VIR BIOTECHNOLOGY, INC., 10-Q filed on 5/8/2025
Quarterly Report
v3.25.1
Cover - shares
 3 Months Ended
Mar. 31, 2025
Apr. 30, 2025
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2025  
Document Transition Report false  
Entity File Number 001-39083  
Entity Registrant Name Vir Biotechnology, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 81-2730369  
Entity Address, Address Line One 1800 Owens Street  
Entity Address, Address Line Two Suite 900  
Entity Address, City or Town San Francisco  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 94158  
City Area Code 415  
Local Phone Number 906-4324  
Title of 12(b) Security Common stock, par value $0.0001 per share  
Trading Symbol VIR  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   138,238,003
Current Fiscal Year End Date --12-31  
Amendment Flag false  
Entity Central Index Key 0001706431  
Document Fiscal Period Focus Q1  
Document Fiscal Year Focus 2025  
v3.25.1
Condensed Consolidated Balance Sheets - USD ($)
$ in Thousands
Mar. 31, 2025
Dec. 31, 2024
CURRENT ASSETS:    
Cash and cash equivalents $ 273,571 $ 222,947
Short-term investments 517,367 678,051
Restricted cash and cash equivalents, current 88,151 89,385
Equity investments 10,724 4,350
Prepaid expenses and other current assets 42,394 47,725
Total current assets 932,207 1,042,458
Intangible assets, net 8,072 8,120
Goodwill 16,937 16,937
Property and equipment, net 61,681 63,183
Operating lease right-of-use assets 58,559 59,680
Restricted cash and cash equivalents, noncurrent 6,273 6,363
Long-term investments 218,140 190,015
Other assets 5,858 12,057
TOTAL ASSETS 1,307,727 1,398,813
CURRENT LIABILITIES:    
Accounts payable 3,725 5,081
Accrued and other liabilities 104,126 85,873
Deferred revenue, current 11,935 12,648
Contingent consideration obligation, current 17,500 16,060
Total current liabilities 137,286 119,662
Operating lease liabilities, noncurrent 88,170 90,139
Contingent consideration obligation, noncurrent 23,640 24,050
Other long-term liabilities 14,812 14,577
TOTAL LIABILITIES 263,908 248,428
Commitments and contingencies (Note 7)
STOCKHOLDERS’ EQUITY:    
Preferred stock, $0.0001 par value; 10,000,000 shares authorized as of March 31, 2025 and December 31, 2024; no shares issued and outstanding as of March 31, 2025 and December 31, 2024 0 0
Common stock, $0.0001 par value; 300,000,000 shares authorized as of March 31, 2025 and December 31, 2024; 138,063,698 and 136,959,446 shares issued and outstanding as of March 31, 2025 and December 31, 2024, respectively 14 14
Additional paid-in capital 1,926,529 1,911,872
Accumulated other comprehensive loss (1,975) (1,717)
Accumulated deficit (880,749) (759,784)
TOTAL STOCKHOLDERS’ EQUITY 1,043,819 1,150,385
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY $ 1,307,727 $ 1,398,813
v3.25.1
Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares
Mar. 31, 2025
Dec. 31, 2024
Statement of Financial Position [Abstract]    
Preferred stock, par value (in USD per share) $ 0.0001 $ 0.0001
Preferred stock, shares authorized (in shares) 10,000,000 10,000,000
Preferred stock, shares issued (in shares) 0 0
Preferred stock, shares outstanding (in shares) 0 0
Common stock, par value (in USD per share) $ 0.0001 $ 0.0001
Common stock, shares authorized (in shares) 300,000,000 300,000,000
Common stock, shares issued (in shares) 138,063,698 136,959,446
Common stock, shares outstanding (in shares) 138,063,698 136,959,446
v3.25.1
Condensed Consolidated Statements of Operations - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Revenues:    
Total revenues $ 3,032 $ 56,376
Operating expenses:    
Cost of revenue 0 59
Research and development 118,645 100,125
Selling, general and administrative 23,944 36,321
Restructuring, long-lived assets impairment and related charges, net (10) (48)
Total operating expenses 142,579 136,457
Loss from operations (139,547) (80,081)
Other income:    
Change in fair value of equity investments 6,382 (5,915)
Interest income 12,288 21,283
