ALMS US Equity☆

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

You should read the following discussion and analysis of our financial condition and results of operations in conjunction with our consolidated financial statements and the related notes and other financial information included elsewhere in this Annual Report on Form 10-K. This discussion and analysis and other parts of this Annual Report on Form 10-K contain forward-looking statements based upon current beliefs, plans and expectations related to future events and our future financial performance that involve risks, uncertainties and assumptions, such as statements regarding our intentions, plans, objectives and expectations for our business. Our actual results and the timing of selected events could differ materially from those described in or implied by these forward-looking statements as a result of several factors, including those set forth under Part I, Item 1A. “Risk Factors” in this Annual Report on Form 10-K. See also the section titled “Special Note Regarding Forward-Looking Statements.”

Overview

Our mission is to significantly improve the lives of patients by replacing broad immunosuppression with targeted therapies. Our name, Alumis, captures our mission to enlighten immunology, and is inspired by the words “allumer”—French for illuminate—and “immunis”—Latin for the immune system.

We are a clinical stage biopharmaceutical company with an initial focus on developing our two TYK2 inhibitors: envu, formerly known as ESK-001, a second-generation inhibitor that we are developing to maximize target inhibition and optimize tolerability, and A-005, a CNS penetrant molecule. Envu is currently being evaluated in an ongoing Phase 2 OLE trial, as well as a Phase 3 LTE trial in patients with PsO and we plan to submit an NDA for envu in PsO to the FDA in the second half of 2026. Envu completed enrollment in the pivotal Phase 3 ONWARD1 and ONWARD2 clinical trials in patients with PsO, and we reported positive topline results in the first quarter of 2026. In addition, envu is currently being evaluated in a Phase 2 clinical trial in patients with SLE, for which we expect to report topline results in the third quarter of 2026. We are currently evaluating additional immune-mediated disease indications for envu, beyond PsO and SLE, and for A-005 in CNS and peripheral diseases. In April 2024, we initiated our Phase 1 program of A-005 in healthy volunteers and reported initial results in December 2024. In addition, in connection with the ACELYRIN Merger, we acquired lonigutamab, a subcutaneously delivered, monoclonal antibody targeting IGF-1R for the potential treatment of TED. We are continuing to evaluate the development program for lonigutamab and its potential differentiation in a capital efficient manner.

Alumis was incubated by Foresite Labs and incorporated on January 29, 2021, as a Delaware corporation under the name FL2021-001, Inc. FL2021-001, Inc.’s name was changed to Esker Therapeutics, Inc. in March 2021, and to Alumis Inc. in January 2022.

Since our inception, we have devoted substantially all of our efforts to organizing our company, hiring personnel, business planning, acquiring and developing our product candidates, performing research and development, conducting preclinical studies and clinical trials, establishing and protecting our intellectual property portfolio, raising capital, integrating the acquired ACELYRIN business and personnel, and providing general and administrative support for these activities. We do not have any products approved for sale and have not generated any revenue from product sales. We expect to continue to incur significant and increasing expenses and increasing substantial losses for the foreseeable future as we continue our development of and seek regulatory approvals for our product candidates and commercialize any approved products, seek to expand our product pipeline and invest in our expanded organization following the ACELYRIN Merger. Our ability to achieve and sustain profitability will depend on our ability to successfully develop, obtain regulatory approval for and commercialize our product candidates. There can be no assurance that we will ever achieve profitability, or if achieved, that the revenue or profitability will be sustained on a continuing basis.

To date, we have primarily funded our operations primarily through issuance of common stock, including in connection with the ACELYRIN Merger, our IPO and private placement transaction, the issuance of redeemable convertible preferred stock and convertible promissory notes in private placements, payments received under the Kaken Collaboration Agreement and, most recently, the public offering of common stock which closed on January 9, 2026. In addition, on March 18, 2026, we entered into a Sales Agreement with Cantor, pursuant to which we may offer and sell, from time to time through Cantor, at our option, shares of our common stock having an aggregate offering price of up to $300.0 million.

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As of December 31, 2025, we had $308.5 million in cash, cash equivalents and marketable securities.

We have incurred significant operating losses and negative cash flows since our inception. Our net loss for the years ended December 31, 2025 and 2024 was $243.3 million and $294.2 million, respectively. As of December 31, 2025, we had an accumulated deficit of $901.9 million. Substantially all of our net losses have resulted from costs incurred in connection with our research and development efforts, including acquisitions of in-process research and development assets, and, to a lesser extent, from general and administrative costs associated with our operations. Our net losses and operating losses may fluctuate from quarter to quarter and year to year depending primarily on the timing of acquisition of any new product candidates, the timing of our preclinical studies and clinical trials, our other research and development expenses, and the timing and amount of any milestone or royalty payments due under our existing or future license agreements. We have incurred and will continue to incur costs associated with operating as a public company, including significant legal, audit, accounting, regulatory and tax-related services associated with maintaining compliance with exchange listing and SEC requirements, director and officer liability insurance costs, investor and public relations costs, and other expenses.

We anticipate that our expenses will increase significantly in connection with our ongoing activities, particularly if and as we:

● explore additional indications for our existing product candidates;

● hire additional clinical and scientific personnel;

● obtain, maintain, expand and protect our intellectual property rights;

● operate as a public company.

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We do not expect to generate revenue from any product candidates that we develop until we obtain regulatory approval for one or more of such product candidates and commercialize our products or enter into collaboration agreements with third parties. Because of the numerous risks and uncertainties associated with biopharmaceutical product development, we may never achieve or sustain profitability and, unless and until we are able to develop and commercialize our product candidates, we will need to continue to raise additional capital. Until such time as we can generate significant revenue from product sales, if ever, we expect to finance our operations through public or private equity or debt financings, or potentially other capital sources, such as collaboration or licensing arrangements with third parties or other strategic transactions. There are no assurances that we will be successful in obtaining an adequate level of financing to support our business plans when needed on acceptable terms, or at all. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the ownership interest of our stockholders will be or could be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our common stockholders. Debt financing and equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If we raise additional funds through collaboration or licensing arrangements with third parties or other strategic transactions, we may have to relinquish rights to our intellectual property, future revenue streams, research programs, or product candidates or grant licenses on terms that may not be favorable to us. If we are unable to raise capital as and when needed, or on attractive terms, we may have to significantly delay, reduce, or discontinue the development and commercialization of our product candidates or scale back or terminate our pursuit of new in-licenses and acquisitions.

We do not currently own or operate any manufacturing facility. We rely on CMOs to produce our product candidates in accordance with the FDA current cGMP regulations for use in our clinical studies. We have entered into development and manufacturing agreements with various CMOs relating to process development, manufacturing of drug substance and drug product, and quality testing of our product candidates. We expect to rely on our CMOs in the future for the manufacturing of our product candidates in order to expedite readiness for future clinical trials. Most of these CMOs have demonstrated capability in preparation of materials for commercialization. Additionally, we may decide to build our own manufacturing facility in the future to provide us with greater flexibility and control over our clinical or commercial manufacturing needs.

Given our stage of development, we do not yet have a fully established marketing or sales organization or commercial infrastructure; however, we have begun building foundational capabilities and intend to continue expanding the necessary sales, marketing and commercialization capabilities and infrastructure over time as our product candidates advance through clinical development and regulatory approval. We expect to spend a significant amount in commercial development and marketing costs prior to obtaining regulatory and marketing approval of one or more of our product candidates.

IPO and Concurrent Private Placement

On July 1, 2024, we completed our IPO, pursuant to which we issued and sold 13,125,000 shares of our common stock at $16.00 price per share to the public. Net proceeds from the IPO were $193.3 million, after deducting underwriting discounts and commissions and other offering costs totaling $16.7 million. In connection with the IPO, on July 17, 2024, an existing investor and a holder of more than 5% of our capital stock, purchased an additional 2,500,000 shares of our common stock at the IPO price per share for total gross and net proceeds of $40.0 million in a private placement transaction (the “Concurrent Private Placement”).

Immediately prior to the closing of the IPO on July 1, 2024, all of the shares of our redeemable convertible preferred stock then outstanding converted into 28,855,656 shares of Class A common stock and 7,184,908 shares of Class B common stock at a 1-for-4.675 conversion ratio. All outstanding Class A common stock shares and all outstanding Class B common stock shares were redesignated immediately thereafter into the same number of shares of common stock and non-voting common stock, respectively.

ACELYRIN Merger

On February 6, 2025, we entered into a Merger Agreement with ACELYRIN and Merger Sub, a Delaware corporation and a direct wholly owned subsidiary. The Merger Agreement was approved by the disinterested directors on our board of directors and the board of directors of ACELYRIN and was approved by the stockholders of each company on May 13, 2025. On May 21, 2025, we completed the ACELYRIN Merger for a purchase consideration of approximately $238.1

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million that included the issuance of 48,653,549 shares of our common stock and the fair value of replacement awards attributable to pre-combination services, to acquire net assets with a fair value of approximately $426.0 million. See Note 3 to our consolidated financial statements included in Part II, Item 8 of this Annual Report on Form 10-K for additional information.

Our results of operations include the accounts of our wholly owned subsidiaries ACELYRIN and WH2, LLC after the closing of the ACELYRIN Merger, and the accounts of Merger Sub from its incorporation in January 2025 until the ACELYRIN Merger. Accordingly, the results discussed below were impacted by the timing of the ACELYRIN Merger. WH2, LLC has not had any operations or any balances since the closing of the ACELYRIN Merger.

Public Offering of Common Stock

On January 7, 2026, we entered into an underwriting agreement (the “Underwriting Agreement”) with Morgan Stanley & Co. LLC, Leerink Partners LLC and Cantor, as representatives of the several underwriters named therein (collectively, the “Underwriters”), relating to the issuance and sale in a public offering of 17,650,000 shares of our common stock at a price of $17.00 per share. In addition, we granted the Underwriters an option, exercisable for 30 days, to purchase up to 2,647,500 additional shares of common stock at the public offering price, less the underwriting discounts and commissions, which was exercised in full on January 8, 2026. On January 9, 2026, the offering closed and we received net proceeds of $324.4 million, after deducting underwriting discounts and commissions.

Macroeconomic Trends

Our business and results of operations may be affected by worldwide economic conditions, which may continue to be impacted by global macroeconomic challenges and uncertainty in the markets, including severely diminished liquidity and credit availability, rising inflation and monetary supply shifts, rising interest rates, labor shortages, declines in consumer confidence, declines in economic growth, increases in unemployment rates, recession risks and uncertainty about economic and geopolitical stability (for example, related to the evolving U.S. and ex-U.S. tariff landscape). Further, the United States and other countries have imposed and may continue to impose new trade restrictions and export regulations, have levied tariffs and taxes on certain goods, and could continue to significantly increase tariffs on a broad array of goods. For example, in April 2025, the U.S. government imposed a 10% baseline global tariff and in August 2025, the United States imposed higher “reciprocal” tariffs on numerous other territories, including EU member states and South Korea. While the U.S. Supreme Court recently issued a ruling invalidating tariffs imposed by the Trump administration under the International Emergency Economic Powers Act, other tariffs imposed by the U.S. government remain in place, including the 10% global tariff imposed by the Trump administration under Section 122 of the Trade Act of 1974 following the U.S. Supreme Court decision. Moreover, the Bureau of Industry and Security, U.S. Department of Commerce, has initiated an investigation to determine whether pharmaceutical ingredients, including finished drug product, manufactured outside the United States pose a national security risk and should be subject to additional tariffs. The effect of macroeconomic conditions may not be fully reflected in our results of operations until future periods. Moreover, negative macroeconomic conditions could adversely impact our ability to obtain financing in the future on terms acceptable to us, or at all. To date, the macroeconomic trends discussed above have not had a material adverse impact on our business, financial condition or results of operations. If, however, economic uncertainty increases or the global economy worsens, our business, financial condition and results of operations may be harmed.

Components of Results of Operations

Revenue

On March 25, 2025, we entered into the Kaken Collaboration Agreement. Under the terms of the Kaken Collaboration Agreement, we granted to Kaken an exclusive right to develop, manufacture and commercialize envu for dermatology indications in Japan, with options to expand the license, subject to opt-in payments and certain cost-sharing obligations on the part of Kaken, to include rheumatological and gastrointestinal diseases.

