Monte Rosa Therapeutics, Inc.

1. Description of business and liquidity

Business

Monte Rosa Therapeutics, Inc. is a biotechnology company developing a portfolio of novel small molecule precision medicines that employ the body’s natural mechanisms to selectively degrade therapeutically-relevant proteins. As used in these consolidated financial statements, unless the context otherwise requires, references to the Company or Monte Rosa refer to Monte Rosa Therapeutics, Inc. and its wholly owned subsidiaries Monte Rosa Therapeutics AG and Monte Rosa Therapeutics Securities Corporation. Monte Rosa Therapeutics AG, a Swiss operating company, was incorporated under the laws of Switzerland in April 2018. Monte Rosa Therapeutics, Inc. was incorporated in Delaware in November 2019. The Company is headquartered in Boston, Massachusetts with research operations in both Boston and Basel, Switzerland.

Risks and uncertainties

The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, the successful discovery and development of its product candidates, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing.

Liquidity considerations

Since inception, the Company has devoted substantially all its efforts to business planning, research and development, recruiting management and technical staff, and raising capital and has financed its operations primarily through issuance and sale of convertible promissory notes, convertible preferred stock, public offerings of common stock or warrants to purchase common stock, registered direct offerings, and through its collaborations with F. Hoffman-La Roche Ltd. and Hoffman-La Roche Inc., or Roche, and with Novartis AG, or Novartis.

The Company’s continued discovery and development of its product candidates will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if product development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

As of December 31, 2025, the Company had an accumulated deficit of$477.2 million. The Company has incurred losses and negative cash flows from operations since inception, including net losses of$38.6 million and$72.7 million for the years ended December 31, 2025 and 2024, respectively. The Company expects that its operating losses and negative cash flows will continue for the foreseeable future as the Company continues to develop its product candidates. The Company currently expects that its cash, cash equivalents and marketable securities of$377.1 million as of December 31, 2025, will be sufficient to fund operating expenses and capital requirements for at least 12 months from the date the 2025 annual consolidated financial statements are issued. However, additional funding will be necessary to fund future discovery research, preclinical and clinical activities. The Company will seek additional funding through public financings, debt financings, collaboration agreements, strategic alliances and licensing arrangements. Although it has been successful in raising capital in the past, there is no assurance that the Company will be successful in obtaining such additional financing on terms acceptable to it, if at all, and the Company may not be able to enter into collaborations or other arrangements. If the Company is unable to obtain funding, it could be forced to delay, reduce or eliminate its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect the Company’s business prospects, and even the ability to continue operations.

2. Summary of significant accounting policies

Basis of presentation

Theaccompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America, or GAAP, and are stated in U.S. dollars. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting

Standards Codification and Accounting Standards Updates, or ASUs, of the Financial Accounting Standards Board, or FASB. All intercompany balances and transactions have been eliminated in consolidation.

Use of estimates

The preparation of the consolidated financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the consolidated financial statements and reported amounts of expenses during the reporting periods. Actual results could differ from those estimates. On an ongoing basis, the Company evaluates its estimates, including those related to revenue recognition, accrued research and development expenses, pension benefit obligation, stock-based compensation and the valuation of deferred tax assets. The Company bases its estimates using historical experience, Company forecasts and future plans, current economic conditions, and information from third-party professionals that management believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities and recorded amounts of expenses that are not readily apparent from other sources and adjusts those estimates and assumptions when facts and circumstances dictate.

Currency and currency translation

The consolidated financial statements are presented in U.S. dollars, the Company’s reporting currency. The functional currency of the Company’s wholly owned subsidiaries, Monte Rosa Therapeutics AG and Monte Rosa Securities Corporation, is the U.S. dollar. Adjustments that arise from exchange rate changes on transactions denominated in a currency other than the functional currency are included in foreign currency exchange gain (loss), net in the consolidated statements of operations.

Cash, cash equivalents and restricted cash

The Company considers all highly liquid investments with original maturities at the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents are stated at fair value and may include money market funds, U.S. Treasury and U.S. government-sponsored agency securities, corporate debt, commercial paper and certificates of deposit. The Company’s cash equivalents at December 31, 2025 and 2024 consist of bank demand deposits and money market fund investments.

The Company had restricted cash of$5.0 million and$4.9 million as of December 31, 2025 and 2024, respectively, primarily related to security deposits on its leases for offices in Boston, Massachusetts and Basel, Switzerland.

Marketable securities

Investments in marketable securities are classified as available-for-sale. Available-for-sale securities are measured and reported at fair value using quoted prices in active markets for similar securities. Unrealized gains and losses on available-for-sale securities are reported as a separate component of stockholders’ equity. Premiums or discounts from par value are amortized to investment income over the life of the underlying investment. All of the Company’s available-for-sale securities are available to the Company for use in current operations. As a result, the Company classified all of these securities as current assets even though the stated maturity of some individual securities may be one year or more beyond the balance sheet date.

The Company reviews marketable securities whenever the fair value of an investment is less than the amortized cost and evidence indicates that an investment’s carrying value is not recoverable. For available-for-sale debt securities, the credit allowance is limited to the amount that fair value is less than amortized cost. Unrealized gains (losses) are evaluated for impairment under ASC 326, Financial Instruments - Credit Losses, to determine if the impairment is credit-related or noncredit-related. Credit-related impairment is recognized as an allowance on the consolidated balance sheets with a corresponding adjustment to earnings, and noncredit-related impairment is recognized in other comprehensive loss. Evidence considered in this assessment includes reasons for the impairment, compliance with our investment policy, the severity of the impairment, collectability of the security, and any adverse conditions specifically related to the security, an industry, or geographic area. No such adjustments were necessary during the periods presented.

Concentrations of credit risk and off-balance sheet risk

Financial instruments that potentially subject the Company to a concentration of credit risk consist primarily of cash, cash equivalents, and marketable securities. The Company has invested in cash and cash equivalents at December 31, 2025 and 2024, held in financial institutions that management believes are creditworthy. These deposits may exceed federally insured limits. The Company has not experienced any losses historically in these accountsand believes it is not exposed to significant credit risk in its cash and cash equivalents. The Company has no significant off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts, or other hedging arrangements.

Fair value of financial instruments

Assets and liabilities recorded at fair value on a recurring basis in the balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows:

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

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

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

To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in 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 instrument.

Property and equipment

Property and equipment are stated at cost, subject to adjustments for impairments, less accumulated depreciation. Purchased assets that are not yet in service are classified as construction-in-process and no depreciation expense is recorded. Depreciation is calculated using the straight-line method over the estimated useful life of the asset as follows:

Maintenance and repairs that do not improve or extend the life of the respective asset are expensed as incurred. Upon disposal of an asset, the related cost and accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the results of operations. Leasehold improvements are amortized over the shorter of the useful life or remaining term of the lease.

Impairment of long-lived assets

The Company evaluates whether current facts or circumstances indicate that the carrying values of its long-lived assets may not be recoverable. If such facts or circumstances are determined to exist, an estimate of the undiscounted future cash flows of these assets is compared to the carrying value the assets to determine whether impairment exists. If the assets are determined to be impaired, the loss is measured based on the difference between the fair value and carrying value of the assets. No material impairment losses were recorded during the periods presented.

Research and development costs are expensed as incurred. The Company’s research and development expenses consist primarily of costs incurred for the research and development of its product candidates and include expenses incurred under agreements with consultants to conduct preclinical and clinical studies, costs to acquire supplies for preclinical and clinical studies, salaries and related personnel costs, including stock-based compensation, depreciation and other allocated facility-related and overhead expenses.