Other expense, net (72) (287)
Total other income 18,598 15,081
Loss before provision for income taxes (120,949) (65,000)
Provision for income taxes (16) (276)
Net loss $ (120,965) $ (65,276)
Net loss per share, basic (in USD per share) $ (0.88) $ (0.48)
Net loss per share, diluted (in USD per share) $ (0.88) $ (0.48)
Weighted-average shares outstanding, basic (in shares) 137,468,900 135,280,648
Weighted-average shares outstanding, diluted (in shares) 137,468,900 135,280,648
Collaboration revenue    
Revenues:    
Total revenues $ (70) $ (987)
Contract revenue    
Revenues:    
Total revenues 1,864 52,191
Grant revenue    
Revenues:    
Total revenues $ 1,238 $ 5,172
v3.25.1
Condensed Consolidated Statements of Comprehensive Loss - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Income Statement [Abstract]    
Net loss $ (120,965) $ (65,276)
Other comprehensive loss:    
Unrealized loss on investments (303) (1,411)
Pension actuarial gain (loss) 45 (171)
Total other comprehensive loss (258) (1,582)
Comprehensive loss $ (121,223) $ (66,858)
v3.25.1
Condensed Consolidated Statements of Stockholders' Equity - USD ($)
$ in Thousands
Total
Common Stock
Additional Paid-in Capital
Accumulated Other Comprehensive Loss
Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2023   134,781,286      
Beginning balance at Dec. 31, 2023 $ 1,590,236 $ 13 $ 1,828,862 $ (815) $ (237,824)
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Vesting of restricted common stock (in shares)   950,254      
Vesting of restricted common stock 1 $ 1      
Exercise of stock options (in shares)   112,020      
Exercise of stock options 220   220    
Stock-based compensation 23,757   23,757    
Other comprehensive loss (1,582)     (1,582)  
Net loss (65,276)       (65,276)
Ending balance (in shares) at Mar. 31, 2024   135,843,560      
Ending balance at Mar. 31, 2024 $ 1,547,356 $ 14 1,852,839 (2,397) (303,100)
Beginning balance (in shares) at Dec. 31, 2024 136,959,446 136,959,446      
Beginning balance at Dec. 31, 2024 $ 1,150,385 $ 14 1,911,872 (1,717) (759,784)
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Vesting of restricted common stock (in shares)   1,011,628      
Vesting of restricted common stock 0        
Exercise of stock options (in shares)   92,624      
Exercise of stock options 598   598    
Stock-based compensation 14,059   14,059    
Other comprehensive loss (258)     (258)  
Net loss $ (120,965)       (120,965)
Ending balance (in shares) at Mar. 31, 2025 138,063,698 138,063,698      
Ending balance at Mar. 31, 2025 $ 1,043,819 $ 14 $ 1,926,529 $ (1,975) $ (880,749)
v3.25.1
Condensed Consolidated Statements of Cash Flows - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
CASH FLOWS FROM OPERATING ACTIVITIES:    
Net loss $ (120,965) $ (65,276)
Adjustments to reconcile net loss to net cash used in operating activities:    
Change in estimated constraint on profit-sharing amount 0 685
Depreciation and amortization 2,867 4,517
Amortization of premiums on investments, net 4,089 238
Noncash lease expense 1,121 1,447
Change in fair value of equity investments (6,382) 5,915
Change in estimated fair value of contingent consideration 1,030 1,650
Stock-based compensation 14,059 23,757
Other non-cash items, net 6 (176)
Changes in operating assets and liabilities:    
Prepaid expenses and other current assets 5,058 1,433
Other assets 6,200 (86)
Accounts payable (1,415) 735
Accrued liabilities and other long-term liabilities 18,725 (30,003)
Operating lease liabilities (1,796) (4,067)
Deferred revenue (713) (50,159)
Net cash used in operating activities (78,116) (109,390)
CASH FLOWS FROM INVESTING ACTIVITIES:    
Proceeds from sale of equipment 281 533
Purchases of property and equipment (1,629) (1,872)
Purchases of investments (173,694) (562,939)
Maturities and sales of investments 301,860 592,698
Net cash provided by investing activities 126,818 28,420
CASH FLOWS FROM FINANCING ACTIVITIES:    
Payment of principal on financing lease obligation 0 (69)