Pursuant to the terms of the Kaken Collaboration Agreement, we are responsible for the global development of envu in the dermatology field, and Kaken is responsible for the clinical development, regulatory approvals and commercialization

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of envu in Japan in dermatology and other indications for which Kaken has exercised its option. Kaken is required to use commercially reasonable efforts to conduct all subsequent development, manufacture, and commercialization activities. The Kaken Collaboration Agreement further provides that we will retain rights to envu in all other indications and geographies.

In March 2025, Kaken made an upfront, non-refundable payment of $20.0 million to us. In addition, Kaken will pay us an aggregate of $20.0 million towards global development costs of envu in the dermatology field through the end of 2026 and thereafter will pay a specified share of development costs applicable to the dermatology field, and for any field for which Kaken exercises its option, subject to Kaken's right to opt out of cost-sharing in certain indications in specified circumstances. In addition, Kaken would pay us up to an aggregate of $36.0 million upon the achievement of regulatory milestones and upon Kaken’s exercise of its field expansion options for the rheumatology and gastrointestinal fields. In addition, we are entitled to receive aggregate payments of up to ¥15.5 billion upon the achievement of commercial milestones, plus tiered royalties at percentages ranging from the low double digits into the twenties on aggregate net sales of envu in Japan.

Operating Expenses

Our operating expenses consist of (i) research and development expenses and (ii) general and administrative expenses, and include ACELYRIN’s operations subsequent to the Closing Date.

Research and Development Expenses

Research and development expenses consist of external and internal costs primarily related to acquiring and developing our research pipeline and technologies and clinical development of our product candidates.

External costs include:

Internal costs include:

We have acquired and may continue to acquire the rights to develop and commercialize new product candidates. Upfront payments related to acquired IPR&D assets are recognized as expenses when we determine that the assets acquired do not have alternative future uses. Milestone payments are accrued and expensed when the achievement of the milestone is probable up to the point of regulatory approval and, absent obtaining such approval, have no alternative future use. Milestone payments made after a product’s regulatory approval will be capitalized and amortized over the remaining useful life of the related product.

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We expense research and development costs as incurred. Costs of certain activities are recognized based on an evaluation of the progress to completion of specific tasks. However, payments made prior to the receipt of goods or services that will be used or rendered for future research and development activities are deferred and capitalized as research and development prepaid expenses in our consolidated balance sheets. The capitalized amounts are recognized as expense as the goods are delivered or services are performed. Since our inception and through December 31, 2025, our external research and development expenses were primarily related to the discovery and advancement of programs under our TYK2 platform, including our two most advanced product candidates, envu and A-005. We use internal resources primarily for managing our research, process development, manufacturing and clinical development activities. In particular, with respect to internal costs, we deploy our personnel across all of our research and development activities as our employees work across multiple programs, and therefore the costs cannot be allocated to a particular product candidate or research program.

We expect our research and development expenses to increase substantially for the foreseeable future as we advance our product candidates into and through clinical trials, pursue regulatory approval of our product candidates, build our operational and commercial capabilities for marketing our products, if approved, and expand our pipeline of product candidates. The process of conducting the necessary clinical research to obtain regulatory approval is time-consuming, expensive and uncertain. The actual probability of success for our product candidates may be affected by a variety of factors, including the safety and efficacy of our product candidates, clinical data, investment in our clinical programs, competition, manufacturability and commercial viability. It is possible that we may never receive regulatory approval for any of our product candidates. As a result of the uncertainties discussed above, we are unable to determine the duration and completion of costs of our research and development projects or if, when and to what extent we will generate revenue from the commercialization and sale of our product candidates, if approved by the FDA and other comparable foreign regulatory authorities.

Our future research and development costs may vary significantly based on factors such as:

● the number and scope of preclinical and clinical programs we decide to pursue;

● the costs and timing of manufacturing of our product candidates;

● delays or difficulties in adding trial sites and enrolling participants;

● patient drop-out or discontinuation rates;

● additional safety monitoring if requested by regulatory authorities;

● the phase of development of our product candidates;

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● changes in the competitive outlook;

A change in the outcome of any of these variables with respect to the development of any of our product candidates could significantly change the costs and timing associated with the development of that product candidate.

General and Administrative Expenses

Our general and administrative expenses consist primarily of personnel-related costs, legal and consulting services, including those relating to intellectual property and corporate matters, marketing expenses and allocated facilities and other overhead costs, including software licenses, computer supplies, insurance and other miscellaneous expenses. Personnel-related costs include salaries, annual bonuses, benefits, travel and meal expenses and stock-based compensation expense for our general and administrative personnel.

We expect that our general and administrative expenses will increase substantially in the future as a result of expanding our operations, including hiring personnel, preparing for potential commercialization of our product candidates and facility occupancy costs. We also expect to continue incurring costs associated with being a public company, including costs related to accounting, audit, legal, consulting fees, regulatory and tax-related services associated with maintaining compliance with applicable Nasdaq and SEC requirements, additional director and officer insurance costs, and investor and public relations costs.

Other Income (Expense)

Other income (expense) consists primarily of interest income, including amortization of premiums and accretion of discounts on marketable securities, gain on bargain purchase and change in fair value of derivative liability.

At the closing of the ACELYRIN Merger in May 2025, we recognized a gain on bargain purchase which represents the excess of fair value of net assets acquired in the ACELYRIN Merger over the purchase consideration on the Closing Date. The gain on bargain purchase was recognized as other income in the consolidated statements of operations and comprehensive loss as of the Closing Date of the ACELYRIN Merger. See Note 3 to our consolidated financial statements included in Part II, Item 8 of this Annual Report on Form 10-K for additional information.

In March 2024, in connection with our redeemable convertible preferred stock financings, we issued options to purchase additional shares of redeemable convertible preferred stock at a specified price, which were accounted for as derivative liabilities. Changes in fair value of these derivative liabilities were included in the other income (loss) in the consolidated statement of operations and comprehensive loss for each reporting period until the derivatives were settled in May 2024.

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Results of Operations and Comprehensive Loss

Comparison of the Years Ended December 31, 2025 and 2024

The following table summarizes our results of operations for the years ended December 31, 2025 and 2024 (dollars in thousands):

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ ​ ​ Year Ended December 31, ​ ​ ​ Change ​

Revenue: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Collaboration revenue ​ ​ 6,661 ​ ​ — ​ ​ 6,661 ​ * ​

Operating expenses: ​ ​ ​ ​ ​ ​ ​ ​ ​

Other income (expense): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Other income (expense), net ​ ​ (169) ​ ​ (93) ​ ​ (76) ​ 82 %

Income tax benefit ​ ​ 8,561 ​ ​ — ​ ​ 8,561 ​ * ​

* not meaningful

Revenue

For the year ended December 31, 2025, we recognized license revenue of $17.4 million and collaboration revenue of $6.7 million, related to the Kaken Collaboration Agreement. At inception of the contract, we allocated the transaction price to the License Obligation and Development Services Obligation by allocating the transaction price based on the relative standalone selling price of each obligation. The license revenue was recognized upon the transfer of the license to Kaken in March 2025. We expect to recognize revenue under the Development Services Obligation and Manufacturing Services Obligation through the term of the Kaken Collaboration Agreement as the services are performed.See Note 7 to our consolidated financial statements included in Part II, Item 8 of this Annual Report on Form 10-K for additional information.

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Research and Development Expenses

The following table summarizes our external and internal research and development expenses for the years ended December 31, 2025 and 2024 (dollars in thousands):

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Year Ended December 31, ​ Change

External costs: ​ ​ ​ ​ ​ ​ ​ ​ ​

Internal costs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

* not meaningful

​

Research and development expenses increased by $120.4 million, to $386.0 million for the year ended December 31, 2025, from $265.6 million for year ended December 31, 2024.

Milestones related to previously acquired IPR&D assets for the year ended December 31, 2024, included a $23.0 million clinical milestone payment made in connection with the FronThera Acquisition.

CRO, CMO and clinical trials expenses increased by $79.7 million, to $231.1 million for the year ended December 31, 2025, from $151.4 million for the year ended December 31, 2024, primarily due to an increase in clinical trial and CRO expenses related to the progression of our clinical trials for envu and other programs, including costs to support acceleration of clinical trial activities for our Phase 3 ONWARD clinical program, partially offset by a decrease in CMO expenses associated with manufacturing of clinical supplies to support our trials.

Professional consulting services expenses increased by $11.0 million, to $30.2 million for the year ended December 31, 2025, from $19.2 million for the year ended December 31, 2024, primarily due to services to support our clinical trial for envu and other programs.

Other research and development costs decreased by $1.2 million, to $9.1 million for the year ended December 31, 2025, from $10.3 million for the year ended December 31, 2024, primarily due to the timing of preclinical studies.

Personnel-related costs increased by $45.9 million, to $92.7 million for the year ended December 31, 2025, from $46.8 million for the year ended December 31, 2024, primarily due to an increase in research and development headcount and severance costs related to the ACELYRIN Merger, and included an increase in stock-based compensation expense of $11.2 million resulting from equity awards assumed in the ACELYRIN Merger and additional stock options granted.

Facilities and overhead costs increased by $8.0 million, to $22.9 million for the year ended December 31, 2025, from $14.9 million for the year ended December 31, 2024, primarily due to an increase in facility expenses allocated to research and development activities and an increase in information technology costs.

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External Costs by Program

The following table summarizes our external costs by program for the years ended December 31, 2025 and 2024 (in thousands):

​ ​ ​ ​ ​ ​

​ Year Ended December 31,

Lonigutamab ​ 11,905 ​ ​ —

Other programs and research and development activities ​ 24,167 ​ 34,858

Total external research and development expense $ 270,371 ​ $ 203,834

​

During the years ended December 31, 2025 and 2024, our external research and development expenses were primarily related to the clinical development of our envu program and, to a lesser extent, the lonigutamab and A-005 development programs and our research pipeline.

General and Administrative Expenses

General and administrative expenses increased by $56.7 million, to $91.9 million for the year ended December 31, 2025, from $35.2 million for the year ended December 31, 2024.

Personnel-related expenses increased by $28.8 million, to $48.9 million for the year ended December 31, 2025, from $20.0 million for the year ended December 31, 2024, primarily due an increase in general and administrative headcount and severance costs related to the ACELYRIN Merger, and included an increase in stock-based compensation expense of $12.9 million resulting from equity awards assumed in the ACELYRIN Merger and additional stock options granted.

Professional consulting services expenses increased by $28.1 million, to $41.4 million for the year ended December 31, 2025, from $13.3 million for the year ended December 31, 2024, primarily due to the ACELYRIN Merger transaction costs, a loss reserve and an increase in consulting, audit and tax, legal and accounting services to support our growth, public company requirements and business development.

Other Income (Expense), Net

Other income (expense), net increased by $195.4 million, to $201.9 million for the year ended December 31, 2025, from $6.5 million for the year ended December 31, 2024.

A gain on bargain purchase of $187.9 million was recognized at the Closing Date of the ACELYRIN Merger. No such gain was recognized in any other reporting period.

Interest income increased by $2.2 million, to $14.2 million for the year ended December 31, 2025, from $12.0 million for the year ended December 31, 2024, primarily as a result of higher balances of cash equivalents and marketable securities.

We recognized a change in fair value of a derivative liability loss of $5.4 million for the year ended December 31, 2024 related to the derivative liability recognized in connection with our Series C redeemable convertible preferred stock financing entered into in March 2024. The derivative liability was re-measured at fair value and settled in May 2024, when we closed the second tranche of the Series C financing.

Income Tax Benefit

Income tax benefit was $8.6 million for the year ended December 31, 2025, as compared to zero for the year ended December 31, 2024. The income tax benefit was related to the realization of deferred tax assets and valuation allowance release as a result of the ACELYRIN Merger.

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Liquidity, Capital Resources and Capital Requirements

Sources of Liquidity

Since our inception, we have not generated any revenue from product sales and have incurred significant operating losses and negative cash flows from our operations. To date, we have primarily funded our operations through the issuance of common stock, including in connection with the ACELYRIN Merger, our IPO and Concurrent Private Placement, the issuance of redeemable convertible preferred stock and convertible promissory notes in private placements and, most recently, our public offering of common stock which closed on January 9, 2026.

