilities are translated at current rates of exchange as of the balance sheet date. Income and expense items are translated at the average foreign currency rates for the period. Translation adjustments of these subsidiaries are included in other (income) expense, net in our consolidated statements of income. Realized and unrealized foreign currency transaction gains were $0.3 million and transaction losses were $0.2 million for the years ended December 31, 2025 and 2024, respectively.

Fair Value Measurements

ASC Topic 820, Fair Value Measurement (“ASC 820”), establishes a fair value hierarchy for instruments measured at fair value that distinguishes between assumptions based on market data (observable inputs) and the Company’s own assumptions (unobservable inputs). Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the assets or liability and are developed based on the best information available in the circumstances. ASC 820 identifies fair value as the price that would be received to sell an asset or paid to transfer a liability, in an orderly transaction between market participants at the measurement date.

As a basis for considering market participant assumptions in fair value measurements, ASC 820 establishes a three-tiered value hierarchy that distinguishes between the following:

Level 1— Quoted market prices in active markets for identical assets or liabilities.

Level 2— Inputs other than Level 1 inputs that are either directly or indirectly observable, such as quoted market prices, interest rates and yield curves.

Level 3— Unobservable inputs for the asset or liability (i.e. supported by little or no market activity). Level 3 inputs include management’s own assumptions about the assumptions that market participants would use in pricing the asset or liability (including assumptions about risk).

To the extent the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair values requires more judgement. Accordingly, the degree of judgement exercised by the Company in determining fair value is greatest for instruments categorized as Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement.

The majority of the Company’s financial assets have been classified as Level 1. Our financial assets (which typically include cash equivalents and marketable debt securities) have been initially valued at the transaction price and subsequently valued, at the end of each reporting period, utilizing third-party pricing services or option pricing valuation models. The pricing services utilize industry standard valuation models, including both income and market-based approaches and observable market inputs to determine value. These observable market inputs may include reportable tables, benchmark yields, broker quotes, bids, offers, current spot rates and other industry and economic events.

For additional information, see Note 3, Fair Value Measurements to these consolidated financial statements.

Impairment of Long-Lived Assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. When such events occur, the Company compares the carrying amount of the assets to their undiscounted expected future cash flows. If this comparison indicates there is an impairment, the amount of the impairment is calculated as the difference between the carrying value and fair value. To date, no such impairments have been recognized.

Property and Equipment

Property and equipment are recorded at cost. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets (three to seven years). Leasehold improvements are amortized over the shorter of their useful lives or lease terms using the straight-line method. Major replacements and improvements are capitalized, while general repairs and maintenance are expensed as incurred.

Royalty Obligation

When the Company maintains significant continuing involvement in generating the underlying cash flows, royalty financings are recognized as obligations. Payments received are recorded as the principal amount of the obligation on the consolidated balance sheet as long-term liabilities. The carrying amount of the obligation is accreted to reflect the total expected royalty and related payments, using the effective interest method. As royalties and other related payments are made, the outstanding royalty obligation will be reduced over the estimated term of the arrangement.

The royalty obligation, effective interest rate, and corresponding interest expense are determined based on the Company’s estimate of future anticipated royalty payments under the arrangement. These estimates are reassessed at the end of each reporting period according to the Company’s latest projections. Should these estimated cash flows change as a result of this review, the Company will recalculate the effective interest rate and adjust the accretion of interest on the royalty obligation prospectively. Any additional funding received will also be treated as an obligation, with a prospective adjustment to the effective interest rate applied upon receipt of such funds.

For additional information, see Note 9, Royalty Obligation to these consolidated financial statements.

License and Collaboration Revenue

The Company enters into license and collaboration arrangements with third parties, under which the Company licenses or may license rights to certain of the Company’s product candidates and may perform research and development services in connection with such arrangements. The terms of these arrangements typically include payment of one or more of the following: non-refundable, upfront fees; reimbursement of research and development costs; development, clinical, regulatory and commercial sales milestone payments, and royalties on net sales of licensed products.

At contract inception, the Company analyzes its collaboration and license arrangements to assess whether such arrangements are within the scope of ASC Topic 808, Collaborative Arrangements (“ASC 808”). This assessment is

performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For collaboration arrangements within the scope of ASC 808 that contain multiple units of account, the Company first determines which units of the collaboration are deemed to be within the scope of ASC 808 and which units of the collaboration are more reflective of a vendor-customer relationship and therefore within the scope of ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”).