Accrued research and development costs

The Company records accruals for estimated costs of discovery research activities, preclinical, and clinical studies. A portion of the Company’s research and development activities are conducted by third-party service providers. The financial terms of these contracts are subject to negotiation, which vary by contract and may result in payments that do not match the periods over which materials or services are provided. The Company accrues the costs incurred under the agreements based on an estimate of actual work completed in accordance with the agreements. In the event the Company makes advance payments for goods or services that will be used or rendered for future research and development activities, the payments are deferred and capitalized as a prepaid expense and recognized as expense as the goods are received or the related services are rendered. Such payments are evaluated for current or long-term classification based on when they are expected to be realized. If the Company does not identify costs that have begun to be incurred or if the Company underestimates or overestimates the level of services performed or the costs of these services, actual expenses could differ from the Company’s estimates.

Stock-based compensation

Stock-based compensation expense related to stock options granted to employees, directors and non-employees is recognized based on the grant-date estimated fair values of the awards using the Black-Scholes option pricing model, or Black-Scholes. Stock-based compensation expense related to stock options and other stock based awards granted to employees and non-employees is recognized based on the grant-date fair value of the Company’s common stock. The value is recognized as expense ratably over the requisite service period, which is generally the vesting term of the award. For stock options with performance-based vesting conditions, the Company records the expense for these awards based upon the fair value of the awards on the date of grant and the number of shares expected to vest based on the terms of the underlying award agreement and the requisite service periods. The Company adjusts the expense for actual forfeitures as they occur. Stock-based compensation expense is classified in the accompanying consolidated statements of operations based on the function to which the related services are provided.

Income taxes

The Company uses the liability method to account for income taxes. Under this method, deferred tax assets and liabilities are determined based on differences between the financial statement carrying amounts of existing assets and liabilities and their tax bases. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. A valuation allowance is established when necessary to reduce deferred tax assets to the amount expected to be realized.

The Company assesses the likelihood of deferred tax assets being realized. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. In assessing the realizability of deferred tax assets, the Company considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which the temporary differences representing net future deductible amounts become deductible.

The Company files U.S. federal and state income tax returns, as well as Swiss income tax returns. The Company’s tax positions are subject to audit. Financial statement effects of uncertain tax positions are recognized when it is more likely than not, based on the technical merits of the position, that it will be sustained upon examination. The Company evaluates uncertain tax positions on a regular basis. The evaluations are based on a number of factors, including changes in facts and circumstances, changes in tax law, correspondence with tax authorities during the course of the audit, and effective settlement of audit issues. Interest and penalties related to unrecognized tax benefits are included within the provision for income tax. To date, the Company has not been subject to any interest and penalties.

Defined pension benefit obligation

The Company maintains a mandatory pension for its employees in Switzerland through affiliation with the AXA Leben AG, or AXA. All benefits in accordance with the regulations are reinsured in their entirety with AXA within the framework of the corresponding contract. This plan is considered to be a defined benefit plan under GAAP.

The Company recognizes an asset for the plan’s overfunded status or a liability for the plan’s underfunded status on its consolidated balance sheets. Additionally, the Company measures the plan’s assets and obligations that determine its funded status as of the end of the year and recognizes the change in the funded status within the consolidated statements of operations and comprehensive loss.

The Company uses an actuarial valuation to determine its pension benefit costs and credits. The amounts calculated depend on a variety of key assumptions, including discount rates and expected return on plan assets. Details of the assumptions used to determine the net funded status are described in Note 13, Employee retirement plans. The Company’s pension plan assets are assigned to their respective levels in the fair value hierarchy in accordance with the valuation principles described in the Fair Value of Financial Instruments section above.

Segments

Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the chief operating decision maker, or CODM, in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s CODM is its chief executive officer. The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions.

Revenue recognition

The Company recognizes revenue in accordance with ASC No. 606, Revenue from Contracts with Customers, or ASC 606. ASC 606 applies to all contracts with customers, except for certain contracts that are within the scope of other guidance. Accordingly, the Company recognizes revenue when its customer obtains control of the promised goods and/or services in an amount that reflects the consideration it expects to receive in exchange for those goods and/or services. To determine the appropriate amount of revenue to be recognized, the Company performs the following steps: (i) Identify the contract(s) with the customer, (ii) Identify the promised goods and/or services in the contract and determine which promised goods and/or services represent performance obligations, (iii) Measure the transaction price, (iv) Allocate the transaction price to the performance obligations in the contract and (v) Recognize revenue when (or as) each performance obligation is satisfied.

Pursuant to the guidance in ASC 606, the Company accounts for a contract with a customer that is within the scope of ASC 606 when all of the following criteria are met: (i) The arrangement has been approved by the parties and the parties are committed to perform their respective obligations, (ii) Each party’s rights regarding the goods and/or services to be transferred can be identified, (iii) The payment terms for the goods and/or services to be transferred can be identified, (iv) The arrangement has commercial substance and (v) Collection of substantially all of the consideration to which the Company will be entitled in exchange for the goods and/or services that will be transferred to the customer is probable.

The Company assesses the goods and/or services promised within a contract that contains multiple promises to evaluate which promises are distinct. Promises are considered to be distinct and therefore, accounted for as separate performance obligations, provided that: (i) The customer can benefit from the good or service either on its own or together with other resources that are readily available to the customer and (ii) The promise to transfer the good or service to the customer is separately identifiable from other promises in the contract. The Company determines that a customer can benefit from a good or service if it could be used, consumed, or sold for an amount that is greater than scrap value, or otherwise held in a way that generates economic benefits. Factors that are considered in determining whether or not two or more promises are not separately identifiable include, but are not limited to, the following: (i) The Company provides a significant service of integrating goods and/or services with other goods and/or services promised in the contract, (ii) One or more of the goods and/or services significantly modifies or customizes, or are significantly modified or customized by, one or more of the other goods and/or services promised in the contract and (iii) The goods and/or services are highly interdependent or highly interrelated. In assessing whether promised goods and/or services are distinct from the other promises, the Company considers factors such as the stage of development of the underlying intellectual property, the capabilities of the collaborative partner and the availability of the associated expertise in the marketplace. The Company also considers whether the customer can benefit from a promise for its intended purpose without the receipt of the remaining promises, whether the value of a promise is dependent on the unsatisfied promises, whether there are other vendors that could provide the remaining promises and whether a promise is separately identifiable from the remaining promises. Individual goods or services (or bundles of goods and/or services) that meet both criteria for being distinct are accounted for as separate performance obligations. Promises that are not distinct at contract inception are combined into a single performance obligation.

The Company considers a customer’s right to elect to obtain additional goods and/or services at such customer’s discretion to be an option if it is not presently obligated to provide the goods and/or services and it is not entitled to compensation in exchange for the associated goods and/or services. Options to acquire additional goods and/or services are evaluated to determine if the option provides a material right to the customer that it would not have received without entering into the contract. If so, the option is accounted for as a separate performance obligation. If not, the option is considered a marketing offer which would be accounted for as a separate contract upon the customer’s exercise. Situations in which a customer has an ability to acquire additional goods and/or services for free or at significantly discounted rates are considered to provide the customer with a material right. Options to purchase goods and/or services at prices that reflect the standalone selling prices of the associated goods and/or services are accounted for as marketing offers.