On March 18, 2026, we entered into the Sales Agreement with Cantor as sales agent, pursuant to which we may offer and sell, from time to time through Cantor, at our option, shares of our common stock having an aggregate offering price of up to $300.0 million (the “ATM Shares”). The sales of the ATM Shares will be made by any method permitted that is deemed to be an “at-the-market” equity offering as defined in Rule 415(a)(4) promulgated under the Securities Act, including sales made directly on or through the Nasdaq Global Select Market. We agreed to pay Cantor a commission of up to 3.0% of the aggregate gross proceeds from any ATM Shares sold by Cantor.

Based on our current operating plan, our existing cash, cash equivalents and marketable securities of $308.5 million as of December 31, 2025, as well as net proceeds of $324.4 million, after deducting underwriting discounts and commissions, from our public offering of common stock, which closed on January 9, 2026, will be sufficient to meet our operating and capital requirements for at least 12 months from the date of issuance of our consolidated financial statements included in Part II. Item 8 of this Annual Report on Form 10-K. We expect to continue to incur substantial losses for the foreseeable future, and our transition to profitability will depend upon successful development, approval and commercialization of our product candidates and upon achievement of sufficient revenues to support our cost structure. We do not expect to generate any revenue from commercial product sales unless and until we successfully complete development and obtain regulatory approval for one or more of our product candidates. We may never achieve profitability, and unless we do and until then, we will need to continue to raise additional capital. We will need to raise significant additional capital to fund ongoing research and development activities and maintain future operations. We continuously monitor and, where necessary, may reduce our operating expenses in response to our clinical development progress and our ability and need to raise additional capital through a combination of public and private equity, debt financings, strategic alliances, and licensing arrangements. For example, should any of our ongoing trials not meet our clinical development objectives, we may scale back or discontinue related activities and reallocate our working capital to extend our ability to meet our operating and capital requirements. Our ability to access capital when needed is not assured and, if capital is not available to us when, and in the amounts, needed, on the terms which are favorable, we could be required to delay, scale back, or abandon some or all of our planned development programs and other operations, which could materially harm our business, financial condition and results of operations.

​

Future Funding Requirements

Our primary uses of cash are to fund our operations, which consist primarily of research and development expenditures related to our programs and, to a lesser extent, general and administrative expenditures. We anticipate that we will continue to incur significant and increasing expenses for the foreseeable future as we continue to advance our product candidates, expand our corporate infrastructure, including the costs associated with being a public company, further our research and development initiatives for our product candidates, and incur costs associated with potential commercialization. We are subject to all of the risks typically related to the development of new drug candidates, and we may encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect our business. We anticipate that we will need substantial additional funding in connection with our continuing operations.

We do not have any products approved for sale and have not generated any revenue from product sales since our inception. We do not expect to generate revenue from any product candidates that we develop until we obtain regulatory approval for one or more of such product candidates and commercialize our products or enter into collaboration agreements with third parties. Because of the numerous risks and uncertainties associated with biopharmaceutical product development, we may never achieve or sustain profitability and, unless and until we are able to develop and commercialize our product candidates, we will need to continue to raise additional capital. Until such time as we can generate significant revenue

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from product sales, if ever, we expect to finance our operations through public or private equity or debt financings, or potentially other capital sources, such as collaboration or licensing arrangements with third parties or other strategic transactions. There are no assurances that we will be successful in obtaining an adequate level of financing to support our business plans when needed on acceptable terms, or at all. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the ownership interest of our stockholders will be or could be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our common stockholders. Debt financing and equity financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends. If we raise additional funds through collaboration or licensing arrangements with third parties or other strategic transactions, we may have to relinquish rights to our intellectual property, future revenue streams, research programs, or product candidates or grant licenses on terms that may not be favorable to us. If we are unable to raise capital as and when needed, or on attractive terms, we may have to significantly delay, reduce, or discontinue the development and commercialization of our product candidates or scale back or terminate our pursuit of new in-licenses and acquisitions.

Because of the numerous risks and uncertainties associated with research, development and commercialization of our products, we are unable to estimate the exact amount of our operating capital requirements. Our future funding requirements will depend on many factors, including the following:

● the timing of when we pay our operating expenses;

● the effect of competing technological and market developments;

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● the costs associated with being a public company; and

Cash Flows

The following table summarizes our cash flows for the years ended December 31, 2025 and 2024 (in thousands):

​ ​ ​ ​ ​ ​ ​

​ ​ ​ ​ ​

​ ​ Year Ended December 31,

Net cash used in operating activities ​ $ (369,523) ​ $ (255,078)

Net cash provided by (used in) investing activities ​ ​ 287,877 ​ ​ (113,790)

Net cash provided by financing activities 2,067 492,367

Operating Activities

Net cash used in operating activities was $369.5 million and $255.1 million for the years ended December 31, 2025 and 2024, respectively.

Net cash used in operating activities for the year ended December 31, 2025 was due to our net loss for the period of $243.3 million and changes in non-cash items totaling $144.0 million, partially offset by changes in operating assets and liabilities of $17.8 million. Non-cash items included $187.9 million related to gain on bargain purchase in connection with the ACELYRIN Merger and net accretion of discounts on marketable securities of $5.3 million, partially offset by $43.5 million related to stock-based compensation expense, $3.5 million related to depreciation and amortization, $1.7 million related to non-cash lease expense and $0.5 million related to impairment of long-lived assets. The changes in operating assets and liabilities primarily included a decrease of $17.2 million in other prepaid expenses and other assets, a decrease of $11.5 million in research and development prepaid expenses, an increase of $6.0 million in other accrued expenses and current liabilities, an increase of $4.1 million in deferred revenue, and an increase of $2.1 million in research and development accrued expenses, partially offset by an $8.6 million decrease in deferred tax liability, a decrease of $6.0 million in accounts payable, an increase of $5.5 million in other assets, non-current and a decrease of $3.2 million in operating lease liabilities.

Net cash used in operating activities for the year ended December 31, 2024 was due to our net loss for the period of $294.2 million, partially offset by changes in non-cash items totaling $24.4 million and changes in operating assets and liabilities of $14.8 million. Non-cash items included $19.5 million related to stock-based compensation expense, $5.4 million related to the change in fair value of the derivative liability and $3.2 million related to depreciation and amortization, partially offset by net accretion of discounts on marketable securities of $3.7 million. The changes in operating assets and liabilities primarily included an increase of $18.2 million in research and development accrued expenses, an increase of $8.5 million in accounts payable and a $3.5 million increase in other accrued expenses and current liabilities, partially offset by an increase of $10.8 million in research and development prepaid expenses, an increase of $2.9 million in other prepaid expenses and other assets and a decrease of $1.9 million in operating lease liabilities.

Investing Activities

Net cash provided by investing activities of $287.9 million for the year ended December 31, 2025, was related to maturities of marketable securities of $448.0 million and cash, cash equivalents and restricted cash acquired in connection with the ACELYRIN Merger of $49.7 million, partially offset by purchases of marketable securities of $209.2 million and by purchases of property and equipment of $0.7 million.

Net cash used in investing activities of $113.8 million for the year ended December 31, 2024, was related to purchases of marketable securities of $240.1 million and purchases of property and equipment of $1.7 million, partially offset by maturities of marketable securities of $128.0 million.

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Financing Activities

Net cash provided by financing activities of $2.1 million for the year ended December 31, 2025 was primarily related to proceeds from the issuance of common stock under the 2024 ESPP (defined below) of $1.6 million and proceeds from issuance of common stock upon exercise of stock options of $0.5 million.

Net cash provided by financing activities of $492.4 million for the year ended December 31, 2024, included $258.5 million proceeds from the issuance of redeemable convertible preferred stock and derivative liability, net of offering costs, $193.3 million proceeds from initial public offering, net of underwriter discounts and commissions and other offering costs, $40.0 million proceeds from a private placement transaction and $0.6 million proceeds from issuance of common stock upon exercise of stock options.

Contractual Obligations and Commitments

Leases

We have operating lease arrangements for office and laboratory space in South San Francisco, California and office space in Southern California. As of December 31, 2025, we had total undiscounted lease payment obligations under non-cancelable leases of $8.5 million payable in the 12 months following December 31, 2025, and $44.5 million payable thereafter.

FronThera Contingent Consideration

On March 5, 2021, we entered into the FronThera Acquisition, and the transaction was accounted for as an asset acquisition. Under the agreement, we are obligated to pay contingent consideration of up to an aggregate of $120.0 million based on the achievement of specified clinical and approval milestones, for up to an aggregate of $70.0 million payable for clinical milestones, and for up to an aggregate of $50.0 million payable for approval milestones, including receipt of first commercialization approval in the United States or certain other jurisdictions, all related to technology acquired under the agreement. In the year ended December 31, 2022, we incurred and made a $37.0 million milestone payment for the first administration of envu to a patient enrolled in a Phase 2 clinical trial of envu, which was recorded in research and development expenses in the consolidated statement of operations and comprehensive loss. In July 2024, we met a milestone in connection with the first administration of envu to a patient enrolled in a Phase 3 clinical trial of envu and made a $23.0 million milestone payment in August 2024, which was recorded in research and development expenses in the consolidated statement of operations and comprehensive loss for the year ended December 31, 2024. No other milestones were achieved or were probable of being achieved as of December 31, 2025.

License and Commercialization Agreement with Pierre Fabre

Upon the closing of the Merger Agreement, we became the successor to ACELYRIN’s rights and obligations under the Pierre Fabre Agreement. We received certain exclusive worldwide licenses with the right to sublicense certain patents, know-how and other intellectual property to develop, manufacture, use and commercialize lonigutamab for non-oncology therapeutic indications. The license from Pierre Fabre extends to any product containing lonigutamab (excluding any fragments or derivatives) as its sole active ingredient (each, a “PF Licensed Product”). The Pierre Fabre Agreement prohibits us from using the licensed intellectual property in any antibody drug conjugate, multi-specific antibodies or any other derivatives of lonigutamab.

We are obligated to (i) make payments of up to $100.5 million upon the achievement of various development and regulatory milestones, (ii) make milestone payments of up to $390.0 million upon the achievement of certain commercial milestones, and (iii) pay tiered royalties in the high single-digit to low-teen percentages to Pierre Fabre on worldwide net sales in a given calendar year. Royalties will be payable for each PF Licensed Product in a given country during a period commencing upon the first commercial sale of such PF Licensed Product in such country and continuing until the latest of (a) 10 years after such first commercial sale, (b) expiration of last-to-expire valid claim in a licensed patent in such country and (c) expiration of regulatory exclusivity for such PF Licensed Product in such country. In the event we enter into a sublicense with a third party, we must also share with Pierre Fabre a percentage of any revenues from option fees, upfront payments, license maintenance fees, milestone payments or the like generated from the sublicense. Such percentage may

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be between the high single-digits to the low thirties based on which stage of development of a PF Licensed Product the sublicense relates to.

Unless earlier terminated, the Pierre Fabre Agreement will continue on a PF Licensed Product-by-PF Licensed Product and country-by-country basis until there are no more royalty payments owed to Pierre Fabre on any PF Licensed Product thereunder. Either party may terminate the Pierre Fabre Agreement upon an uncured material breach, or upon the bankruptcy or insolvency of the other party. Pierre Fabre may also terminate the agreement if we or any of our affiliates institutes a patent challenge against the licensed patents from Pierre Fabre. We may also terminate the Pierre Fabre Agreement with or without cause upon nine months’ prior written notice, so long as there is no ongoing clinical trial for any PF Licensed Product.

As of December 31, 2025, no milestones were achieved or probable of being achieved.

Purchase Commitments

We enter into contracts in the normal course of business with suppliers, CROs, CMOs and clinical trial sites. Upon the closing of the ACELYRIN Merger, we became the successor to contracts with non-cancellable obligations under ACELYRIN contracts. The total value of non-cancellable obligations under contracts was $1.6 million as of December 31, 2025. This presentation of non-cancellable purchase obligations does not include any estimates of potential reduction of such liabilities related to mitigation obligations of the counterparties in the event of cancellation under the terms of our engagements.

Recently Issued Accounting Pronouncements

A description of recently issued accounting pronouncements that may potentially impact our financial position, results of operations or cash flows is disclosed in Note 2 to our consolidated financial statements included in Part II, Item 8 of this Annual Report on Form 10-K for additional information.