Proceeds from exercise of stock options 598 221
Net cash provided by financing activities 598 152
Net increase (decrease) in cash, cash equivalents and restricted cash and cash equivalents 49,300 (80,818)
Cash, cash equivalents and restricted cash and cash equivalents at beginning of period 318,695 261,292
Cash, cash equivalents and restricted cash and cash equivalents at end of period 367,995 180,474
RECONCILIATION OF CASH, CASH EQUIVALENTS AND RESTRICTED CASH AND CASH EQUIVALENTS TO THE CONDENSED CONSOLIDATED BALANCE SHEETS:    
Cash and cash equivalents 273,571 160,711
Restricted cash and cash equivalents, current 88,151 13,335
Restricted cash and cash equivalents, noncurrent 6,273 6,428
Total cash, cash equivalents and restricted cash and cash equivalents $ 367,995 $ 180,474
v3.25.1
Organization
 3 Months Ended
Mar. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Organization Organization
Business Overview
Vir Biotechnology, Inc. (Vir Bio or the Company) is a clinical-stage biopharmaceutical company focused on powering the immune system to transform lives by discovering and developing medicines for serious infectious diseases and cancer. Its clinical-stage portfolio includes infectious disease programs for chronic hepatitis delta and chronic hepatitis B infections and multiple dual-masked T-cell engagers (TCEs) across validated targets in solid tumor indications. Vir Bio also has a preclinical portfolio of programs across a range of infectious diseases and oncologic malignancies. Vir Bio has exclusive rights to the PRO-XTEN™ masking platform for oncology and infectious disease. PRO-XTEN™ is a trademark of Amunix Pharmaceuticals, Inc., a Sanofi company.
Liquidity and Capital Resources
In November 2023, the Company entered into a sales agreement (Sales Agreement) with Cowen and Company, LLC, as sales agent (TD Cowen), pursuant to which the Company may from time to time offer and sell shares of its common stock for an aggregate offering price of up to $300.0 million, through or to TD Cowen, acting as sales agent or principal. The shares will be offered and sold under the Company’s shelf registration statement on Form S-3 and a related prospectus filed with the U.S. Securities and Exchange Commission (SEC) on November 3, 2023. The Company will pay TD Cowen a commission of up to 3.0% of the aggregate gross proceeds from each sale of shares, reimburse legal fees and disbursements and provide TD Cowen with customary indemnification and contribution rights. As of March 31, 2025, no shares have been sold under the Sales Agreement.
As of March 31, 2025, the Company had $1.02 billion in cash, cash equivalents, and investments, which the Company believes will be sufficient to fund its operations for a period through at least twelve months from the issuance date of these unaudited condensed consolidated financial statements. The Company also had $94.4 million in restricted cash and cash equivalents as of March 31, 2025.
v3.25.1
Summary of Significant Accounting Policies
 3 Months Ended
Mar. 31, 2025
Accounting Policies [Abstract]  
Summary of Significant Accounting Policies Summary of Significant Accounting Policies
Basis of Presentation and Principles of Consolidation
The Company’s unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP) and applicable rules and regulations of the SEC regarding interim financial reporting. All intercompany balances and transactions have been eliminated upon consolidation. The unaudited interim condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements and reflect, in the opinion of management, all adjustments of a normal and recurring nature that are necessary for the fair presentation of the Company’s financial information. The unaudited condensed consolidated results of operations for the three months ended March 31, 2025 are not necessarily indicative of the results to be expected for the year ending December 31, 2025, or for any other future annual or interim period.