The Company measures the transaction price based on the amount of consideration to which it expects to be entitled in exchange for transferring the promised goods and/or services to the customer. The Company utilizes either the expected value method or the most likely amount method to estimate the amount of variable consideration, depending on which method is expected to better predict the amount of consideration to which it will be entitled. Amounts of variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. With respect to research, development, regulatory and first sale milestone payments, at the inception of the arrangement, the Company evaluates whether the associated event is considered probable of achievement and estimates the amount to be included in the transaction price using the most likely amount method. As part of the evaluation for research and development milestone payments, the Company considers several factors, including the stage of development of the targets included in the arrangement, the risk associated with the remaining research and development work required to achieve the particular milestone and whether or not the achievement of the specific milestone event is within the Company’s control. Milestone events that are not within the control of the Company or the licensee, such as those dependent upon receipt of regulatory approval or the first sale of a commercialized product, are not considered to be probable of achievement until the triggering event occurs. With respect to royalties, including milestone payments based upon the achievement of a certain level of product sales, wherein the license is deemed to be the sole or predominant item to which the payments relate, the Company recognizes revenue upon the later of: (i) When the related sales occur or (ii) When the performance obligation to which some or all of the payment has been allocated has been satisfied (or partially satisfied). To date, the Company has not recognized any regulatory or sales-based milestone payments or royalty revenue resulting from its collaboration arrangements.

The Company updates its assessment of the estimated transaction price, including the constraint on variable consideration, at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur. Any adjustments to the transaction price are recorded on a cumulative catch-up basis, which affect revenue and net loss in the period of adjustment. Amounts to be received with respect to customer options are included in the transaction price upon exercise. And payments associated with milestone events that may only be achieved after the exercise of a customer option are excluded from the initial determination of the transaction price.

The Company generally allocates the transaction price to each performance obligation identified in the contract on a relative standalone selling price basis. However, certain components of variable consideration are allocated specifically to one or more particular performance obligations to the extent both of the following criteria are met: (i) The terms of the payment relate specifically to the efforts to satisfy the performance obligation or transfer the distinct good or service and (ii) Allocating the variable amount of consideration entirely to the performance obligation or the distinct good or service is consistent with the allocation objective of the standard whereby the amount allocated depicts the amount of consideration to which the entity expects to be entitled in exchange for transferring the promised goods or services. Option exercise fees are allocated to the goods and/or services underlying the associated option. The Company develops assumptions that require judgment to determine the standalone selling price for each performance obligation identified in the contract. The key assumptions utilized in determining the standalone selling price for each performance obligation include projected development timelines, estimated research costs, likelihood of exercise and probabilities of technical success.

Revenue is recognized based on the amount of the transaction price that is allocated to each respective performance obligation when or as the performance obligation is satisfied by transferring a promised good and/or service to the customer. For performance obligations that are satisfied at a point in time, the Company recognizes revenue when control of the goods and/or services are transferred to the customer. For performance obligations that are satisfied over time, the Company recognizes revenue by measuring the progress toward complete satisfaction of the performance obligation using a single method of measuring progress which depicts the performance in transferring control of the associated goods and/or services to the customer. The Company uses input methods to measure the progress toward the complete satisfaction of performance obligations satisfied over time. With respect to promises related to licenses to intellectual property that is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenue from amounts allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. Any such adjustments are recorded on a cumulative catch-up basis, which affect revenue and net loss in the period of adjustment. Amounts allocated to material rights are recognized as revenue the earlier of: (i) When or as the option is exercised and the underlying future goods and/or services are transferred or (ii) When the option expires.

Significant judgments and estimates made in accounting for contracts with customers include: identifying the performance obligations in the contract, measuring the amount of variable consideration to include in the transaction price, estimating the standalone selling prices of the individual performance obligations, assessing the nature of a combined performance obligation to determine whether control is transferred over time or at a point in time, selecting the appropriate method of measuring progress used to recognize revenue for performance obligations satisfied over time and updating measures of progress to reflect revisions in the outcome of performance obligations. Certain of these judgments and estimates are subject to change over the course of the arrangement, particularly with respect to estimating variable consideration and updating the measure of progress, which would impact the revenue recognized. Significant changes in these assumptions and estimates could have a material impact on the timing and amount of revenue recognized in future periods. The Company considers at the contract level whether there is a need for a provision for losses on contracts.

The Company receives payments from its licensee based on billing schedules established in the contract. Amounts received or due prior to the Company performing its obligations under the arrangement are recorded as deferred revenue. Amounts expected to be recognized as revenue within the 12 months following the balance sheet date are classified as current deferred revenue. Amounts not expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue, net of current portion. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to the consideration is unconditional.

Warrants

The Company accounts for common stock warrants as either equity-classified or liability-classified instruments based on an assessment of the warrant’s specific terms and applicable authoritative guidance in ASC No. 480, Distinguishing Liabilities from Equity, or ASC 480, and ASC No. 815, Derivatives and Hedging, or ASC 815. The assessment considers whether the warrants are freestanding financial instruments pursuant to ASC 480, whether the warrants meet the definition of a liability pursuant to ASC 480, and whether the warrants meet all of the requirements for equity classification under ASC 815, including whether the warrants are indexed to the Company’s own common stock and whether the warrant holders could potentially require “net cash settlement” in a circumstance outside of the Company’s control, among other conditions for equity classification. This assessment, which requires the use of professional judgment, is conducted at the time of warrant issuance and as of each subsequent quarterly period end date while the warrants are outstanding.

For issued or modified warrants that meet all of the criteria for equity classification, the warrants are required to be recorded as a component of additional paid-in capital at the time of issuance. For issued or modified warrants that do not meet all the criteria for equity classification, the warrants are required to be recorded at their initial fair value on the date of issuance and remeasured each balance sheet date thereafter. Changes in the estimated fair value of the liability-classified warrants are recognized as a non-cash gain or loss in the accompanying consolidated statements of operations and comprehensive loss.

Comprehensive income (loss)

Comprehensive income (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. The Company’s other comprehensive income (loss) includes adjustments to unrecognized pension benefit costs for Monte Rosa Therapeutics AG and changes in unrealized gains and losses from available-for-sale investments. The Company reported other comprehensive loss of$0.5 million and$0.6 million for the years ended December 31, 2025 and 2024, respectively.

Recently issued accounting pronouncements

The Company has elected to use the extended transition period for complying with new or revised accounting standards as available under the Jumpstart Our Business Startups Act (JOBS Act).

In November 2024, the FASB issued ASU 2024-03, Income Statement Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40), which requires disaggregated disclosure of income statement expenses for public business entities. ASU 2024-03 requires disclosure of, in a tabular presentation, each relevant expense caption on the face of the income statement that includes any of the following natural expenses: (1) purchases of inventory, (2) employee compensation, (3) depreciation, (4) intangible asset amortization, and (5) depreciation, depletion, and amortization (DD&A) recognized as part of oil- and gas-producing activities or other types of depletion expenses. The tabular disclosure would also include certain other expenses, when applicable. The standard is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. The Company is currently evaluating the impact the adoption of this standard will have on its consolidated financial statements and related disclosures.

Recently adopted accounting pronouncements

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which is intended to provide enhancements to annual income tax disclosures. The standard requires more detailed information in the rate reconciliation table and for income taxes paid, among other enhancements. The Company retroactively adopted ASU 2023-09 in December 2025 and updated its disclosures in Note 12, Income taxes, as a result. The adoption did not otherwise materially affect the Company's consolidated financial statements.

3. Fair value measurements

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

Money market funds are highly liquid investments and are actively traded. The pricing information on the Company’s money market funds is based on quoted prices in active markets for identical securities. This approach results in the classification of these securities as Level 1 of the fair value hierarchy.

The fair value of pension plan assets has been determined as the surrender value of the portfolio of active insured members held within the Columna Collective Foundation Group investment fund and is classified within Level 2 of the fair value hierarchy.

Marketable securities consist of corporate debt securities and U.S. Treasury securities which are classified as available-for-sale pursuant to ASC 320, Investments—Debt and Equity Securities. Marketable securities are classified within Level 2 of the fair value hierarchy because pricing inputs are other than quoted prices in active markets. The fair values of these investments are estimated by taking into consideration valuations obtained from third-party pricing services. The pricing services utilize industry standard valuation models, including both income- and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities, issuer credit spreads, benchmark securities based on historical data and other observable inputs.