Critical Accounting Policies and Significant Judgments and Estimates

Our management’s discussion and analysis of our financial condition and results of operations is based on our financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The preparation of these consolidated financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported expenses during the reporting period. On an ongoing basis, we evaluate our estimates and assumptions, including but not limited to those related to research and development expenses and accruals, valuation of acquired IPR&D intangible assets, revenue recognition and stock-based compensation expense. These estimates and assumptions are monitored and analyzed by us for changes in facts and circumstances, and material changes in these estimates and assumptions could occur in the future. Our estimates are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Changes in estimates are reflected in reported results for the period in which they become known. Actual results may differ from these estimates under different assumptions or conditions.

Although our significant accounting policies are described in more detail in Note 2 to our consolidated financial statements included in Part II, Item 8 of this Annual Report on Form 10-K, we believe that the following accounting policies are those most critical to the judgments and estimates used in the preparation of our consolidated financial statements.

Research and Development Expenses and Accruals

Research and development costs are expensed as incurred. As part of the process of preparing our financial statements, we are required to estimate our research and development accrued expenses, including those related to clinical trials and manufacturing clinical and preclinical materials. This process involves reviewing open contracts and purchase orders and communicating with our applicable personnel to identify services that have been performed on our behalf and estimating

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the level of service performed and the associated cost incurred for the services when we have not yet been invoiced or otherwise notified of actual costs. Our service providers invoice us in arrears, as well as on a pre-determined schedule or when contractual milestones are met. We make estimates of our research and development accrued expenses as of each balance sheet date in the consolidated financial statements based on facts and circumstances known to us at that time. We periodically confirm the accuracy of the estimates with the service providers and make adjustments if necessary. Examples of estimated research and development accrued expenses include fees paid to:

● vendors in connection with preclinical and clinical development activities;

● CROs in connection with clinical trials; and

Costs for clinical trials and manufacturing activities are recognized based on an evaluation of our vendors’ progress towards completion of specific tasks, using data such as participant enrollment, clinical site activations or information provided to us by our vendors regarding their actual costs incurred. Payments for these activities are based on the terms of individual contracts and payment timing may differ significantly from the period in which the services were performed. We determine accrual estimates through reports from and discussions with applicable personnel and outside service providers as to the progress or state of completion of studies, or the services completed. Our estimates of research and development accrued expenses as of each balance sheet date are based on the facts and circumstances known at the time. Costs that are paid in advance of performance are deferred as a prepaid expense and amortized over the service period as the services are provided.

Although we do not expect our estimates to be materially different from amounts actually incurred, our understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period. To date, there have not been any material adjustments to our prior estimates of research and development accrued expenses. However, due to the nature of estimates, we cannot assure that we will not make changes to our estimates in the future as we become aware of additional information about the status or conduct of our clinical trials and other research activities.

Business Acquisitions, Including Intangible Assets, Goodwill and Contingent Consideration

We account for business combinations, as defined in Accounting Standards Codification (“ASC”) Topic 805, Business Combinations, using the acquisition method of accounting, which generally requires that assets acquired, including IPR&D intangible assets, and liabilities assumed, be recorded at fair value on the consolidated balance sheets as of the acquisition date. The excess of the fair value of the purchase consideration over the fair value of net assets acquired, if any, is recorded as goodwill on the consolidated balance sheet. The excess of the fair value of net assets acquired over the fair value of the purchase consideration, if any, represents negative goodwill, or a gain on bargain purchase, which is recognized in the consolidated statement of operations as of the date of the acquisition.

Calculating the fair value of assets acquired and liabilities assumed requires us to make significant estimates and assumptions. As a result, we may record adjustments to the fair values within the measurement period, which may be up to one year from the acquisition date, with the corresponding offset to goodwill or a gain on bargain purchase.

Transaction costs associated with business combinations are expensed as they are incurred.

Intangible assets related to IPR&D projects acquired are considered to be indefinite-lived until abandonment or completion of the associated R&D efforts, which generally occurs when regulatory approval is obtained. Goodwill and indefinite-lived intangible assets are not amortized and, instead, are tested for impairment annually, in the fourth quarter, or more frequently if events or changes in circumstances indicate that it is more likely than not that the assets are impaired as required by ASC 350 Intangibles – Goodwill and Other. Such events and circumstances may include a significant change in our business climate, economic and industry trends, legal factors, negative operating performance indicators, significant competition or changes in strategy. We perform testing of indefinite-lived intangible assets, other than goodwill, at the

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asset group level using a discounted cash flow model. If the carrying value exceeds the fair value, an impairment loss is recorded for that excess. We would also be required to reduce the carrying amounts of the related assets on our consolidated balance sheet. Determining the fair value of an indefinite-lived intangible asset group requires the application of judgment and involves the use of significant estimates and assumptions, including projections of future cash flows, which include estimated revenues, costs and probabilities of achieving technical and regulatory milestones, and discount rates, among other factors. We base our fair value estimates on assumptions we believe to be reasonable, but which are unpredictable and inherently uncertain. Actual future results may differ from the estimates. Development costs incurred after an acquisition are expensed as they are incurred.

Intangible assets with finite useful lives, which include completed IPR&D projects, are amortized over their estimated useful lives, primarily on a straight-line basis, and are also periodically reviewed for changes in facts or circumstances that may result in an impairment or in a reduction to the estimated useful life of the asset.

In determining the initial fair value of an intangible asset, or when quantitative analysis is required to determine any impairment, we usually use an income approach that discounts expected future cash flows to present value using a discount rate that is based on the estimated weighted-average cost of capital for comparable companies and represents the rate that market participants would use to value the intangible asset. These cash flow models require the use of Level 3 fair value measurements and inputs, including estimated revenues, costs and probabilities of technical and regulatory milestones, among other factors.

If we are required to pay future consideration that is contingent upon the achievement of specified development, regulatory approval or sales-based milestone events, then the estimated fair value of contingent consideration liabilities is recognized in the consolidated balance sheet as of the date of the acquisition. Each reporting period thereafter, we revalue these obligations and record increases or decreases in their fair value on the consolidated statements of operations until such time that the payment is made or obligations expire.

Revenue Recognition

We earn revenue from collaboration agreements that allow collaborators to develop, manufacture and commercialize product candidates. Collaboration revenue is recognized in accordance with ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”). Arrangements with collaborators may include intellectual property licenses, research and development services, manufacturing services for clinical and commercial supply and participation in joint steering committees.

We recognize collaboration revenue in an amount that reflects the consideration that we expect to receive in exchange for those goods or services when our collaborator, or customer, obtains control of promised goods or services. We follow a five-step approach: (i) identify the contract with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations, and (v) recognize revenue when (or as) the customer obtains control of the product or service.

At contract inception, once the contract is determined to be within the scope of ASC 606, we assess the goods or services promised within the contract to determine whether each promised good or service is a performance obligation. Performance obligations are promises in a contract to transfer a distinct good or service to the customer that (i) the customer can benefit from on its own or together with other readily available resources and (ii) are separately identifiable from other promises in the contract. Goods or services that are not individually distinct performance obligations are combined with other promised goods or services until such combined group of promises meet the requirements of a performance obligation.

We determine the transaction price based on the amount of consideration we are entitled to receive in exchange for the transfer of control of a product or a service to the customer. Consideration may be fixed, variable, or a combination of both. Payments to us under these arrangements typically include one or more of the following: non-refundable upfront payments, reimbursement for research services, payments for clinical supplies, research, development or regulatory milestone payments, profit-sharing arrangements, and royalty and commercial sales milestone payments. Variable consideration, such as performance-based milestones, are included in the total consideration if we expect to receive such consideration and if it is probable that the inclusion of the variable consideration will not result in a significant reversal in

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the cumulative amount of revenue recognized under the arrangement. We account for cost reimbursements included in the transaction price using the expected value method. We exclude sales-based royalty and milestone payments from the total consideration we expect to receive until the underlying sales occur because the license to our intellectual property is deemed to be the predominant item to which the royalties or milestones relate as it is the primary driver of value in the collaboration arrangements.

We then allocate the transaction price to each distinct performance obligation based on the relative standalone selling price. Key assumptions to determine the standalone selling price may include forecasted revenues, development timelines, probabilities of technical and regulatory success, and the expected level of effort for research and development services. We recognize revenue associated with each performance obligation as the control over the promised goods or services transfer to our collaborators which occurs either at a point in time or over time. If control transfers over time, revenue is recognized by using a method of measuring progress that best depicts the transfer of goods or services. We evaluate the measure of progress and related inputs each reporting period and any resulting adjustments to revenue are recorded on a cumulative catch-up basis. Consideration allocated to options that include material rights is deferred until the options are exercised or expire.

Stock-Based Compensation Expense

We account for stock-based compensation expense in accordance with ASC Topic 718, Compensation-Stock Compensation (“ASC 718”). We grant stock-based awards to employees, directors and non-employee consultants in the form of stock options and restricted stock units (“RSUs”) to purchase shares of our common stock. Compensation expense for stock options with service-based vesting conditions is measured at the fair value of the award on the grant date and is recognized over the requisite service period, which is generally the vesting period, using the straight-line method. We estimate the fair value of each stock option with service-based vesting on the date of grant using the Black-Scholes option pricing model. This model requires the use of subjective assumptions to determine the fair value of each stock-based award, including:

​

We have also granted stock options with graded vesting based on market, service and performance conditions. At the grant date, the fair value of these stock options was estimated using a Monte Carlo simulation model, which uses a distribution of potential outcomes over the vesting period. The assumptions utilized in the calculation included our expected common stock price, expected volatility, risk-free rate and expected term. Stock-based compensation expense for these awards is recognized on a straight-line basis over the requisite service period, which is the longer of the explicit service period of the service condition and the derived service period of the market condition, as determined for each separately vesting portion of the awards as if each award was, in substance, multiple awards.

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Stock-based compensation expense related to stock purchase rights under our 2024 Employee Stock Purchase Plan (the “2024 ESPP”) is measured based on grant date at fair value using the Black-Scholes option-pricing model. The model requires us to make a number of assumptions, including common stock fair value, expected volatility, expected term, risk-free interest rate and expected dividend yield. Stock-based compensation expense is recognized on a straight-line basis over the offering period.

We account for award forfeitures as they occur and classify stock-based compensation expense in our consolidated statements of operations and comprehensive loss in the same manner in which the award recipient’s salary or services costs are classified.

Off-Balance Sheet Arrangements

During the periods presented we did not have, nor do we currently have, any off-balance sheet arrangements as defined in the rules and regulations of the Securities and Exchange Commission (“SEC”).

JOBS Act Transition Period and Smaller Reporting Company Status

We are an “emerging growth company” as defined in the JOBS Act. Under the JOBS Act, an emerging growth company can take advantage of the extended transition period for complying with new or revised accounting standards and delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. We have elected to avail ourselves of this exemption from complying with new or revised accounting standards and, therefore, will not be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies. As a result, our financial statements may not be comparable to companies that comply with new or revised accounting pronouncements as of public company effective dates.

Subject to certain conditions, as an emerging growth company, we may rely on certain of these exemptions, including without limitation exemptions to the requirements for (i) providing an auditor’s attestation report on our system of internal controls over financial reporting pursuant to Section 404(b) of the Sarbanes-Oxley Act and (ii) complying with any requirement that may be adopted by the Public Company Accounting Oversight Board regarding mandatory audit firm rotation or a supplement to the auditor’s report providing additional information about the audit and the financial statements, known as the auditor discussion and analysis. We will remain an emerging growth company until the earlier to occur of (a) the last day of the fiscal year (A) following the fifth anniversary of the completion of our IPO, (B) in which we have total annual gross revenues of at least $1.235 billion or (C) in which we are deemed to be a “large accelerated filer” under the rules of the SEC, which means the market value of our common stock and non- voting common stock that is held by non-affiliates exceeds $700.0 million as of the prior June 30th, or (b) the date on which we have issued more than $1.0 billion in non-convertible debt during the prior three-year period.