Contracts are considered to be collaborative arrangements when they satisfy the following criteria defined in ASC 808: (i) the parties to the contract must actively participate in the joint operating activity and (ii) the joint operating activity must expose the parties to the possibility of significant risks and rewards, based on whether or not the activity is successful. For elements of collaboration arrangements that are accounted for pursuant to ASC 808, an appropriate recognition method is determined and applied consistently, either by analogy to authoritative accounting literature or by applying a reasonable and rational policy election. Payments received from or made to a partner that are the result of a collaborative relationship with a partner, instead of a customer relationship, such as co-development activities, are recorded as a reduction or increase to research and development expense, respectively.

For the units of account within the scope of ASC 606, to determine the appropriate amount of revenue to be recognized for the arrangements, the Company performs the following five steps: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations including whether they are distinct; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect consideration it is entitled to in exchange for the goods or services it transfers to the customer.

The promised goods or services in the Company’s arrangements typically consist of a license to the Company’s intellectual property and research and development services. The Company provides options to additional items in such arrangements, which are accounted for as separate contracts when the customer elects to exercise such options, unless the option provides a material right to the customer. Performance obligations are promised goods or services in a contract to transfer a distinct good or service to the customer and are considered distinct when (i) the customer can benefit from the good or service on its own or together with other readily available resources and (ii) the promised good or service is separately identifiable from other promises in the contract. In assessing whether promised goods or services are distinct, the Company considers factors such as the stage of development of the underlying intellectual property, the capabilities of the customer to develop the intellectual property on its own or whether the required expertise is readily available and whether the goods or services are integral or dependent to other goods or services in the contract.

The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration and variable consideration. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of potential payment and the likelihood that the payments will be received. The Company utilizes either the most likely amount method or expected value method to estimate the amount expected to be received based on which method best predicts the amount expected to be received. The amount of variable consideration that is included in the transaction price may be constrained and is included in the transaction price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period.

The Company’s contracts often include development and regulatory milestone payments that are assessed under the most likely amount method and constrained if it is probable that a significant revenue reversal would occur. Due to the uncertainty of research and development and regulatory based milestones that are not within the control of the Company, payment becomes probable upon achievement. At the end of each reporting period, the Company re-evaluates the probability of achievement of such development and clinical milestones and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license and collaboration revenue in the period of adjustment. Any amounts due to the Company but not received as of period-end will be recorded to other current assets.

For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). To date, the Company has not recognized any royalty revenue resulting from any of the Company’s collaboration arrangements.

The Company allocates the transaction price based on the estimated standalone selling price. The Company must develop assumptions that require judgment to determine the stand-alone selling price for each performance obligation identified in the contract. The Company utilizes key assumptions to determine the stand-alone selling price, which may include other comparable transactions, pricing considered in negotiating the transaction and the estimated costs including a reasonable margin. Variable consideration is allocated specifically to one or more performance obligations in a contract when the terms of the variable consideration relate to the satisfaction of the performance obligation and the resulting amounts allocated are consistent with the amounts the Company would expect to receive for the satisfaction of each performance obligation. The consideration allocated to each performance obligation is recognized as revenue when control is transferred for the related goods or services.

Research and Development Expenses

Research and development costs include (i) employee-related expenses, including salaries, benefits, and stock-based compensation expense; (ii) external research and development expenses incurred under arrangements with third parties, such as contract research organization (“CROs”) agreements and consultants; (iii) costs associated with preclinical activities and (iv) lab supplies, lab expenses and an allocation of rent, depreciation, and infrastructure. Costs incurred in connection with research and development activities are expensed as incurred.

Costs are considered incurred based on an evaluation of the progress to completion of specific tasks under each contract using information and data, such as patient enrollment or clinical site activations, provided by the Company’s clinical sites and vendors. These costs consist of direct and indirect costs associated with specific projects, as well as fees paid to various entities that perform certain research on behalf of the Company. Depending upon the timing of payments to the service providers, the Company recognizes prepaid expenses or accrued expenses related to these costs. These accrued or prepaid expenses are based on management’s estimates of the work performed under service agreements, milestones achieved, and experience with similar contracts. Milestone payments under license agreements are accrued, with a corresponding expense being recognized, in the period in which the milestone is determined to be probable of achievement and the related amount is reasonably estimable. The Company monitors each of these factors and adjusts estimates accordingly. The Company has not experienced any material differences between accrued costs and actual costs incurred since its inception.