There wereno transfers among Level 1, Level 2 or Level 3 categories in the years ended December 31, 2025 and 2024.

4. Marketable securities

Marketable securities as of December 31, 2025, consisted of the following (in thousands):

Marketable securities as of December 31, 2024, consisted of the following (in thousands):

As of December 31, 2025, the Company held 69 marketable securities, 1 of which was in an unrealized loss position, and the aggregate fair value of securities in a loss position was$3.2 million. As of December 31, 2024, the Company held 53 marketable securities, 9 of which were in an unrealized loss position, and the aggregate fair value of securities in a loss position was$20.0 million. There wereno individual securities that were in a significant unrealized loss position as of December 31, 2025 or 2024.

The Company holds debt securities of companies with high credit quality and has determined that there was no material change in the credit risk of any of its debt securities. The Company also believes that it will be able to collect both principal and interest amounts due to it at maturity.

5. Property and equipment, net

Property and equipment, net, consist of the following (in thousands):

Depreciation expense for the years ended December 31, 2025 and 2024 was$8.4 million and$8.1 million, respectively.

6. Accrued expenses and other current liabilities

Accrued expenses and other current liabilities consist of the following (in thousands):

7. Leases

The Company determines if an arrangement is a lease at inception. Operating leases are included in operating lease right-of-use or ROU assets and operating lease liabilities in the consolidated balance sheets. The Company hasno finance leases as of December 31, 2025.

ROU assets represent the right to use an underlying asset for the lease term and lease liabilities represent the 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. As the Company’s leases do not provide an implicit rate, management estimated the incremental borrowing rate based on the rate of interest the Company would have to pay to borrow a similar amount on a collateralized basis over a similar term. The Company uses its incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments.

Klybeckstrasse Lease

In March 2021, the Company entered into an operating lease agreement, or the Klybeckstrasse Lease, for office and laboratory space with Wincasa AG, or the Basel Landlord, that occupies approximately 21,422 square feet located at Klybeckstrasse 191, 4057 Basel, Basel-City, Switzerland. In April 2023, the Company and the Basel Landlord amended the Klybeckstrasse Lease which increased the office and laboratory space square footage from 21,422 square feet to 44,685 square feet and extended the term of the lease through June 30, 2027.

Harrison Avenue Lease

In December 2021, the Company entered into a non-cancelable lease agreement, or the Harrison Avenue Lease, for 63,327 square feet of office and laboratory space to support its expanding operations, or the Harrison Avenue Lease. The term of the lease commenced on April 1, 2022, and the Company’s obligation to pay rent began on December 21, 2022. The initial term of the lease is 128 months following the commencement date at which point the Company has the option to extend the lease an additional 5 years. The Company has determined that it is not reasonably certain to exercise the option to extend the lease and has not included the extension period in the lease term. The annual base rent under the Harrison Avenue Lease is $95 per square foot for the first year, which is subject to scheduled annual increases of 3%, plus certain costs, operating expenses and property management fees.

The components of lease expense for the years ended December 31, 2025 and 2024 are as follows (in thousands):

The variable lease expenses generally include common area maintenance and property taxes.

Of the total lease expense recorded in the consolidated statements of operations and comprehensive loss,$7.8 million and$8.7 million were recorded within research and development expenses and$1.4 million and$1.8 million were recorded in general and administrative expenses for the years ended December 31, 2025 and 2024, respectively. Short-term lease costs in the years ended December 31, 2025 and 2024 were immaterial.

The weighted average remaining lease term and discount rate related to the Company's leases are as follows:

Supplemental cash flow information and other information relating to the Company's leases for the years ended December 31, 2025 and 2024 are as follows (in thousands):

The amortization of the ROU assets for the years ended December 31, 2025 and 2024 was$2.5 million and$2.1 million, respectively.

Future minimum lease payments under non-cancelable leases as of December 31, 2025 for each of the years ending December 31 st are as follows (in thousands):

8. Commitments and contingencies

Legal proceedings

From time to time, the Company may be subject to legal proceedings, claims and disputes that arise in the ordinary course of business. The Company accrues a liability for such matters when it is probable that future expenditures will be made and that such expenditures can be reasonably estimated. As of December 31, 2025, the Company is not a party to any litigation and does not have a contingency reserve established for any litigation liabilities.

Indemnification

The Company, as permitted under Delaware law and in accordance with its certification of incorporation and bylaws and pursuant to indemnification agreements with certain of its officers and directors, indemnifies its officers and directors for certain events or occurrences, subject to certain limits, which the officer or director is or was serving at the Company’s request in such capacity.

The Company enters into certain types of contracts that contingently require the Company to indemnify various parties against claims from third parties. These contracts primarily relate to (i) the Company’s bylaws, under which the Company must indemnify directors and executive officers, and may indemnify other officers and employees, for liabilities arising out of their relationship, (ii) contracts under which the Company must indemnify directors and certain officers and consultants for liabilities arising out of their relationship, and (iii) procurement, service or license agreements under which the Company may be required to indemnify vendors, service providers or licensees for certain claims, including claims that may be brought against them arising from the Company’s acts or omissions with respect to the Company’s products, technology, intellectual property or services.

From time to time, the Company may receive indemnification claims under these contracts in the normal course of business. In the event that one or more of these matters were to result in a claim against the Company, an adverse outcome, including a judgment or settlement, may cause a material adverse effect on the Company’s future business, operating results or financial condition. As of December 31, 2025 and 2024, the Company was not aware of any claims under indemnification arrangements and does not expect significant claims related to these indemnification obligations and, consequently, concluded that the fair value of these obligations is negligible. Therefore, no related reserves have been established.

9. Collaboration and license agreements

In October 2023, Monte Rosa Therapeutics AG, a wholly-owned subsidiary of Monte Rosa Therapeutics, Inc, or the Company, entered into a collaboration and license agreement, or the Roche Agreement, with Roche. Pursuant to the Roche Agreement, the parties will seek to identify and develop molecular glue degraders, or MGDs, against cancer or neurological disease targets using the Company’s proprietary drug discovery engine for an initial set of targets in oncology and neuroscience selected by Roche, wherein a certain number of targets selected by Roche are for a limited time subject to replacement rights owned by Roche. The Company will lead preclinical discovery and research activities with Roche leading late preclinical and clinical development activities.

Under the Roche Agreement, Roche will have a worldwide, exclusive license under patents and know-how controlled by the Company to develop and commercialize products directed to applicable targets. The license exclusivity is subject to the Company’s retained rights solely to fulfill its obligations under the arrangement.

The research collaboration activities governed by the Roche Agreement are overseen by a joint research committee.

Unless earlier terminated, the Roche Agreement will remain in effect for each product licensed under the Roche Agreement until expiration of the royalty term for the applicable product. The parties have included termination provisions in the Roche Agreement, allowing termination of the Roche Agreement in its entirety, on a country-by-country or a target-by-target basis.

Pricing

In November 2023, the Company received a $50.0 million non-refundable upfront payment for the initial set of targets. Pursuant to the terms of the Roche Agreement, the Company expects to be entitled to receive from Roche certain variable consideration including potential preclinical milestones up to $172 million, and potential clinical, commercial and sales milestones exceeding $2 billion. The Company is also eligible to receive tiered royalties ranging from high-single-digits to low-teens on any products that are commercialized by Roche as a result of the collaboration.

To date through December 31, 2025, the Company has received$9.0 million and recorded a$7.0 million receivable related to Roche's decision to pay preclinical milestones. The Company has also received $3.0 million related to Roche's decision to exercise its option rights to replace certain targets for research and development services. The related payments are initially classified as deferred revenue in the accompanying consolidated balance sheet and recognized in revenue as the related research and development services are performed.