Certain information and footnote disclosures typically included in the Company’s annual consolidated financial statements have been condensed or omitted. As such, these unaudited interim condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and related notes included in the Annual Report on Form 10-K for the year ended December 31, 2024.
Use of Estimates
The preparation of the unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could materially differ from those estimates.
Segments
Operating segments are defined as components of an entity about which separate discrete information is available for evaluation by the chief operating decision maker (CODM) in deciding how to allocate resources and in assessing performance. The Company manages the business activities on a consolidated basis and operates as one reportable segment that constitutes all of the consolidated entity, which is the business of powering the immune system to transform lives by discovering and developing medicines for serious infectious diseases and cancer. Factors used in determining the reportable segment include the nature of the Company’s operating activities, the organizational and reporting structure, and the type of information regularly provided to the CODM to allocate resources and evaluate financial performance. The Company’s CODM is its Chief Executive Officer.
Cash Equivalents
The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents, which consist of amounts invested primarily in money market funds and are stated at fair value.
Investments
Investments include available-for-sale debt securities and equity investments, which are carried at fair value.
Available-for-Sale Debt Securities
The Company’s valuations of marketable securities are generally derived from independent pricing services based on quoted prices in active markets for similar securities at period end. Generally, investments with original maturities beyond three months at the date of purchase and that mature at, or less than 12 months from, the unaudited condensed consolidated balance sheet date are considered short-term investments, with all others considered to be long-term investments. Unrealized gains and losses deemed temporary in nature are reported as a component of accumulated other comprehensive loss. The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity, which is included in interest income on the unaudited condensed consolidated statements of operations. The cost of securities sold is based on the specific identification method.
Equity Investments
The Company measures its investment in equity securities at fair value at each reporting date based on the market price at period end if it has a readily determinable fair value. Otherwise, the investments in equity securities are measured at cost less impairment, adjusted for observable price changes for identical or similar investments of the same issuer unless the Company has significant influence or control over the investee. Changes in fair value resulting from observable price changes are presented as change in fair value of equity investments, and changes in fair value resulting from foreign currency translation are included in other expense, net on the unaudited condensed consolidated statements of operations.
Restricted Cash and Cash Equivalents
Restricted cash and cash equivalents primarily includes the $75.0 million milestone payment due upon VIR-5525 achieving “first in human dosing” by 2026, amounts that may need to be refunded to the Gates Foundation and money market funds to secure standby letters of credit and security deposits with financial institutions under lease agreements.
Research and Development Expenses
To date, research and development expenses have related primarily to discovery efforts and preclinical and clinical development of product candidates. Research and development expenses are recognized as incurred, and payments made prior to the receipt of goods or services to be used in research and development are capitalized until the goods or services are received. Research and development expenses include expenses related to license and collaboration agreements; contingent consideration from business acquisitions; personnel-related expenses, including salaries, benefits, and stock-based compensation for personnel contributing to research and development activities; expenses incurred under agreements with third-party contract manufacturing organizations, contract research organizations, and consultants; clinical costs, including laboratory supplies and costs related to compliance with regulatory requirements; and other allocated expenses, including expenses for rent, facilities maintenance, and depreciation and amortization.
The Company has acquired and may continue to acquire the rights to develop and commercialize new product candidates from third parties. Upfront payments and research and development milestone payments made in connection with acquired licenses or product rights are expensed as incurred, provided that they do not relate to a regulatory approval milestone or assets acquired in a business combination.