Asset Acquisitions and Acquired In-Process Research and Development Expense

The Company accounts for acquisitions of assets or a group of assets that do not meet the definition of a business as asset acquisitions based on the cost to acquire the asset or group of assets, which include certain transaction costs. In an asset acquisition, the cost to acquire is allocated to the identifiable assets acquired and liabilities assumed based on their relative fair values as of the acquisition date. No goodwill is recorded in an asset acquisition. Assets that are acquired in an asset acquisition for use in research and development activities that have an alternative future use are capitalized as in process research and development (“IPR&D”). Acquired IPR&D that has no alternative future use as of the acquisition date is recognized as acquired IPR&D expense as of the acquisition date. The Company will recognize additional acquired IPR&D expenses in the future if and when the Company becomes obligated to make contingent milestone payments under the terms of the agreements by which it acquired the IPR&D assets. The Company classifies payments made for the acquisition of IPR&D assets, whether capitalized or expensed, as investing activities on its statement of cash flows.

Contingent consideration in the form of milestone payments related to IPR&D with no alternative future use are charged to expense when the related milestone is achieved and becomes payable. When milestone payments are in the form of equity consideration, the Company evaluates whether the payment should be treated as a liability or

meets the definition of a derivative. When liability or derivative treatment is not required, such milestone payments are recorded at fair value as a component of equity and not remeasured.

For additional information, see Note 8, License Agreements, to these consolidated financial statements.

Comprehensive Loss

Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. Comprehensive loss consists of net loss and other comprehensive loss. During the years ended December 31, 2025 and 2024, the Company’s only element of other comprehensive loss was foreign currency translation adjustments.

Leases

The Company determines if an arrangement is a lease at inception. Operating leases are included in right-of use lease assets (“ROU assets”), current portion of lease obligations and long-term lease obligations on the Company’s consolidated balance sheet. Assets subject to finance leases are included in property and equipment, and the related lease obligation is included in other current liabilities and other long-term liabilities on the Company’s consolidated balance sheet. Lease assets are tested for impairment in the same manner as long-lived assets used in operations. Lease expense for operating leases is recognized on a straight-line basis over the lease term as an operating expense, while expense for financing leases is recognized as depreciation expense (classified as an operating expense) and interest expense (classified as a non-operating expense) using the effective interest method. The Company has elected the short-term lease recognition exemption for short-term leases, which allows the Company not to recognize lease liabilities and ROU assets on the consolidated balance sheet for leases with an original term of twelve months or less.

ROU assets represent the Company’s right to use an underlying asset for the lease term, and lease obligations represent the Company’s obligation to make lease payments arising from the lease. Operating lease liabilities and their corresponding ROU assets are initially recognized based on the present value of lease payments over the expected remaining lease term. When determining the lease term, the Company includes options to extend or terminate the lease when it is reasonably certain that the Company will exercise the option. Certain adjustments to the ROU asset may be required for items such as incentives received from the lessor. The interest rate implicit in lease contracts is typically not readily determinable. Therefore, the Company utilizes its incremental borrowing rate to discount lease payments. The incremental borrowing rate reflects the fixed rate at which the Company could borrow, on a collateralized basis, the amount of the lease payments in the same currency, for a similar term, in a similar economic environment. Prospectively, the Company will adjust the ROU assets for straight-line rent expense, or any incentives received and remeasures the lease liability at the net present value using the same incremental borrowing rate that was in effect as of the lease commencement or transition date. The Company generally accounts for non-lease components together with lease components. The Company expenses variable payments included in a lease arrangement as such expenses are incurred.

For additional information, see Note 6, Leases, to these consolidated financial statements.

Income Taxes

The Company accounts for income taxes in accordance with ASC Topic 740, Accounting for Income Taxes, which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. The Company determines its deferred tax assets and liabilities based on differences between financial reporting and tax bases of assets and liabilities, which are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. Valuation allowances are provided if, based upon the weight of available evidence, it is more likely than not that some or all deferred tax assets will not be realized.