This agreement represents a transaction with a customer and therefore is accounted for under ASC 606, Revenue From Contracts With Customers.

The Company determined that the development and commercialization licenses for each of the collaboration targets is neither capable of being distinct nor distinct within the context from the promised initial research services. In addition, the Company has determined that each target in the agreement is distinct from other targets because: (i) Roche can benefit from the license and research services for a given target on their own since the results related thereto can be evaluated discretely and (ii) the results of the research and development of each target does not affect either the Company’s ability to perform or Roche’s ability to assess the results for any other target. As such, the Company has identified certain performance obligations within the agreement as follows:

•

Performance obligations for the research and development of initial targets, and

•

Performance obligations for the research and development services related to Roche’s option to replace certain targets

The total transaction price of the Roche Agreement is allocated to the performance obligations based on their relative standalone selling price. The Company developed the standalone selling price for the performance obligations included in the Roche Agreement by determining the total estimated costs to fulfill each performance obligation identified with the objective of determining the price at which it would sell such an item if it were to be sold regularly on a standalone basis. The allocated transaction price is recognized as revenue from collaboration agreements in one of two ways:

•

Research and development of the initial targets: The Company recognizes the portion of the transaction price allocated to each of the research and development performance obligations as the research and development services are provided, using an input method, in proportion to costs incurred to date for each research development target as compared to total costs incurred and expected to be incurred in the future to satisfy the underlying obligation related to said research and development target. The transfer of control occurs over this period and, in management’s judgment, is the best measure of progress towards satisfying the performance obligation.

•

Option rights to replace targets: The transaction price allocated to the replacement option rights, which are considered material rights, is deferred until the period that Roche elects to exercise or elects to not exercise its option right to license and commercialize the underlying research and development target. Upon Roche's exercise of a replacement option right, the Company will recognize the portion of the transaction price allocated using the input method described above. Any payments made to exercise replacement option rights will be added to the allocated value and recognized as the related services are performed.

To date through December 31, 2025,$46.3 million related to the Roche Agreement has been recognized as collaboration revenue in the consolidated statements of operations and comprehensive loss. The remaining$22.7 million of the upfront payment and subsequent milestone and replacement target payments related to customer options are recorded as deferred revenue in the liabilities section of the consolidated balance sheet, with$10.6 million included in current liabilities and$12.1 million included in non-current liabilities.

The following table summarizes the deferred revenue amounts allocated to the Roche Agreement performance obligations (in thousands):

The Company expects that the remaining deferred revenue for the initial targets will be recognized within 21 months. The Company expects that deferred revenue related to replacement targets will be recognized within 33 months. Due to the uncertain nature of the research and development being performed by the Company, it may take longer than anticipated to recognize revenue related to the performance obligations for the initial and replacement targets. Any amounts remaining in deferred revenue will be recognized at the conclusion of the Roche Agreement in October 2028.

As of December 31, 2025, potential research, development and regulatory milestone payments that the Company is eligible to receive were excluded from the transaction price as they were fully constrained by uncertain events. The Company will reevaluate the transaction price at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur, and if necessary, the Company will adjust its estimate of the transaction price. Any additions to the transaction price would be reflected in the period as a cumulative revenue catch-up based on the ratio of costs incurred to the total estimated costs expected applied to the revised transaction price. Sales-based royalties and milestone payments, which predominantly relate to the license, will be recognized if and when the related sales occur.

2024 Novartis License Agreement

In October 2024, Monte Rosa Therapeutics AG, a wholly-owned subsidiary of the Company, entered into a license agreement with Novartis, or the 2024 Novartis Agreement. Pursuant to the 2024 Novartis Agreement, the Company granted to Novartis an exclusive, royalty-bearing, sublicensable and transferable license to develop, manufacture, and commercialize VAV1 MGDs, including MRT-6160, which is currently in Phase 1 clinical development for immune-mediated conditions. The Company was responsible for completing the Phase 1 clinical study and Novartis is responsible for all subsequent development and commercial activities starting at Phase 2.

Pricing

In December 2024, the Company received a $150 million non-refundable upfront payment. Pursuant to the 2024 Novartis Agreement, the Company is entitled to receive from Novartis up to $2.1 billion in development, regulatory, and sales milestones, beginning upon initiation of Phase 2 studies including (a) potential development and regulatory milestone payments, exceeding $1.5 billionif multiple indications achieve regulatory approval in multiple territories, (b) potential sales milestone payments in connection with sales outside of the U.S., and tiered royalties on sales outside of the U.S. Novartis will be responsible for costs associated with Phase 2 clinical studies. The Company and Novartis also agreed to a net profit and loss sharing arrangement, pursuant to which the Company could co-fund any global clinical development from Phase 3 onwards and will share 30% of any profits and losses associated with the manufacturing and commercialization of the licensed products in the U.S. The Company has defined opportunities to opt out of the net profit and loss sharing arrangement prior to the initiation of Phase 3 clinical trials, in such case, sales in the U.S. would be entitled to the potential sales milestone payments and tiered royalties as sales outside of the U.S. Any costs for any co-funded development and commercialization activities are subject to budgets reviewed by the Company and Novartis.

The goods and services that the Company was obligated to deliver and perform (the License and Licensor Clinical Trial) were accounted for under ASC 606 as they represented a transaction with a customer.

The Company has concluded that the License and the completion of the Licensor Clinical Trial promises are treated as a single, combined performance obligation. The Company has determined the total transaction price to be $150 million, which consists solely of the upfront payment. All milestone payments were constrained as the achievement of the milestones are contingent upon the success of the underlying research and development activities and are generally outside the control of the Company. The Company’s options to share in further development and commercialization efforts via its opt-in/opt-out rights will be assessed and accounted for as separate units of accounting under the relevant guidance if, and when, such options are exercised by the Company.

The revenue the Company recognized associated with the combined performance obligation was recognized over time using a cost-based input methodology. The transfer of control occurred over the course of the Licensor Clinical Trial promise and, in management’s judgment, was the best measure of progress towards satisfying the combined performance obligation.

As of December 31, 2025, the total transaction price of $150 million plus $1.2 million of incremental cost reimbursements related to the Novartis Agreement, has been recognized as collaboration revenuein the consolidated statements of operations and comprehensive loss.

In September 2025, Monte Rosa Therapeutics AG, a wholly-owned subsidiary of the Company, entered into a collaboration, option, and license agreement with Novartis, or the 2025 Novartis Agreement. Pursuant to the 2025 Novartis Agreement, the Company granted to Novartis an exclusive, royalty-bearing, sublicensable and transferable license to degraders for one immunology and inflammation, or I&I program, or the First Licensed Program, and the option to obtain exclusive, royalty-bearing, sublicensable and transferable licenses with respect to two additional programs from the Company’s growing preclinical immunology portfolio, or the Options, and the programs, or the Optioned I&I Programs. Such Options are individually exercisable at Novartis’ discretion until a program meets criteria for investigational new drug application-filing-readiness. On a program-by-program basis, if Novartis does not exercise an Option, all rights with respect to such program are retained by the Company; if Novartis does exercise its Option, such program becomes a Licensed Program, or together, with the First Licensed Program, the Licensed Programs. Under the 2025 Novartis Agreement, the Company will apply its proprietary AI/ML-enabled QuEEN™ engine for the discovery and development of degraders for the First Licensed Program and the Optioned I&I Programs. The Licensed Programs will be further developed and commercialized by Novartis, unless otherwise agreed to by the parties in accordance with the 2025 Novartis Agreement. Research activities for the Licensed Programs governed by the Agreement will be overseen by a Joint Research Committee.