The Company’s expense accruals for clinical trials and manufacturing are based on estimates of contracted services provided by third-party vendors not yet billed. When billing terms under these contracts do not coincide with the timing of when the work is performed, the Company is required to make estimates of its outstanding obligations to those third parties as of the period end. The accrual estimates are based on a number of factors, including the Company’s knowledge of the research and development programs and clinical manufacturing activities, the status of the programs and activities, invoicing to date, and the provisions in the contracts. The Company obtains information regarding unbilled services directly from these service providers and performs procedures to support its estimates based on its internal understanding of the services provided to date. However, the Company may also be required to estimate these services based on information available to its internal clinical and manufacturing administrative staff if such information is not able to be obtained timely from its service providers
New Accounting Pronouncement Not Yet Adopted
In December 2023, the Financial Accounting Standards Board (FASB) issued Accounting Standards Updates (ASU) No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which modifies the rules on income tax disclosures to require entities to disclose (1) specific categories in the rate reconciliation, (2) the income or loss from continuing operations before income tax expense or benefit (separated between domestic and foreign) and (3) income tax expense or benefit from continuing operations (separated by federal, state and foreign). ASU 2023-09 also requires entities to disclose their income tax payments to international, federal, state and local jurisdictions, among other changes. The guidance is effective for annual periods beginning after December 15, 2024. Early adoption is permitted. ASU 2023-09 should be applied on a prospective basis, but retrospective application is permitted. The Company is currently evaluating the impact the adoption of ASU 2023-09 may have on its annual consolidated financial statements and related disclosures.
In November 2024, the FASB issued ASU No. 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (ASU 2024-03), which requires entities to disclose specific information on the types of expenses included in the expense captions presented on the face of the income statement as well as disclosures about selling expenses. The guidance is effective for annual periods beginning after December 15, 2026 and interim periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. ASU 2024-03 should be applied on a prospective basis, but retrospective application is permitted. The Company is currently evaluating the impact the adoption of ASU 2024-03 may have on its consolidated financial statements and related disclosures.
Reclassification
Certain reclassifications have been made to prior period amounts on the Company’s condensed consolidated statements of operations to conform to the current period presentation and enhance comparability. As a result, certain amounts related to restructuring activities and long-lived assets impairment and disposal gains or losses, previously reflected in selling, general and administrative, were reclassified to restructuring, long-lived assets impairment and related charges, net. These reclassifications had no impact on previously reported total revenues, total operating expenses, or net loss.
Certain reclassifications have been made to prior period amounts on the Company’s condensed consolidated statements of cash flows to conform to the current period presentation and enhance comparability. As a result, certain amounts related to collaboration receivables, previously reflected in changes in operating assets and liabilities – receivable from collaboration, were reclassified to changes in operating assets and liabilities – prepaid assets and other current assets.
v3.25.1
Fair Value Measurements
 3 Months Ended
Mar. 31, 2025
Fair Value Disclosures [Abstract]  
Fair Value Measurements Fair Value Measurements
The Company determines the fair value of financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows:
•Level 1: Inputs that include quoted prices in active markets for identical assets and liabilities.
•Level 2: Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
•Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.
The carrying amounts of certain financial instruments, including accounts payable and accrued liabilities, approximate fair value due to their relatively short maturities.