The Company accounts for uncertain tax positions recognized in the consolidated financial statements by prescribing a “more likely than not” threshold for financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. There are no unrecognized tax benefits included in the Company’s consolidated balance sheets as of December 31, 2025 and 2024. The Company’s policy is to recognize interest and penalties related to income tax

matters in income tax expense. The Company has not recognized interest or penalties related to uncertain tax positions in its consolidated statements of operations and comprehensive loss since inception.

Stock-Based Compensation

The Company grants stock-based awards to employees, non-employee consultants and members of its board of directors (the “Board”). Stock-based compensation is recognized as expense for each stock-based award based on its estimated fair value on the date of grant. The Company’s share-based payments include stock options, grants of restricted common stock and restricted stock units (“RSUs”). The value of the award is recognized as expense on a straight-line basis over the requisite service period, and expense is adjusted for pre-vesting forfeitures in the period in which the forfeitures occur. Stock-based compensation expense is classified in the accompanying consolidated statements of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipients service payments are classified.

The Company estimates the fair value of each RSUs at its grant date based on the estimated fair value of the Company’s common stock on that date as determined by the Board. The Company estimates the fair value of stock option awards on the grant date using a Black-Scholes option pricing model. The Company estimates the expected option lives using the simplified method, volatility using historical stock prices of peer companies, the risk-free rates using the U.S Treasury yield curve in effect with a remaining term equal to the expected term and dividend yield based on the Company’s history of paying no dividends and the expectations of paying no cash dividends in the foreseeable future. Prior to the Company’s IPO, the fair value of the Company’s common stock on the date of grant was determined by the Board, taking into consideration its most recently available third-party valuations of common stock as well as additional factors which may have changed since the date of the most recent contemporaneous valuation through the grant date.

For additional information, see Note 11, Stock-Based Compensation, to these consolidated financial statements.

Net Loss Per Share

Basic net loss per share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed using the weighted-average number of common shares outstanding during the period and, if dilutive, the weighted-average number of potential shares of common stock. Net loss per share is calculated using the two- class method, which is an earnings allocation formula that determines net loss per share for the holders of the Company’s common shares and participating securities. The Company’s convertible preferred stock contained participation rights in any dividend paid by the Company and was deemed to be a participating security. Net loss attributable to common stockholders and participating preferred shares are allocated to each share on an as-converted basis as if all of the earnings for the period had been distributed. The participating securities do not include a contractual obligation to share in losses of the Company and are not included in the calculation of net loss per share in the periods in which a net loss is recorded.

Diluted net loss per share is computed using the more dilutive of (a) the two-class method or (b) the if- converted method. The weighted-average number of common shares included in the computation of diluted net loss per share gives effect to all potentially dilutive common equivalent shares, including outstanding stock options and preferred stock.

Common stock equivalent shares are excluded from the computation of diluted net loss per share if their effect is antidilutive. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share is the same as basic net loss since dilutive common shares are not assumed to have been issued if their effect is antidilutive. The Company reported a net loss for the years ended December 31, 2025 and 2024.

Recent Accounting Pronouncements

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740)—Improvements to Income Tax Disclosures (“ASU 2023-09”), which requires a company to expand its existing income tax disclosures, specifically related to the rate reconciliation and income taxes paid. ASU 2023-09 is effective for the Company beginning in fiscal year 2025. This

standard became effective for the Company for the annual reporting period ended December 31, 2025, and was adopted using the prospective method. The adoption of this standard resulted in additional disclosure of the rate reconciliation. The adoption did not have a material impact on the consolidated financial position or results of operations. See Note 13, Income Taxes, to these consolidated financial statements, for our updated income tax presentation.

In November 2024, the FASB issued 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”), which requires entities to disclose additional information about specific expense categories in the notes to the financial statements. ASU 2024-03 is effective annual for periods beginning after December 15, 2026 and for interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. ASU 2024-03 may be applied retrospectively or prospectively to the financial statements. The Company is currently evaluating the impact of ASU 2024-03 on the consolidated financial statements and related disclosures.

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that we adopt as of the specified effective date. Unless otherwise discussed, we do not believe that the adoption of recently issued standards have or may have a material impact on our consolidated financial statements or disclosures.