We are also a “smaller reporting company,” as defined in Rule 12b-2 of the Exchange Act, meaning that the market value of our common stock and non-voting common stock held by non-affiliates was less than $250.0 million as of June 30, 2025. We may continue to be a smaller reporting company if either (i) the market value of our common stock and non-voting common stock held by non-affiliates is less than $250.0 million measured on the last business day of our second fiscal quarter or (ii) our annual revenue is less than $100.0 million during the most recently completed fiscal year and the market value of our common stock and non-voting common stock held by non-affiliates is less than $700.0 million measured on the last business day of our second fiscal quarter. If we are a smaller reporting company at the time we cease to be an emerging growth company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company we may choose to present only the two most recent fiscal years of audited consolidated financial statements in our Annual Report on Form 10-K and, similar to emerging growth companies, smaller reporting companies have reduced disclosure obligations regarding executive compensation.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Interest Rate Risk

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The primary objectives of our investment activities are to ensure liquidity and to preserve capital. We are exposed to market risks related to changes in interest rates of our cash equivalents and marketable securities. However, due to the nature of these cash equivalents and marketable securities, we do not believe that a hypothetical 10% increase or decrease in interest rates during any of the periods presented would have had a material effect on our consolidated financial statements included in Part II, Item 8 of this Annual Report on Form 10-K.

Foreign Currency Exchange Risk

All of our employees and our operations are currently located in the United States, and our expenses are generally denominated in U.S. dollars. However, we do utilize certain CRO and CMO vendors outside of the United States for our clinical trials and product development and manufacturing. As such, our expenses are denominated in both U.S. dollars and foreign currencies. Therefore, our operations are and will continue to be subject to fluctuations in foreign currency exchange rates. To date, foreign currency transaction gains and losses have not been material to our consolidated financial statements, and we have not had a formal hedging program with respect to foreign currency. We do not believe that a hypothetical 10% increase or decrease in exchange rates during any of the periods presented would have had a material effect on our consolidated financial statements included in Part II, Item 8 of this Annual Report on Form 10-K.

Effects of Inflation

Inflation generally affects us by increasing our cost of labor and research and development costs. We do not believe that inflation had a material effect on our business, results of operations, or financial condition, or on our consolidated financial statements included in Part II, Item 8 of this Annual Report on Form 10-K.

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Item 8. Financial Statements and Supplementary Data

ALUMIS INC.

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

​ ​ Page

Report of Independent Registered Public Accounting Firm (PCAOB ID 238) ​ ​ 119

Consolidated Balance Sheets ​ 120

Consolidated Statements of Operations and Comprehensive Loss ​ 121

Consolidated Statements of Cash Flows ​ 123

Notes to Consolidated Financial Statements ​ 124

​

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Report of Independent Registered Public Accounting Firm

To the Board of Directors and Stockholders of Alumis Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Alumis Inc. and its subsidiaries (the “Company”) as of December 31, 2025 and 2024, and the related consolidated statements of operations and comprehensive loss, of redeemable convertible preferred stock and stockholders’ equity (deficit) and of cash flows for the years then ended, including the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for the years then ended in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s consolidated financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits of these consolidated financial statements in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

/s/ PricewaterhouseCoopers LLP

San Jose, California

March 19, 2026

We have served as the Company’s auditor since 2022.

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ALUMIS INC.

CONSOLIDATED BALANCE SHEETS

​ ​ ​ ​ ​ ​ ​

​ ​ ​ ​ December 31, ​ ​ ​ December 31,

(in thousands, except share and per share amounts) ​ 2025 ​ 2024

Assets ​ ​ ​ ​

Current assets: ​ ​ ​ ​

Restricted cash ​ 82 ​ —

Research and development prepaid expenses ​ 2,909 ​ 13,424

Other prepaid expenses and current assets ​ 6,740 ​ 4,501

Restricted cash, non-current ​ 1,301 ​ 1,106

Intangible assets ​ ​ 50,959 ​ ​ —

Operating lease right-of-use assets, net ​ 16,971 ​ 12,723

Other assets, non-current ​ 6,287 ​ 7

Liabilities and Stockholders’ Equity ​ ​ ​ ​

Current liabilities: ​ ​ ​ ​

Research and development accrued expenses ​ 34,781 ​ 29,149

Deferred revenue, current ​ ​ 1,458 ​ ​ —

Other accrued expenses and current liabilities ​ 22,303 ​ 10,580

Operating lease liabilities, current ​ 4,670 ​ 1,557

Operating lease liabilities, non-current ​ 32,244 ​ 29,165

Deferred revenue, non-current ​ ​ 2,611 ​ ​ —

Deferred tax liability ​ ​ 2,140 ​ ​ —

Share repurchase liability ​ ​ 123 ​ ​ 813

Other liabilities, non-current ​ 207 ​ —

Commitments and contingencies (Note 9) ​ ​ ​ ​

Stockholders’ equity: ​ ​ ​ ​

Accumulated other comprehensive income (loss) ​ 188 ​ 40

Total liabilities and stockholders’ equity ​ $ 411,940 ​ $ 340,992

​

The accompanying notes are an integral part of these consolidated financial statements.

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ALUMIS INC.

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

​

​ ​ ​ ​ ​ ​ ​ ​

​ ​ ​ ​ Year Ended December 31, ​

(in thousands, except share and per share amounts) ​ ​ ​ 2025 ​ ​ ​ 2024 ​

Revenue: ​ ​ ​ ​ ​ ​ ​

License revenue ​ $ 17,389 ​ $ — ​

Collaboration revenue ​ ​ 6,661 ​ ​ — ​

Total revenue ​ ​ 24,050 ​ ​ — ​

Operating expenses: ​ ​ ​ ​ ​ ​ ​

General and administrative expenses ​ ​ 91,856 ​ ​ 35,200 ​

Other income (expense): ​ ​ ​ ​ ​

Gain on bargain purchase ​ 187,907 ​ — ​

Change in fair value of derivative liability ​ — ​ (5,406) ​

Other income (expenses), net ​ (169) ​ (93) ​

Total other income (expense), net ​ 201,918 ​ 6,521 ​

Income tax benefit ​ ​ 8,561 ​ ​ — ​

Other comprehensive income (loss): ​ ​ ​ ​ ​

Unrealized gain (loss) on marketable securities, net ​ 148 ​ 38 ​

​

The accompanying notes are an integral part of these consolidated financial statements.

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ALUMIS INC.

CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS’ EQUITY (DEFICIT)

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

​ ​ Redeemable ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ ​

​ Convertible ​ ​ ​ ​ ​ ​ Additional Other ​ ​ Total

Vesting of early exercised stock options — ​ — ​ — ​ — ​ 1,154 ​ — ​ — ​ 1,154

Other comprehensive income (loss), net — ​ — ​ — ​ — ​ — ​ 38 ​ — ​ 38

Vesting of early exercised stock options — ​ — ​ — ​ — ​ 671 ​ — ​ — ​ 671

Vesting of restricted shares of common stock — ​ — ​ — ​ — ​ 2 ​ — ​ — ​ 2

Stock-based compensation expense — ​ — ​ — ​ — ​ 43,524 ​ — ​ — ​ 43,524

Other comprehensive income (loss), net — ​ — ​ — ​ — ​ — ​ 148 ​ — ​ 148

​

The accompanying notes are an integral part of these consolidated financial statements.

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ALUMIS INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

​

​ ​ ​ ​ ​ ​ ​

​ ​ ​ ​ Year Ended December 31,

Cash flows from operating activities ​ ​ ​ ​

Net accretion of discounts on marketable securities ​ (5,298) ​ (3,685)

Depreciation and amortization ​ 3,496 ​ 3,152

Non-cash lease expense ​ 1,701 ​ 60

Loss on disposal of fixed assets ​ — ​ 5

Change in fair value of derivative liability ​ — ​ 5,406

Impairment of long-lived assets ​ ​ 529 ​ ​ —

Changes in operating assets and liabilities: ​ ​ ​ ​

Research and development prepaid expenses ​ 11,473 ​ (10,763)

Other prepaid expenses and other assets ​ 17,229 ​ (2,870)

Other assets, non-current ​ ​ (5,535) ​ ​ —

Deferred revenue ​ ​ 4,069 ​ ​ —

Research and development accrued expenses ​ 2,087 ​ 18,203

Other accrued expenses and current liabilities ​ 6,036 ​ 3,542

Operating lease liabilities ​ ​ (3,212) ​ ​ (1,858)

Other liabilities, non-current ​ ​ 207 ​ ​ —

Deferred tax liability ​ (8,561) ​ —

Net cash used in operating activities ​ (369,523) ​ (255,078)

Cash flows from investing activities ​ ​ ​ ​

Purchases of property and equipment ​ ​ (653) ​ ​ (1,732)

Net cash provided by (used in) investing activities ​ 287,877 ​ (113,790)

Cash flows from financing activities ​ ​ ​ ​

Proceeds from a private placement transaction ​ ​ — ​ ​ 40,000

Proceeds from issuance of common stock under the 2024 ESPP ​ ​ 1,595 ​ ​ —

Net cash provided by financing activities ​ 2,067 ​ 492,367

Supplemental disclosures: ​ ​ ​ ​

​ ​ ​ ​ ​ ​ ​

Reconciliation of cash, cash equivalents and restricted cash: ​ ​ ​ ​

Restricted cash ​ 82 ​ —

Restricted cash, non-current ​ 1,301 ​ 1,106

Total cash, cash equivalents and restricted cash ​ $ 91,053 ​ $ 170,632

​

The accompanying notes are an integral part of these consolidated financial statements.

​

​

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1.Organization and Nature of the Business

Organization and Business

Alumis Inc. (the “Company”) is a clinical stage biopharmaceutical company focused on identifying, acquiring, and accelerating the development and commercialization of transformative medicines for autoimmune disorders. The Company leverages its proprietary precision data analytics platform, biological insights, and a team of experts with deep experience in precision medicine drug discovery, development, and immunology, in its mission to create medicines that significantly improve the lives of patients by replacing broad immunosuppression with targeted therapies.

The Company was founded on January 29, 2021, as a Delaware corporation under the name FL2021-001, Inc. FL2021-001, Inc.’s name was changed to Esker Therapeutics, Inc. on March 8, 2021, and to Alumis Inc. on January 6, 2022. The Company is headquartered in South San Francisco, California.

As of December 31, 2023, the Company had two wholly owned subsidiaries, FronThera U.S. Holdings, Inc. and FronThera U.S. Pharmaceuticals LLC. FronThera U.S. Holdings, Inc. was dissolved on April 8, 2024 and FronThera U.S. Pharmaceuticals LLC was dissolved on March 14, 2024. These subsidiaries did not have operations during the year ended December 31, 2024.

As of December 31, 2025, the Company had two wholly owned subsidiaries, ACELYRIN, Inc. (“ACELYRIN”), a Delaware corporation incorporated on July 27, 2020 and its wholly owned subsidiary, WH2, LLC. Arrow Merger Sub, Inc. (“Merger Sub”), the Company’s wholly owned subsidiary incorporated in January 2025, was merged with and into ACELYRIN in May 2025.

Reverse Stock Split

On June 19, 2024, the board of directors approved, and on June 20, 2024, the Company effected, a reverse stock split of the shares of the Company’s outstanding common stock at a ratio of 1-for-4.675 (the “Reverse Stock Split”). The number of authorized shares and par value per share were not adjusted as a result of the Reverse Stock Split. All references to shares, options to purchase common stock, share amounts, per share amounts, and related information contained in the consolidated financial statements have been retrospectively adjusted to reflect the effect of the Reverse Stock Split for all periods presented. The shares of common stock underlying outstanding stock options and other equity instruments were proportionately reduced and the respective exercise prices, if applicable, were proportionately increased in accordance with the terms of the agreements governing such securities. In addition, the conversion ratios for each series of the Company’s redeemable convertible preferred stock, which were automatically convertible into shares of common stock upon the closing of the Company’s IPO of common stock, were proportionally adjusted.

IPO and Concurrent Private Placement

On July 1, 2024, the Company completed its IPO, pursuant to which it issued and sold 13,125,000 shares of its common stock at $16.00 price per share to the public. Net proceeds from the IPO were $193.3 million, after deducting underwriting discounts and commissions and other offering costs totaling $16.7 million. On July 17, 2024, in connection with the IPO, an existing investor and a holder of more than 5% of the Company’s capital stock, purchased an additional 2,500,000 shares of the Company’s common stock at the IPO price per share for total gross and net proceeds of $40.0 million in the Concurrent Private Placement.