Cash Equivalents and Available-for-Sale Securities
The following tables summarize the Company’s Level 1 and Level 2 financial assets measured at fair value on a recurring basis by level within the fair value hierarchy as of March 31, 2025 and December 31, 2024 (in thousands):
March 31, 2025
Valuation
Hierarchy		Amortized
Cost		Gross
Unrealized
Holding
Gains		Gross
Unrealized
Holding
Losses 		Aggregate
Fair Value
Assets:
Money market fundsLevel 1$168,828 $— $— $168,828 
U.S. government treasuriesLevel 2450,270 406 (10)450,666 
U.S. government agency bonds and discount notesLevel 267,991 36 (29)67,998 
Asset-backed securities Level 258,515 177 (1)58,691 
Corporate bondsLevel 2243,488 538 (3)244,023 
Equity securitiesLevel 1N/AN/AN/A10,724 
Total financial assets$989,092 $1,157 $(43)$1,000,930 
Reconciliation to cash, cash equivalents and investments on condensed consolidated balance sheet
Minus: Restricted cash equivalents invested in money market funds(18,957)
Plus: Cash deposits37,829 
Total cash, cash equivalents and investments$1,019,802 
December 31, 2024
Valuation
Hierarchy		Amortized
Cost		Gross
Unrealized
Holding
Gains		Gross
Unrealized
Holding
Losses 		Aggregate
Fair Value
Assets:
Money market fundsLevel 1$146,505 $— $— $146,505 
U.S. government treasuriesLevel 2588,794 722 (33)589,483 
U.S. government agency bonds and discount notesLevel 238,081 17 (19)38,079 
Asset-back securitiesLevel 251,038 220 (10)51,248 
Corporate bondsLevel 2252,935 529 (9)253,455 
Equity securitiesLevel 1N/AN/AN/A 4,350 
Total financial assets$1,077,353 $1,488 $(71)$1,083,120 
Reconciliation to cash, cash equivalents and investments on condensed consolidated balance sheet
Minus: Restricted cash equivalents invested in money market funds(20,281)
Plus: Cash deposits32,524 
Total cash, cash equivalents and investments$1,095,363 
Accrued interest receivables excluded from both the fair value and amortized cost basis of the available-for-sale debt securities are presented within prepaid expenses and other current assets in the unaudited condensed consolidated balance sheets. Accrued interest receivables amounted to $5.4 million and $5.0 million as of March 31, 2025 and December 31, 2024, respectively. The Company did not write off any accrued interest receivables during the three months ended March 31, 2025 and 2024.
The Company recognized total net unrealized gains of $1.1 million and $1.4 million in accumulated other comprehensive loss as of March 31, 2025 and December 31, 2024, respectively. The gross unrealized losses as of March 31, 2025 were due to changes in interest rates and temporary in nature. The Company currently does not intend, and it is highly unlikely that it will be required, to sell these securities before recovery of their amortized cost basis. As of March 31, 2025, no securities have contractual maturities (or weighted average life for asset-backed securities) of longer than two years.
As of March 31, 2025, the Company’s equity investment consisted solely of ordinary shares of Brii Biosciences Limited (Brii Bio Parent). The equity securities of Brii Bio Parent are listed on the Stock Exchange of Hong Kong Limited and are considered to be marketable equity securities measured at fair value at each reporting date. As of March 31, 2025, the Company remeasured the equity investment at a fair value of $10.7 million. The Company recognized an unrealized gain of $6.4 million and an unrealized loss of $5.9 million for the three months ended March 31, 2025 and 2024, respectively, as part of other income in the unaudited condensed consolidated statement of operations. For the three months ended March 31, 2025 and 2024, the unrealized gains or losses related to foreign currency translation were not material.
Contingent Consideration
Contingent consideration primarily includes potential milestone payments in connection with the acquisitions of Humabs BioMed SA (Humabs) in 2017. The Company classifies the contingent consideration as Level 3 financial liabilities within the fair value hierarchy as of March 31, 2025 and December 31, 2024. The estimated fair value of the contingent consideration related to the Humabs acquisition was determined by calculating the probability-weighted clinical, regulatory and commercial milestone payments based on the assessment of the likelihood and estimated timing that certain milestones would be achieved.
During the three months ended March 31, 2025, the Company achieved $17.5 million clinical milestone upon the enrollment of the first patient in phase 3 ECLIPSE registrational program for chronic hepatitis delta. As of March 31, 2025, the Company recorded this $17.5 million as contingent consideration obligation, current on its unaudited condensed balance sheets and calculated the estimated fair value of the remaining clinical and regulatory milestones related to tobevibart using the following significant unobservable inputs:
Unobservable inputValue
Discount rates12.1%
Probability of achievement67.5%
For the commercial milestones, the Company used a Monte Carlo simulation because of the availability of discrete revenue forecasts. As of March 31, 2025, the Monte Carlo simulation assumed a commercial product launch and associated discrete revenue forecasts, as well as the following significant unobservable inputs for the remaining commercial milestones related to tobevibart:
Unobservable inputValue
Volatility55.0%
Discount rate10.0%
Probability of achievement67.5%
The discount rate captures the credit risk associated with the payment of the contingent consideration when earned and due. As of March 31, 2025 and December 31, 2024, the estimated fair value of the contingent consideration related to the Humabs acquisition was $41.1 million and $40.1 million, respectively, with changes in the estimated fair value recorded in research and development expenses in the unaudited condensed consolidated statements of operations. The estimated fair value of the contingent consideration related to the Humabs acquisition involves significant estimates and assumptions, which give rise to measurement uncertainty.