Pricing

In September 2025, the Company received a $120.0 million non-refundable upfront payment from Novartis. Pursuant to the 2025 Novartis Agreement, the Company is entitled to receive from Novartis payments to maintain the Options totaling up to $60.0 million, and is eligible to receive from Novartis (1) preclinical milestone payments relating to the First Licensed Program and option exercise payments related to the Options of up to $180.0 million, (2) up to $5.4 billion in clinical development, regulatory, and sales milestones relating to the First Licensed Program and the two Optioned I&I Programs, beginning upon initiation of Phase 1 studies, including (a) potential development and regulatory milestone payments up to $2.2 billionif regulatory approval is achieved for multiple indicationsin multiple territories and (b) potential sales milestone payments up to $3.2 billion, allocated across licensed products, and (3) tiered royalties on global net sales in the high-single to low double-digit range for the First Licensed Program and in the low double-digit range for the two Optioned I&I Programs. The Company will be responsible for costs related to research activities, while Novartis will be responsible for costs related to development and commercialization activities.

The goods and services that the Company is obligated to deliver and perform under the 2025 Novartis Agreement will be accounted for under ASC 606 as they represent a transaction with a customer.

The Company has concluded that the transaction price at inception is $180 million, which consists of the $120 million upfront payment and $60 million of option maintenance payments due over the course of the contract term. The Company has identified the following performance obligations in the contract:

•

License and research services for an immunology target

•

Research services for certain immunology targets to support the Immunology License Options

•

Material Right First Immunology License Option

•

Material Right Second Immunology License Option

The total transaction price of the 2025 Novartis Agreement is allocated to the performance obligations based on their relative standalone selling prices, or the price at which it would sell such an item if it were to be sold regularly on a standalone basis. The standalone selling price of performance obligations related to license and research services were determined using a cost-plus margin approach. The standalone selling price related to material rights for immunology license options were determined by benchmarking to comparable transactions, probability adjusted for the likelihood of exercise.

The allocated transaction price is recognized as revenue from collaboration agreements in one of two ways:

•

License and research services for immunology targets: The Company recognizes the portion of the transaction price allocated to each of the research performance obligations as the research services are provided, using an input method, in proportion to costs incurred to date for each research development target as compared to total costs incurred and expected to be incurred in the future to satisfy the underlying obligation related to said research services. The transfer of control occurs over this period and, in management’s judgment, is the best measure of progress towards satisfying the performance obligation.

•

Material option rights: The transaction price allocated to the options rights, which are considered material rights, is deferred until the period that Novartis elects to exercise its option right to license and commercialize the underlying immunology program. The Company will recognize the portion of the transaction price allocated to the option rights upon exercise. The Company has no further obligations to perform research services subsequent to the option exercise.

To date through December 31, 2025,$1.8 million of revenue related to the 2025 Novartis Agreement has been recognized as collaboration revenue in the consolidated statements of operations and comprehensive loss. The remaining$118.2 million has been recorded as deferred revenue on the consolidated balance sheets, with$19.0 million included in current liabilities related to performance obligations expected to be completed within 12 months from December 31, 2025 and$99.2 million included in non-current liabilities related to performance obligations expected to be completed later than 12 months from December 31, 2025. The total transaction price of $180 million includes $60 million of future option maintenance payments which are not included in deferred revenue on the consolidated balance sheet.

The following table summarizes the unearned amount of the 2025 Novartis Agreement transaction price allocated to the performance obligations (in thousands):

The Company expects that that the remaining deferred revenue for the license and research services for a named immunology target and research services for two additional immunology targets to be recognized within 57 months. The deferred revenue related to material right license options will be recognized when Novartis exercises such options rights or at the expiration of the option rights. Due to the uncertain nature of the research and development being performed by the Company, it may take longer than anticipated to recognize revenue related to the performance obligations related to research services.

10. Equity

Undesignated preferred stock

The Company had 10,000,000 shares authorized of undesignated preferred stock, par value of $0.0001, of whichno shares were issued and outstanding as of December 31, 2025.

Common stock

The Company had 500,000,000 shares of common stock authorized, of which 65,543,723 shares were issued and outstanding as of December 31, 2025.

Additionally, the Company has issued pre-funded warrants, to purchase 20,638,924 shares of the Company's common stock to accredited investors. The pre-funded warrants are immediately exercisable at an exercise price of $0.0001 per share. The pre-funded warrants are exercisable at any time after the date of issuance. A holder of a pre-funded warrant may not exercise such pre-funded warrant if the holder, together with its affiliates, would beneficially own more than 4.99% (or, at the election of the holder, up to 19.99% of the number of shares of the Company’s common stock outstanding immediately after giving effect to such exercise. No pre-funded warrants have been exercised as of December 31, 2025.

The Company has assessed the pre-funded warrants for appropriate equity or liability classification pursuant to the Company’s accounting policy described in Note 2, Summary of significant accounting policies. During this assessment, the Company determined the pre-funded warrants are a freestanding instrument that does not meet the definition of a liability pursuant to ASC 480 and does not meet the definition of a derivative pursuant to ASC 815. The pre-funded warrants are indexed to the Company’s common stock and meets all other conditions for equity classification under ASC 480 and ASC 815. Based on the results of this assessment, the Company concluded that the pre-funded warrants are a freestanding equity-linked financial instrument that meets the criteria for equity classification under ASC 480 and ASC 815. Accordingly, the pre-funded warrants are classified as equity and is accounted for as a component of additional paid-in capital at the time of issuance. The Company also determined that the pre-funded warrants should be included in the determination of basic and diluted earnings per share in accordance with ASC 260, Earnings per Share.

The holders of common stock are entitled to dividends when and if declared by the Company's board of directors, subject to the preferences applicable to any outstanding shares of preferred stock. The Company's board of directors hasnot declared any dividends and the Company hasnot paid any dividends.

The holders of common stock are entitled toone vote per share on all matters to be voted upon by the stockholders.

As of December 31, 2025 and 2024, the Company has reserved the following shares of common stock for the exercise of stock options, vesting of restricted stock and pre-funded warrants:

In July 2022, the Company entered into a sales agreement, or the 2022 Sales Agreement, with Jefferies LLC, or Jefferies, as amended on March 20, 2025, pursuant to which the Company could offer and sell shares of its common stock pursuant to the then-effective prospectus from time to time in “at-the-market” offerings through Jefferies, as the Company’s sales agent. In connection with the 2022 Sales Agreement, the Company also filed a prospectus supplement with the SEC on February 11, 2026, for the offer and sale of up to $100.0 millionof sharesof common stock from time to time through the sales agent. See Note 16, Subsequent events, for additional information regarding the at-the-market offerings.

The Company agreed to pay Jefferies a commission of up to 3.0% of the gross proceeds of any shares sold by Jefferies under the Sales Agreement. During the year ended December 31, 2025, the Company sold 2,955,082 shares of common stock under the Sales Agreement for aggregate gross proceeds of$25.0 million, or aggregate net proceeds of$23.9 million after deducting sales agent discounts, commissions, and other offering costs. During the year ended December 31, 2024, the Company sold 130,506 shares of common stock under the Sales Agreement for aggregate gross proceeds of$1.0 million, or aggregate net proceeds of$0.9 million after deducting sales agent discounts, commissions, and other offering costs.

Underwritten public offerings

In May 2024, the Company entered into an underwriting agreement with TD Securities (USA) LLC, as representative of the several underwriters, related to an underwritten public offering, or the 2024 Offering, of 10,638,476 shares of common stock at a price of $4.70 per share, and, in lieu of common stock to certain investors, pre-funded warrants to purchase 10,638,524 shares of common stock at a price of $4.6999 per pre-funded warrant, which represents the price per share at which shares of common stock were sold in this 2024 Offering, minus $0.0001, which is the exercise price of each pre-funded warrant. The pre-funded warrants are immediately exercisable and may be exercised at any time until the pre-funded warrants are exercised in full. Aggregate gross proceeds from the 2024 Offering were $100 million, or aggregate net proceeds of $96.4 million after deducting the underwriter discounts, commissions, and other offering costs.