Immediately prior to the closing of the IPO on July 1, 2024, all of the shares of the Company’s redeemable convertible preferred stock then outstanding converted into 28,855,656 shares of Class A common stock and 7,184,908 shares of Class B common stock at a 1-for-4.675 conversion ratio (the “Preferred Stock Conversion”). All outstanding Class A common stock shares and all outstanding Class B common stock shares were redesignated immediately thereafter into the same number of shares of voting common stock and non-voting common stock, respectively. Unless the context otherwise requires a different meaning, all references to “common stock” in these notes refers to the Company’s voting common

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stock and non-voting common stock combined.

ACELYRIN Merger

On February 6, 2025, the Company entered into an Agreement and Plan of Merger, and, on April 20, 2025, the Company entered into an Amendment to Agreement and Plan of Merger (collectively the “Merger Agreement”) with ACELYRIN and Merger Sub, a Delaware corporation and a direct wholly owned subsidiary of the Company. Under the terms of the Merger Agreement, Merger Sub merged with and into ACELYRIN, with ACELYRIN continuing as a direct wholly owned subsidiary of the Company (the “ACELYRIN Merger”). The Merger Agreement was approved by the disinterested directors on the Company’s board of directors and the board of directors of ACELYRIN and was approved by the stockholders of each company on May 13, 2025. On May 21, 2025, the Company completed the ACELYRIN Merger with ACELYRIN for a purchase consideration of approximately $238.1 million that included the issuance of 48,653,549 shares of the Company’s common stock and the fair value of replacement awards attributable to pre-combination services, to acquire net assets with a fair value of approximately $426.0 million. See Note 3 for additional information.

Public Offering of Common Stock

On January 7, 2026, the Company entered into the Underwriting Agreement with the Underwriters, relating to the issuance and sale in a public offering of 17,650,000 shares of the Company’s common stock at a price of $17.00 per share. In addition, the Company granted the Underwriters an option, exercisable for 30 days, to purchase up to 2,647,500 additional shares of common stock at the public offering price, less the underwriting discounts and commissions, which was exercised in full on January 8, 2026. On January 9, 2026, the offering closed and the Company received net proceeds of $324.4 million, after deducting underwriting discounts and commissions.

The offering was made pursuant to a shelf registration statement on Form S-3 (File No. 333-288510) that was filed with the SEC on July 3, 2025 and declared effective by the SEC on August 19, 2025, and related prospectus and prospectus supplement thereunder.

Liquidity

The Company has incurred negative operating cash flows and significant losses from operations since its inception. For the years ended December 31, 2025 and 2024, the Company incurred net losses of $243.3 million and $294.2 million, respectively. Cash used in operating activities was $369.5 million and $255.1 million for the years ended December 31, 2025 and 2024, respectively. As of December 31, 2025, the Company had an accumulated deficit of $901.9 million.

The Company has historically funded its operations primarily through the issuance of common stock, including in connection with the ACELYRIN Merger, its IPO and Concurrent Private Placement, the issuance of redeemable convertible preferred stock and convertible promissory notes in private placements, payments received under the Kaken Collaboration Agreement and, most recently, the public offering of common stock which closed on January 9, 2026. The Company expects to continue to incur substantial losses for the foreseeable future, and its ability to achieve and sustain profitability will depend on the successful development, approval, and commercialization of any product candidates it may develop, and on the achievement of sufficient revenue to support its cost structure. The Company may never achieve profitability and, unless and until it does, it will need to continue to raise additional capital. The Company believes that, based on its current operating plan, its existing cash, cash equivalents and marketable securities of $308.5 million as of December 31, 2025, as well as net proceeds of $324.4 million, after deducting underwriting discounts and commissions from the public offering of common stock, which closed on January 9, 2026, will be sufficient to meet its operating and capital requirements for at least 12 months from the date of issuance of these consolidated financial statements.

The Company will need to raise significant additional capital to fund ongoing research and development activities and maintain future operations. The Company’s management continuously monitors and, where necessary, may reduce its operating expenses in response to its clinical development progress and its ability and need to raise additional capital

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through a combination of public and private equity, debt financings, strategic alliances and licensing arrangements. For example, should any of the Company’s ongoing trials not meet its clinical development objectives, the Company may scale back or discontinue related activities and reallocate its working capital to extend its ability to meet its operating and capital requirements. The Company’s ability to access capital when needed is not assured and, if capital is not available to the Company when, and in the amounts, needed, on the terms which are favorable, the Company could be required to delay, scale back, or abandon some or all of its planned development programs and other operations, which could materially harm the Company’s business, financial condition and results of operations.

​

2.Summary of Significant Accounting Policies and Basis of Presentation

Basis of Presentation

The accompanying consolidated financial statements and accompanying notes have been prepared in accordance with U.S. GAAP. The Company’s consolidated financial statements include the accounts of its subsidiaries, and all intercompany transactions were eliminated. The Company’s consolidated financial statements as of and for the year ended December 31, 2025, include the accounts of its subsidiaries ACELYRIN and WH2, LLC after the closing of the ACELYRIN Merger, and the accounts of Merger Sub from its incorporation in January 2025 until the ACELYRIN Merger. WH2, LLC has not had any operations or any balances since the closing of the ACELYRIN Merger. The Company’s consolidated financial statements as of and for the year ended December 31, 2024, included the accounts of FronThera U.S. Holdings, Inc. and FronThera U.S. Pharmaceuticals LLC, two wholly owned subsidiaries, prior to their dissolution.

Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the ASC and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period.

On an ongoing basis, the Company evaluates estimates and assumptions, including but not limited to those related to research and development expenses, valuation of acquired IPR&D intangible assets, revenue recognition, and stock-based compensation expense. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ materially from those estimates.

Segment and Geographical Information

The Company operates and manages its business as one reportable and operating segment, which is the business of researching and developing medicines for autoimmune disorders. The chief executive officer, who is the chief operating decision maker (“CODM”), reviews financial information on an aggregate basis for purposes of allocating resources and evaluating financial performance (see Note 16 for additional information). All of the Company’s long-lived assets are located in the United States.

Concentration of Credit Risk

Financial instruments, which potentially subject the Company to concentration of credit risk, consist primarily of cash and cash equivalents, investments in marketable securities, accounts receivable and restricted cash. The Company maintains bank deposits in federally insured financial institutions and certain of these deposits exceed federally insured limits. To date, the Company has not experienced any losses on its deposits of cash and periodically evaluates the creditworthiness of the financial institutions at which its bank deposits are maintained.

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The Company also invests in money market funds, U.S. Treasury obligations, commercial paper, corporate debt obligations, supranational debt obligations, government development bank obligations and Federal agency obligations, which can be subject to certain credit risks. The Company mitigates the risks by limiting its exposure to any one issuer and monitoring the ongoing creditworthiness of the financial institutions and issuers. The Company has not experienced any loss of principal on its financial instruments.

The Company considers a customer to be significant when revenues from that customer represent 10% or more of total revenues. All of the Company’s revenues are currently earned under its license and collaboration agreement with Kaken. As a result, the Company is subject to customer concentration risk. To date, the Company has not incurred any credit losses in connection with the Kaken Collaboration Agreement.

Risks and Uncertainties

The Company is subject to certain risks and uncertainties, including, but not limited to, changes in any of the following areas that the Company believes could have a material adverse effect on the future financial position or results of operations: the Company’s ability to advance the development of its proprietary precision data analytics platform, timing and ability to advance its product candidates through preclinical and clinical development; costs and timelines associated with the manufacturing of clinical supplies; regulatory approval, market acceptance of, and reimbursement for, any product candidates the Company may develop; performance of third-party vendors; competition from pharmaceutical or other biotechnology companies with greater financial resources or expertise; protection of intellectual property; litigation or claims against the Company based on intellectual property or other factors; and its ability to attract and retain employees necessary to support its growth.

The Company’s business and results of operations may be affected by worldwide economic conditions, which may continue to be impacted by global macroeconomic challenges and uncertainty in the markets, including international trade policies and tariffs, severely diminished liquidity and credit availability, rising inflation and monetary supply shifts, rising interest rates, labor shortages, declines in consumer confidence, declines in economic growth, increases in unemployment rates, recession risks and uncertainty about economic and geopolitical stability (for example, related to the evolving U.S. and ex-U.S. tariff landscape). These worldwide economic conditions have continued throughout 2025 and may negatively impact the Company’s business, financial position and results of operations.

Business Acquisitions, Including Intangible Assets, Goodwill and Contingent Consideration

The Company accounts for business combinations, as defined in ASC Topic 805, Business Combinations, using the acquisition method of accounting, which generally requires that assets acquired, including IPR&D intangible assets, and liabilities assumed, be recorded at fair value on the consolidated balance sheet as of the acquisition date. The excess of the fair value of the purchase consideration over the fair value of net assets acquired, if any, is recorded as goodwill on the consolidated balance sheet. The excess of the fair value of net assets acquired over the fair value of the purchase consideration, if any, represents negative goodwill, or a gain on bargain purchase, which is recognized in the consolidated statement of operations as of the date of the acquisition.

Calculating the fair value of assets acquired and liabilities assumed requires the Company to make significant estimates and assumptions. As a result, the Company may record adjustments to the fair values within the measurement period, which may be up to one year from the acquisition date, with the corresponding offset to goodwill or a gain on bargain purchase.

Transaction costs associated with business combinations are expensed as they are incurred.

Intangible assets related to IPR&D projects acquired are considered to be indefinite-lived until abandonment or completion of the associated R&D efforts, which generally occurs when regulatory approval is obtained. Goodwill and indefinite-lived intangible assets are not amortized and, instead, are tested for impairment annually, in the fourth quarter, or more frequently if events or changes in circumstances indicate that it is more likely than not that the assets are impaired as

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required by ASC 350 Intangibles - Goodwill and Other. Such events and circumstances may include a significant change in the Company’s business climate, economic and industry trends, legal factors, negative operating performance indicators, significant competition or changes in strategy. The Company performs testing of indefinite-lived intangible assets, other than goodwill, at the asset group level using a discounted cash flow model. If the carrying value exceeds the fair value, an impairment loss is recorded for that excess. The Company would also be required to reduce the carrying amounts of the related assets on its consolidated balance sheet. Determining the fair value of an indefinite-lived intangible asset group requires the application of judgment and involves the use of significant estimates and assumptions, including projections of future cash flows, which include estimated revenues, costs and probabilities of achieving technical and regulatory milestones, and discount rates, among other factors. The Company bases its fair value estimates on assumptions it believes to be reasonable, but which are unpredictable and inherently uncertain. Actual future results may differ from the estimates. Development costs incurred after an acquisition are expensed as they are incurred.

Intangible assets with finite useful lives, which include completed IPR&D projects, are amortized over their estimated useful lives, primarily on a straight-line basis, and are also periodically reviewed for changes in facts or circumstances that may result in an impairment or in a reduction to the estimated useful life of the asset.

In determining the initial fair value of an intangible asset, or when quantitative analysis is required to determine any impairment, the Company usually uses an income approach that discounts expected future cash flows to present value using a discount rate that is based on the estimated weighted-average cost of capital for comparable companies and represents the rate that market participants would use to value the intangible asset. These cash flow models require the use of Level 3 fair value measurements and inputs, including estimated revenues, costs and probabilities of technical and regulatory milestones, among other factors.

If the Company is required to pay future consideration that is contingent upon the achievement of specified development, regulatory approval or sales-based milestone events, then the estimated fair value of contingent consideration liabilities is recognized in the consolidated balance sheet as of the date of the acquisition. Each reporting period thereafter, the Company revalues these obligations and records increases or decreases in their fair value on the consolidated statements of operations until such time that the payment is made or obligations expire. See Note 3 for additional information.

Collaboration Arrangements and Revenue Recognition

The Company earns revenue from collaboration agreements that allow collaborators to develop, manufacture and commercialize product candidates. Arrangements with collaborators may include intellectual property licenses, research and development services, manufacturing services for clinical and commercial supply and participation in joint steering committees. At the inception of an agreement, the Company evaluates if an agreement is a collaborative arrangement within the scope of ASC 808, Collaborative Arrangements (“ASC 808”). For collaborative arrangements that fall within the scope of ASC 808, the Company first determines which elements of the collaboration are deemed to be a performance obligation with a customer within the scope of ASC 606. For elements of collaboration arrangements that are accounted for pursuant to ASC 808 and are not subject to the guidance in ASC 606, the Company applies the revenue recognition model under ASC 606 or other guidance, as deemed appropriate.

Under ASC 606, the Company recognizes revenue in an amount that reflects the consideration that the Company expects to receive in exchange for those goods or services when its collaborator, or customer, obtains control of promised goods or services. The Company follows a five-step approach: (i) identify the contract with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations and (v) recognize revenue when (or as) the customer obtains control of the product or service.

The Company assesses the goods or services promised within the contract to determine whether each promised good or service is a performance obligation. Performance obligations are promises in a contract to transfer a distinct good or service to the customer that (i) the customer can benefit from on its own or together with other readily available resources and (ii) are separately identifiable from other promises in the contract. Goods or services that are not individually distinct performance obligations are combined with other promised goods or services until such combined group of promises meet

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the requirements of a performance obligation.

The Company determines the transaction price based on the amount of consideration the Company is entitled to receive in exchange for the transfer of control of a product or a service to the customer. Consideration may be fixed, variable, or a combination of both. Payments to the Company under these arrangements typically include one or more of the following: non-refundable upfront payments, reimbursement for research services, payments for clinical supplies, research, development or regulatory milestone payments, profit-sharing arrangements, and royalty and commercial sales milestone payments. Variable consideration, such as performance-based milestones, are included in the total consideration if the Company expects to receive such consideration and if it is probable that the inclusion of the variable consideration will not result in a significant reversal in the cumulative amount of revenue recognized under the arrangement. The Company accounts for cost reimbursements included in the transaction price using the expected value method. The Company excludes sales-based royalty and milestone payments from the total consideration it expects to receive until the underlying sales occur because the license to its intellectual property is deemed to be the predominant item to which the royalties or milestones relate as it is the primary driver of value in the collaboration arrangements.

The Company then allocates the transaction price to each distinct performance obligation based on the relative standalone selling price. Key assumptions to determine the standalone selling price may include forecasted revenues, development timelines, probabilities of technical and regulatory success, and the expected level of effort for research and development services. The Company recognizes revenue associated with each performance obligation as the control over the promised goods or services transfer to its collaborators which occurs either at a point in time or over time. If control transfers over time, revenue is recognized by using a method of measuring progress that best depicts the transfer of goods or services. The Company evaluates the measure of progress and related inputs each reporting period and any resulting adjustments to revenue are recorded on a cumulative catch-up basis. Consideration allocated to options that include material rights is deferred until the options are exercised or expire.

The Company records amounts as accounts receivable when the right to consideration is deemed unconditional. Consideration received that does not meet the requirements to satisfy ASC 606 revenue recognition criteria is recorded as deferred revenue in the consolidated balance sheets, classified as either current (less than 12 months) or non-current (more than 12 months) deferred revenue based on the Company’s best estimate of when such revenue will be recognized. See Note 7 for additional information.

Cash and Cash Equivalents

The Company considers all highly liquid investments purchased with an original maturity of three months or less to be cash equivalents.

Restricted Cash

Restricted cash represents security deposits in the form of letters of credit issued in connection with the Company’s leases (see Note 6 for additional information).

Marketable Securities

Marketable securities may consist of money market funds, U.S. Treasury obligations, commercial paper, corporate debt obligations, supranational debt obligations, government development bank obligations and Federal agency obligations with original maturities of more than three months at the time of purchase. As the Company’s entire investment portfolio is considered available for use in current operations, the Company classifies all marketable securities as available-for-sale and as current assets, even though the stated maturity may be more than one year from the current balance sheet date. Marketable securities are carried at fair value, with the change in fair value reported as unrealized gains or losses in accumulated other comprehensive income (loss), which is a separate component of stockholders’ equity (deficit) in the consolidated balance sheets.

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The amortized cost of marketable securities is adjusted for amortization of premiums and accretion of discounts to maturity, which is included in interest income in the consolidated statements of operations and comprehensive loss. Realized gains and losses on the sale of securities are determined by specific identification of each security’s cost basis. The Company regularly reviews its investment portfolio to determine if any security is impaired, which would require it to record an allowance for credit losses or an impairment charge in the period any such determination is made. In making this judgment, the Company evaluates, among other things, the extent to which the fair value of a security is less than its amortized cost, its intent to sell or whether it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis, the financial condition of the issuer and any changes thereto, and, as necessary, the portion of a decline in fair value that is credit-related. This assessment could change in the future due to new developments or changes in assumptions related to any particular security. Realized gains and losses, allowances for credit losses and impairments on available-for-sale marketable securities, if any, are recorded in the consolidated statements of operations and comprehensive loss.

Fair Value Measurement

Fair value is defined 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. The carrying amounts of prepaid expenses, other current assets, accounts payable, accrued expenses and other liabilities approximate fair value due to their short-term maturities. Financial instruments, such as money market funds, marketable securities and derivative liabilities are measured at fair value at each reporting date (see Note 4 for additional information).

Recoverable Value-Added Tax

The Company conducts clinical trials in several European and Asian countries that can result in value-added tax (“VAT”) assessments based on the transfer of products across borders including production, packaging and distribution of clinical materials. VAT is a national tax that is levied at each stage of production and can vary by jurisdiction. When a company is not VAT-registered in a country, VAT is due when goods enter a country and is not considered reclaimable. When the Company becomes VAT-registered and establishes a pattern of VAT recoverability from taxing authorities in a certain country, the Company will record aggregate balances recoverable in other prepaid expenses and current assets in the consolidated balance sheets. The Company reviews these balances on a regular basis and records valuation allowances on the amounts that are not expected to be recovered.

Deferred Offering Costs

Deferred offering costs, consisting of legal, accounting and other third-party fees directly relating to in-process equity financings or offerings are capitalized. Deferred offering costs are offset against offering proceeds upon the completion of the financing or the offering. In the event the financing or the offering is terminated or delayed, deferred offering costs are expensed immediately as a charge to general and administrative expenses in the consolidated statements of operations and comprehensive loss. As of December 31, 2025 and 2024, the Company had $0.4 million and zero deferred offering costs, respectively, in other assets, non-current in its consolidated balance sheets.

Property and Equipment, Net

Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation is calculated using the straight-line method over the estimated useful lives of assets. Costs for capital assets not yet placed into service are capitalized as construction-in-progress and depreciated once placed into service. Repair and maintenance costs that are not considered improvements and do not extend the useful life of property and equipment, are expensed as incurred. Improvements are capitalized as additions to property and equipment. Upon sale or retirement of assets, the costs and related accumulated depreciation are removed from the consolidated balance sheets and the resulting gain or loss is reflected within operating expenses in the consolidated statements of operations and comprehensive loss.

Asset Acquisitions and Acquired IPR&D Assets

The Company measures and recognizes asset acquisitions that are not deemed to be business combinations based on the

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cost to acquire the asset or group of assets, which includes transaction costs. The Company determines if the acquisition should be accounted for as an asset acquisition after considering whether substantially all of the fair value of the gross assets acquired is concentrated in a single asset or group of assets and whether the Company acquired a substantive process capable of significantly contributing to the Company’s ability to create outputs. Goodwill is not recognized in asset acquisitions. If acquired in-process technology assets, including licenses, know-how and patents are determined to not have an alternative future use, the cost is charged to research and development expenses at the acquisition date.

The Company accounts for contingent consideration identified in an asset acquisition that does not meet the definition of a derivative under ASC 815, Derivatives and Hedging, when the payment becomes probable and reasonably estimable. Such amounts are expensed or capitalized based on the nature of the associated asset at the date the related contingency is recognized.

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Leases

The Company determines whether an arrangement is or contains a lease at the inception of the arrangement and whether such a lease should be classified as a financing lease or operating lease at the commencement date of the lease. Leases with a term greater than one year are classified as operating lease right-of-use assets, net and operating lease liabilities, current and non-current in the consolidated balance sheets. The Company elected not to recognize the right-of-use assets and lease liabilities for leases with lease terms of one year or less (short-term leases). Lease liabilities and their corresponding right-of-use assets are recorded based on the present value of lease payments over the lease term. The Company considers the lease term to be the noncancelable period that it has the right to use the underlying asset, together with any periods where it is reasonably certain it will exercise an option to extend (or not terminate) the lease. As the interest rate implicit in the Company’s lease contracts is not readily determinable, the Company utilizes its incremental borrowing rate to determine the present value of lease payments. The incremental borrowing rate is derived from information available at the lease commencement date and represents the rate of interest that a lessee would have to pay to borrow an amount equal to the lease payments on a collateralized basis over a similar term in a similar economic environment.

Rent expense for operating leases is recognized on a straight-line basis over the lease term. The Company has elected to not separate lease and non-lease components for its real estate leases and instead accounts for each separate lease component and the non-lease components associated with that lease component as a single lease component. Variable lease payments are recognized as incurred.

As of December 31, 2025 and 2024, the Company had no finance leases.

Impairment of Definite-Lived Long-Lived Assets

The Company regularly reviews the carrying value and estimated lives of all of its definite-lived long-lived assets, including property and equipment, and right-of-use assets to determine whether indicators of impairment may exist that warrant adjustments to carrying values or estimated useful lives. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset group to future undiscounted net cash flows expected to be generated by the asset or asset group. Should impairment exist, the impairment loss to be recognized is measured by the amount by which the carrying amount of the asset exceeds the projected discounted future net cash flows arising from the asset.

Derivative Liability

The Company may issue financial instruments, such as promissory notes, that include embedded derivatives, such as call options. Derivatives are accounted for under ASC 815, Derivatives and Hedging. The Company performs analysis of derivatives embedded in the financial instruments, and if any require bifurcation, accounts for these at fair value at the issuance date. A derivative liability is accounted for separately from the financial instrument at fair value on the issuance date and is remeasured each reporting period. The changes in the fair value of the derivative liability are included in change in fair value of derivative liability in the consolidated statements of operations and comprehensive loss.

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In March 2024, in connection with the Company’s redeemable convertible preferred stock financings, the Company issued options to purchase additional shares of redeemable convertible preferred stock at a specified price, which were accounted for as derivative liabilities. Changes in fair value of these derivative liabilities were included in the other income (loss) in the consolidated statement of operations and comprehensive loss for each reporting period until the derivatives were settled in May 2024 (see Note 4).

Redeemable Convertible Preferred Stock

The Company recorded redeemable convertible preferred stock at their respective fair values on the dates of issuance, net of offering costs. The redeemable convertible preferred stock was recorded outside of permanent equity because while it was not mandatory, redemption was contingent upon the occurrence of certain events considered not solely within the Company’s control. The Company did not adjust the carrying values of the redeemable convertible preferred stock to the liquidation preferences of such stock, because it was uncertain whether or when a deemed liquidation event would occur that would obligate the Company to pay the liquidation preferences to holders of redeemable convertible preferred stock. Subsequent adjustments to the carrying values to the liquidation preferences would be made only when it became probable that such a deemed liquidation event would occur. All redeemable convertible preferred stock outstanding was converted into common stock immediately prior to the closing of the IPO on July 1, 2024, and the Company had no outstanding redeemable convertible preferred stock outstanding as of December 31, 2025 and 2024.

Research and Development Expenses and Accruals

Research and development costs are expensed as incurred. Research and development costs consist primarily of costs associated with acquiring technology and intellectual property licenses that have no alternative future uses, costs incurred under in-license or assignment agreements, salaries and benefits of research and development personnel, costs related to research activities, preclinical studies, clinical trials, drug manufacturing, third-party professional research and development consulting services, and allocated overhead and facility-related expenses. Payments associated with licensing agreements to acquire exclusive licenses to develop, use, manufacture and commercialize products that have not reached technological feasibility and do not have alternate future use will also be expensed as incurred.

The Company records accrued liabilities for estimated costs of its research and development activities conducted by third-party service providers. The Company accrues these costs based on factors such as estimates of the work completed and in accordance with the third-party service agreements. 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 estimates. To date, the Company has not experienced any material differences between accrued costs and actual costs incurred.

Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. The prepaid amounts are expensed as the related goods are delivered or the services are performed and classified as current or non-current prepaid expenses and other assets.