In January 2026, the Company entered into an underwriting agreement with Jefferies LLC, TD Securities (USA) LLC, and Piper Sandler & Co. as representatives of the several underwriters, related to an underwritten public offering, or the 2026 Offering, of 13,000,000 shares of common stock at a price of $24.00 per share, and, in lieu of common stock to certain investors, pre-funded warrants to purchase 1,375,000 shares of common stock at a price of $23.9999 per pre-funded warrant, which represents the price per share at which shares of common stock were sold in the 2026 Offering, minus $0.0001, which is the exercise price of each pre-funded warrant. The pre-funded warrants are immediately exercisable and may be exercised at any time until the pre-funded warrants are exercised in full. Aggregate gross proceeds from the 2026 Offering were $345.0 million, or aggregate net proceeds of$323.8 million after deducting the underwriter discounts, commissions, and other offering costs. See Note 16, Subsequent events, for additional information regarding the 2026 Offering.

11. Stock-based compensation

2020 Stock incentive plan

The Company's 2020 Stock Option and Grant Plan, or the 2020 Plan, provided for the Company to grant stock options, restricted stock, and other stock awards, to employees, non-employee directors, and consultants. Upon the effectiveness of the 2021 Plan (as defined below), no further issuances were made under the 2020 Plan.

2021 Stock incentive plan

The Company’s 2021 Stock Option and Incentive Plan, or the 2021 Plan, was approved by the Company’s board of directors on May 28, 2021 and the Company’s stockholders on June 17, 2021, and became effective on the date immediately prior to the date on which the registration statement for the Company’s initial public offering, or IPO, was declared effective. The 2021 Plan provides for the grant of incentive stock options; non-qualified stock options; stock appreciation rights; restricted stock units, or RSUs; restricted stock awards; unrestricted stock awards; cash-based awards and dividend equivalent rights to the Company’s officers, employees, directors and consultants. The number of shares initially reserved for issuance under the 2021 Plan was 4,903,145. Under the evergreen provision of the 2021 Plan, the shares available for issuance under the 2021 Plan will be automatically increased each January 1st by 5% of the outstanding number of shares of the Company’s common stock on the immediately preceding December 31st or such lesser number of shares as may be determined by the Company’s compensation, nomination and corporate governance committee. Effective January 1, 2025, the number of shares available under the 2021 Plan automatically increased by 3,075,372 shares pursuant to the evergreen provision of the 2021 Plan. As of December 31, 2025,2,271,328 shares were available for issuance under the 2021 Plan.

2021 Employee stock purchase plan

The Company’s 2021 Employee Stock Purchase Plan, or the 2021 ESPP, was approved by the Company’s board of directors on May 28, 2021 and the Company’s stockholders on June 17, 2021, and became effective on the date immediately prior to the date on which the registration statement for the Company’s IPO was declared effective. A total of 439,849 sharesof the Company’s common stock were initially reserved for issuance under the

2021 ESPP. The shares available for issuance under the 2021 ESPP will be automatically increased on each January 1st through January 1, 2031, by the least of (i)439,849 shares of the Company’s common stock, (ii)1% of the outstanding number of shares of the Company’s common stock on the immediately preceding December 31st or (iii) such lesser number of shares of the Company’s common stock as determined by the plan administrator of the 2021 ESPP. Effective January 1, 2025, the number of shares available under the 2021 ESPP automatically increased by 439,849 shares pursuant to the evergreen provision of the 2021 ESPP. As of December 31, 2025,1,685,755 shares were available for issuance under the 2021 ESPP.

Stock option activity

The following summarizes stock option activity:

The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the estimated fair value of the Company’s common stock. The weighted average grant date fair value of options granted during the years ended December 31, 2025 and 2024 was$5.16 and$4.13 per share, respectively. The total intrinsic value of options exercised during the years ended December 31, 2025 and 2024 was$3.6 million and$1.0 million, respectively.

Fair value of stock option awards

The Company estimates the fair value of stock option awards on the grant date using Black-Scholes. The fair value of options granted were estimated using the following weighted-average assumptions:

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

Expected term: The Company’s expected term represents the period that options are expected to be outstanding and is determined using the simplified method. The Company does not have sufficient historical data to use any other method to estimate expected term.

Expected volatility: The Company has limited information on the volatility of stock options as the shares were not actively traded on any public markets prior to June 24, 2021. The expected volatility was derived from the Company's available stock price history and the historical stock volatilities of comparable peer public companies within its industry based on their similarities to the Company, including life cycle stage, therapeutic focus and size over a period equivalent to the expected term of the stock-based awards.

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

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

Restricted stock unit activity

Starting in 2022, the Company granted RSUs to employees under the 2021 Plan. Each of the RSUs represents the right to receive one share of the Company’s common stock upon vesting. The RSUs will typically vest over two or four years provided the individual remains in continuous service of the Company. Accordingly, stock-based compensation expense for each RSU is recognized on a straight-line basis over the vesting term. The fair value of each RSU is based on the closing price of the Company’s common stock on the date of grant.

The following summarizes RSU activity:

The aggregate fair value of RSUs that vested during each of the years ended December 31, 2025 and 2024 was$0.5 million. The weighted average grant date fair value of RSUs that vested during the years ended December 31, 2025 and 2024 was$7.55 per share and$8.42 per share, respectively.

Stock-based compensation expense

Stock-based compensation expense is classified as follows (in thousands):

As of December 31, 2025, total unrecognized stock-based compensation cost related to unvested stock options and restricted stock units was$24.2 million and$4.1 million, respectively. The Company expects to recognize this remaining cost over a weighted average period of 2.3 years and 3.0 years, respectively.

12. Income taxes

The Company has incurred net operating losses for all the periods presented. The Company has not reflected the benefit of any such net operating loss carryforwards, or NOLs, in the accompanying consolidated financial statements. Domestic and foreign components of net loss are as follows (in thousands):

Income taxes paid, net of refunds received, are as follows (in thousands):

The (benefit) expense for income taxes consists of the following (in thousands):

The effective tax rate for the years ended December 31, 2025 and 2024 is different from the federal statutory rate primarily due to the valuation allowance against deferred tax assets as a result of insufficient sources of income. The reconciliation of the federal statutory income tax rate to the Company’s effective income tax rate is as follows:

For the years ended December 31, 2025 and 2024, state and local income taxes in Massachusetts comprise the majority of the state and local income taxes, net of federal effect category.

Deferred income taxes reflect the net effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The principal components of the Company’s deferred tax assets consisted of the following (in thousands):

The Tax Cuts and Jobs Act resulted in significant changes to the treatment of research and developmental expenditures under Section 174 of the Internal Revenue Code. For tax years beginning after December 31, 2021, taxpayers are required to capitalize and amortize all research and developmental expenditures that are paid or incurred in connection with their trade or business. Per the One Big Beautiful Bill Act, effective July 4, 2025, taxpayers are still required to capitalize foreign research and development expenditures over 15 years, but now have the opportunity to deduct domestic research and development expenditures under IRC 174A. The Company has elected to continue to amortize prior year domestic capitalized costs until the amortization of such costs is complete. For the year ended December 31, 2025, the Company didnot capitalize any research and developmental expenditures for income tax purposes. As of December 31, 2024, the Company capitalized $11.5 million of research and developmental expenditures for income tax purposes.

The Company has incurred annual net operating losses in each year since inception. The Company has not reflected the benefit of any such NOLs in the consolidated financial statements. Due to the Company’s history of losses, and lack of other positive evidence, the Company has determined that it is more likely than not that its net deferred tax assets will not be realized, and therefore, the net deferred tax assets are fully offset by a valuation allowance at December 31, 2025 and 2024. The Company increased its valuation allowance by $1.5 million for the year ended December 31, 2025 in order to maintain a full valuation allowance against its deferred tax assets.