The Company makes payments in connection with clinical trials to CMOs that manufacture the materials for its product candidates and to CROs and clinical trial sites that conduct and manage the Company’s clinical trials. 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. Generally, these agreements set forth the scope of work to be performed at a fixed fee, unit price or on a time and materials basis. The Company makes estimates of accrued research and development expenses as of each balance sheet date based on facts and circumstances known at that time. The Company periodically confirms the accuracy of its estimates with the service providers and makes adjustments, if necessary. Research and development accruals are estimated based on the level of services performed, progress of the studies, including the phase or completion of events, and contracted costs. The estimated costs of research and development services provided, but not yet invoiced, are included in accrued expenses in the consolidated balance sheets. If the actual timing of the performance of services or the level of effort varies from the original estimates, the Company will adjust the accrual accordingly.

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Comprehensive Loss

Comprehensive loss represents all changes in stockholders’ deficit except those resulting from distributions to stockholders. The Company’s other comprehensive income (loss) for the years ended December 31, 2025 and 2024 consisted of unrealized gain (loss) on marketable securities, net of taxes.

Patent Costs

All patent-related costs incurred in connection with filing and prosecuting patent applications are expensed as incurred due to the uncertainty about the recovery of the expenditure. Amounts incurred are classified as general and administrative expenses in the consolidated statements of operations and comprehensive loss.

Stock-Based Compensation Expense

The Company accounts for stock-based compensation expense in accordance with ASC 718. The Company grants stock-based awards to employees, directors and non-employee consultants in the form of stock options and RSUs to purchase shares of its common stock. The Company measures stock options granted with service-based vesting based on the fair value of the award on the grant date using the Black-Scholes option-pricing model. The model requires management to make a number of assumptions, including common stock fair value, expected volatility, expected term, risk-free interest rate and expected dividend yield. The Company expenses the fair value of its stock-based compensation awards on a straight-line basis over the requisite service period, which is the period in which the related services are received.

The Company has also granted stock options with graded vesting based on market, service and performance conditions. At the grant date, the fair value of these stock options was estimated using a Monte Carlo simulation model, which uses a distribution of potential outcomes over the vesting period. The assumptions utilized in the calculation included the Company’s expected common stock price, expected volatility, risk-free rate and expected term. Stock-based compensation expense for these awards is recognized on a straight-line basis over the requisite service period, which is the longer of the explicit service period of the service condition and the derived service period of the market condition, as determined for each separately vesting portion of the awards as if each award was, in substance, multiple awards.

Stock-based compensation expense related to stock purchase rights under the Company’s 2024 ESPP is measured based on grant date at fair value using the Black-Scholes option-pricing model. The model requires management to make a number of assumptions, including common stock fair value, expected volatility, expected term, risk-free interest rate and expected dividend yield. Stock-based compensation expense is recognized on a straight-line basis over the offering period

The Company accounts for award forfeitures as they occur and classifies stock-based compensation expense in its consolidated statements of operations and comprehensive loss in the same manner in which the award recipient’s salary or services costs are classified.

Income Taxes

The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company’s tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes.

The Company assesses the likelihood of deferred tax assets being realized. It provides a valuation allowance when it is more likely than not that some portion or all of a deferred tax asset 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.

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The Company recognizes the tax benefit from an uncertain tax position if it is more likely than not that the tax position will be sustained upon examination by the tax authorities, based on the merits of the position. The Company’s policy is to recognize interest and penalties related to the underpayment of income taxes as a component of income tax expense or benefit. To date, there have been no interest or penalties incurred in relation to unrecognized tax benefits.

Net Loss Per Share Attributable to Common Stockholders

Basic and diluted net loss per share attributable to common stockholders is presented in conformity with the two-class method required for participating securities. As such, net income is attributed to common stockholders and participating securities based on their participation rights. Prior to the IPO, under the two-class method, the net loss attributable to common stockholders was not allocated to the redeemable convertible preferred stock as the holders of the redeemable convertible preferred stock did not have a contractual obligation to share in the Company’s losses. Upon the IPO, the Company’s redeemable convertible preferred stock converted into either Class A or Class B common stock, and were immediately thereafter redesignated into voting and non-voting common stock, respectively, and therefore are included in the allocation of net loss attributable to common stockholders as they share in the Company’s losses. Voting and non-voting common stock participate in the Company’s losses equally. Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. Potentially dilutive securities include stock options and RSUs issued and outstanding, early exercised stock options, and unvested restricted common stock. As the Company has reported losses for all periods presented, all potentially dilutive securities are antidilutive and accordingly, basic net loss per share equals diluted net loss per share.

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. The Company qualifies as an “emerging growth company” as defined in the JOBS Act, and has elected not to “opt out” of the extended transition related to complying with new or revised accounting standards, which means that when a standard is issued or revised and it has different application dates for public and private companies, the Company will adopt the new or revised standard at the time private companies adopt the new or revised standard and will do so until such time that the Company either (i) irrevocably elects to “opt out” of such extended transition period or (ii) no longer qualifies as an emerging growth company. The Company may choose to early adopt any new or revised accounting standards whenever such early adoption is permitted for private companies.

Recently Adopted Accounting Pronouncements

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”), which requires the disclosure of specific categories in the rate reconciliation and greater disaggregation for income taxes paid. ASU 2023-09 is effective for annual periods beginning after December 15, 2024 for public entities and for fiscal years beginning after December 15, 2025 for all other entities, with early application permitted. ASU 2023-09 should be adopted prospectively with the option to be adopted retrospectively. The Company adopted this standard prospectively effective for the year ended December 31, 2025 and reflected the required annual income tax disclosures in the notes to its consolidated financial statements (see Note 15).

Recently Issued and Not Yet Adopted Accounting Pronouncements

In November 2024, the FASB issued ASU No. 2024-03, Disaggregation of Income Statement Expenses (Topic 220) (“ASU 2024-03”), requiring that public business entities disclose additional information about specific expense categories in the notes to financial statements at interim and annual reporting periods. The amendments of ASU 2024-03 are effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. The requirements of ASU 2024-03 may be applied either prospectively to financial statements issued for reporting periods after the effective date or retrospectively to any or all prior periods presented in the financial statements. The

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Company is currently evaluating the impact of adopting ASU 2024-03 on its consolidated financial statements and disclosures.

In December 2025, the FASB issued ASU No. 2025-11, Interim Reporting (Topic 270): Narrow-Scope Improvements (“ASU 2025-11”), which clarifies the form and content of interim financial statements, adds a comprehensive list of required interim disclosures, and provides a disclosure principle for condensed interim financial statements. ASU 2025-11 is effective for interim reporting periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted and, on adoption, can be applied either prospectively or retrospectively to any or all periods presented in the financial statements. The Company is currently evaluating the impact of the new standard on the Company's consolidated financial statements and related disclosures.

3.Acquisition

ACELYRIN Merger

The Company completed its acquisition of ACELYRIN on the Closing Date of May 21, 2025 and accounted for the transaction as an acquisition under ASC Topic 805, Business Combinations. ACELYRIN was a late-stage biopharma company focused on identifying, acquiring, and accelerating the development and commercialization of transformative medicines. ACELYRIN’s portfolio consisted of lonigutamab, a subcutaneously delivered, monoclonal antibody targeting IGF-1R for the potential treatment of Thyroid Eye Disease (“TED”). The ACELYRIN Merger strengthened the Company’s balance sheet and its cash position and added the lonigutamab product candidate to the Company’s development portfolio as of the Closing Date.

As of the Closing Date, the Company (i) issued 48,653,549 shares of its common stock in exchange for ACELYRIN’s issued and outstanding common stock shares and paid cash for fractional shares, (ii) assumed ACELYRIN’s stock options with an exercise price of $18.00 or less outstanding and unexercised immediately prior to the Closing Date, which are exercisable into 4,712,186 shares of the Company’s common stock, (iii) assumed ACELYRIN’s RSUs outstanding and unvested immediately prior to the Closing Date, which were converted into 1,323,905 of the Company’s RSUs, and (iv) assumed ACELYRIN’s performance RSUs outstanding and unvested immediately prior to the Closing Date, which were converted into 146,963 of the Company’s RSUs subject only to a service vesting condition.

Outstanding shares, stock options, RSUs and performance RSUs were exchanged at the exchange ratio of 0.4814 shares of the Company’s common stock for each share of ACELYRIN common stock (the “Exchange Ratio”). ACELYRIN’s outstanding and unexercised options with exercise prices more than $18.00 were cancelled. Exercise prices for the assumed options were determined as the product of the original exercise prices multiplied by the reciprocal of the Exchange Ratio. Converted ACELYRIN stock options and RSUs continue to vest in accordance with their original terms. Performance RSUs were deemed to have 100% satisfied their performance conditions and will vest in two equal installments on May 15 of calendar years 2026 and 2027, subject to the holder of the converted performance RSUs remaining in service with the Company or any of its subsidiaries on such date.

The purchase price consideration consists of the Company’s shares of common stock issued as of the Closing Date and the additional stock-based compensation related to the fair value of replacement awards attributable to pre-combination services, and is calculated as follows (in thousands, except share and per share amounts):

​ ​ ​ ​

Closing price per share of common stock as of Closing Date ​ $ 4.78

Consideration transferred for share exchange ​ $ 232,564

Total purchase price consideration ​ $ 238,077

​

The ACELYRIN Merger was accounted for as a business combination with the Company being treated as the accounting

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acquirer. Net assets acquired were recognized at their fair value as of the Closing Date of the ACELYRIN Merger. The Company recognized ACELYRIN Merger transaction costs of $14.7 million in general and administrative expenses in the consolidated statements of operations and comprehensive loss for the year ended December 31, 2025.

The following table presents the final purchase price allocation of the fair value of the net assets acquired and liabilities assumed as of the Closing Date (in thousands):

​

​ ​ ​ ​

Assets Acquired ​ ​

Cash and cash equivalents ​ $ 49,155

Restricted cash ​ 367

Marketable securities ​ 333,436

Research and development prepaid expenses ​ 958

Prepaid credit voucher for clinical manufacturing ​ ​ 11,376

Other prepaid expenses and current assets ​ 8,081

Restricted cash, non-current ​ 220

Property and equipment ​ 420

Intangible assets ​ ​ 50,959

Operating lease right-of-use assets ​ 4,349

Other assets, non-current ​ 744

Liabilities Assumed ​ ​

Accounts payable ​ $ (6,518)

Research and development accrued expenses ​ (3,546)

Other accrued expenses and current liabilities ​ (5,688)

Operating lease liabilities, current ​ (1,390)

Operating lease liabilities, non-current ​ (6,238)

Deferred tax liability ​ (10,701)

Total liabilities ​ (34,081)

Fair value of net assets ​ $ 425,984

Purchase consideration ​ ​ 238,077

Gain on bargain purchase ​ $ 187,907

​

The acquisition method requires, among other things, that assets acquired and liabilities assumed in a business combination be recognized at their fair values as of the Closing Date. Valuing certain components of the ACELYRIN Merger, primarily the acquired IPR&D intangible asset and a deferred tax liability required the Company to make significant estimates and assumptions. The valuation of assets acquired and liabilities assumed was finalized during the three months ended December 31, 2025, which did not result in any measurement period adjustments.

Intangible assets represent the acquired IPR&D intangible asset related to the acquired lonigutamab product candidate in development as of the Closing Date. The fair value of the acquired IPR&D intangible asset was calculated as $51.0 million using the multi-period excess earnings method, which is equal to the present value of the incremental after-tax cash flows attributable to that intangible asset, using a discount rate of 24.0% based on the best estimate of a market participant's after-tax weighted average cost of capital. Projected future cash flows were based on significant estimates, including estimated revenues, costs and probabilities of achieving technical and regulatory milestones, among other factors. The acquired IPR&D intangible asset is an indefinite-lived intangible asset and is subject to an annual impairment test. The Company performed a quantitative analysis for its annual impairment assessment of the acquired IPR&D intangible asset as of December 31, 2025. The quantitative analysis utilized a discounted cash flow model with assumptions that are considered level 3 inputs and concluded that the acquired IPR&D intangible asset had a fair value in excess of its carrying value as of December 31, 2025, and therefore no impairment was identified.

The Company acquired a prepaid credit voucher for clinical manufacturing issued by one of ACELYRIN’s contract

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manufacturers that will be applied towards payments of clinical product manufacturing invoices issued by the vendor. The remaining balance of $11.4 million as of the Closing Date was not adjusted from its carrying amount as its fair value approximated its carrying value as of this date.