As required under ASU 2023-09, the Company has included only the portion of the valuation allowance related to federal deferred tax assets in the "change in valuation allowance" line of the rate reconciliation. The following table presents a reconciliation of the total change in the valuation allowance (in thousands):

As of December 31, 2025, the Company had federal net operating loss carryforwards, or NOLs, of $10.0 million and federal tax credits of $5.5 million available to offset tax liabilities. The Company’s federal NOLs have an indefinite life and federal tax credit carryforwards begin to expire in 2040. The Company also had gross foreign NOLs of $374.5 million that begin to expire in 2026. The Company also had gross state NOLs of $26.0 million that began to expire in 2039. The Company also had gross state tax credits of $4.5 million which are available to offset state tax liabilities and begin to expire in 2026. Federal and state NOLs and tax credit carryforwards are also subject to annual limitations in the event that cumulative changes in the ownership interests of significant stockholders exceed 50%over a three-year period, as defined under Sections 382 and 383 of the Internal Revenue Code of 1986. The Company completed an analysis as of December 31, 2023 and determined that an ownership change occurred on September 14, 2020 and October 30, 2023. As a result of these ownership changes, the utilization of the Company’s net operating loss carryforwards is subject to an annual limitation of

$0.3 million for attributes accumulated prior to September 14, 2020 and $0.8 million for the attributes generated prior to October 30, 2023, which is reflected in the numbers presented above.

The Company determines its uncertain tax positions based on whether and how much of a tax benefit taken by the Company in its tax filings is more likely than not to be sustained upon examination by the relevant income tax

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands):

The Company recognizes interest and penalties related to unrecognized tax benefits in U.S. federal, state, and foreign income tax expense. For the years ended December 31, 2025 and 2024, the Company didnot have unrecognized tax benefits.

The Company files income tax returns in the U.S., Switzerland and Massachusetts. The Company is not currently under examination by any taxing authority for any open tax year. Due to NOLs, all years remain open for income tax examination. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the Internal Revenue Service, or IRS, or state tax authorities to the extent utilized in a future period. No federal, foreign, or state tax audits are currently in process.

13. Employee retirement plans

Defined benefit plan

The Company, in compliance with Swiss Law, is contracted with AXA, for the provision of pension benefits in a defined benefit plan. All benefits are organized in a semi-autonomous collective foundation within the framework of the contract with AXA. Insurance benefits due are paid directly to the entitled persons by AXA in the name of and for the account of the collective foundation. The pension plan is financed by contributions of both employees and the Company.

The contract between the Company and the collective foundation can be terminated by either side. In the event of a termination, the Company would have an obligation to find alternative pension arrangements for its employees. Because there is no guarantee that the employee pension arrangements would be continued under the same conditions, there is a risk, albeit remote, that a pension obligation may fall on the Company.

The pension assets are pooled for all affiliated companies; the investment of assets is done by the governing bodies of the collective foundation.

The following table represents the changes in benefit obligations and plan assets and the net amount recognized on the consolidated balance sheets (in thousands):

The net pension cost was as follows (in thousands):

The provision for pension benefit obligation recognized in other comprehensive loss was as follows (in thousands):

The assumptions used to measure the projected benefit obligation and net pension costs were as follows:

Estimated benefit payments, which reflect future expected service, are expected to be paid as follows (in thousands):

Defined contribution plans

In February 2021, the Company adopted a defined contribution plan intended to qualify under Section 401(k) of the Internal Revenue Code covering all eligible U.S. based employees of the Company. All employees are eligible to become participants of the plan immediately upon hire. Each active employee may elect, voluntarily, to contribute a percentage of their compensation to the plan each year, subject to certain limitations. The Company reserves the right, but is not obligated, to make additional contributions to this plan. The Company makes safe-harbor match contributions of 100% of the first 4% of each participant’s eligible compensation. In January 2024, the Company adopted a defined contribution supplemental pension plan for eligible Swiss based employees defined by Swiss Law Art.1e BVV 2, or the 1e Plan. Employees earning above a defined threshold are eligible and automatically enrolled in the 1e Plan and required contributions are determined by age and salary under Swiss Law. The Company and the employee share the costs of the 1e Plan. The Company recorded$1.0 million and$0.8 million in defined contribution related expenses during the years ended December 31, 2025 and 2024, respectively.

14. Net loss per common share

Basic and diluted net loss per share is calculated based upon the weighted-average number of shares of common stock outstanding during the period. Shares of the Company's common stock underlying pre-funded warrants are included in the calculation of the basic and diluted earnings per share. Basic and diluted net loss per share are as follows (in thousands except share and per share amounts):

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

15. Segment data

The Company defines its segments based on the way in which internally reported financial information is regularly reviewed by the chief operating decision maker, or CODM, to analyze financial performance, make decisions, and allocate resources. The Company manages its operations as a single operating and reportable segment committed to developing a portfolio of novel and proprietary MGDs. MGDs are small molecule drugs that employ the body’s natural protein destruction mechanisms to selectively degrade therapeutically-relevant proteins. As the internal reporting is based on the consolidated results, the Company has identifiedone operating and reportable segment. The CODM uses net income (loss) in the budget and forecasting process and considers budget-to-actual variances on a quarterly basis when making decisions about the allocation of operating and capital resources. The measure of the operating segment assets is reported on the consolidated balance sheet as total assets.

The accounting policies used in the segment reporting are the same as those described in Note 2, Summary of significant accounting policies. The Company’s CODM is the Chief Executive Officer.

The Company's reportable segment net revenues and loss for the years ended December 31, 2025 and 2024, consisted of the following:

Other development and discovery expenses are related to the development of our QuEENTM discovery engine and our disclosed and undisclosed programs, including CDK2 and CCNE1. The Company's tangible assets are held in the U.S. and Switzerland, with 29% and 28% of the assets held in Switzerland as of December 31, 2025 and 2024, respectively. The Company's collaboration revenue is generated in the U.S. and Switzerland, with 90% and 100% of the collaboration revenue generated in Switzerland during the years ended December 31, 2025 and 2024, respectively.

16. Subsequent events

2026 Offering

In January 2026, the Company entered into an underwriting agreement with Jefferies LLC, TD Securities (USA) LLC, and Piper Sandler & Co. as representatives of the several underwriters, related to the 2026 Offering of 13,000,000 shares of common stock at a price of $24.00 per share, and, in lieu of common stock to certain investors, pre-funded warrants to purchase 1,375,000 shares of common stock at a price of $23.9999 per pre-funded warrant, which represents the price per share at which shares of common stock were sold in the 2026 Offering, minus $0.0001, which is the exercise price of each pre-funded warrant. The 13,000,000 shares of common stock includes the full exercise by the underwriters of their option to purchase an additional 1,875,000 shares of common stock at the public offering price. The pre-funded warrants are immediately exercisable and may be exercised at any time until the pre-funded warrants are exercised in full. To date, one pre-funded warrant holder has exercised its pre-funded warrant to purchase 750,000 shares of common stock. Aggregate gross proceeds from the 2026 Offering were $345.0 million and aggregate net proceeds were approximately$323.8 million after deducting the underwriter discounts, commissions, and other offering costs.

Effective January 7, 2026, the Company terminated the $150 million prospectus pursuant to which it had been able to sell shares from time to time in “at-the-market” offerings under its 2022 Sales Agreement with Jefferies as the Company’s sales agent.

On February 11, 2026, the Company filed with the SEC a prospectus for $100 million, pursuant to which it may sell shares from time to time in “at-the-market” offerings under its 2022 Sales Agreement with Jefferies as the Company's sales agent.