The following table sets forth the changes in the estimated fair value of the Company’s contingent consideration obligations (in thousands):
Contingent
Consideration Obligation
Balance at December 31, 2024$40,110 
Changes in fair value1,030 
Balance at March 31, 2025$41,140 
v3.25.1
Grant Agreements
 3 Months Ended
Mar. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Grant Agreements Grant Agreements
Gates Foundation Grants
The Company has entered into various grant agreements with the Gates Foundation (formerly known as the Bill & Melinda Gates Foundation), under which it is currently awarded grants totaling up to $49.9 million to support its HIV vaccine program, tuberculosis vaccine program, HIV vaccinal antibody program and malaria vaccinal antibody program. The term of the grant agreements will expire at various dates through June 2027, unless terminated earlier by the Gates Foundation for the Company’s breach, failure to progress the funded project, in the event of the Company’s change of control, change in the Company’s tax status, or significant changes in the Company’s leadership that the Gates Foundation reasonably believes may threaten the success of the projects.
Concurrently with the execution of the grant agreement for the vaccinal antibody program, the Company entered into a stock purchase agreement with the Gates Foundation, under which the Gates Foundation purchased 881,365 shares of the Company’s common stock on January 13, 2022, at a price per share of $45.38, for an aggregate purchase price of approximately $40.0 million. The fair market value of the common stock issued to the Gates Foundation was $28.5 million, based on the closing stock price of $37.65 per share on the closing date and taking into account a discount for the lack of marketability due to the restrictions in place on the underlying shares, resulting in a $11.3 million premium received by the Company. The Company accounted for the common stock issued to the Gates Foundation based on its fair market value on the closing date and determined that the premium paid by the Gates Foundation should be included in the deferred revenue from the vaccinal antibody grant.
In August 2024, the Company announced a strategic realignment that included phasing out certain research programs, which included the HIV vaccine program and the tuberculosis vaccine program funded by Gates Foundation grants. The Company continues to pursue a cure for HIV in collaboration with the Gates Foundation.
Payments received in advance that are related to future research activities along with the aforementioned premium received are deferred and recognized as revenue when the donor-imposed conditions are met, which is as the research and development activities are performed. The premium received by the Company is deferred and recognized over the same period as the grant proportionally. The Company recognized grant revenue of $1.2 million and $1.9 million for the three months ended March 31, 2025 and 2024, respectively. As of March 31, 2025 and December 31, 2024, the Company had deferred revenue of $10.4 million and $11.1 million, respectively. As of March 31, 2025 and December 31, 2024, the Company had $11.2 million and $11.6 million, respectively, within accrued and other liabilities, which may need to be refunded to the Gates Foundation.
v3.25.1
Collaboration and License Agreements
 3 Months Ended
Mar. 31, 2025
Revenue Recognition [Abstract]  
Collaboration and License Agreements Collaboration and License Agreements
License Agreement with Sanofi
On September 9, 2024 (Acquisition Date), the Company closed the license agreement with Amunix Pharmaceuticals, Inc., a Sanofi company, previously announced on August 1, 2024 (Sanofi Agreement). The Sanofi Agreement provides the Company with an exclusive worldwide license to use of the proprietary PRO-XTEN™ universal masking technology for oncology and infectious disease,excluding the ophthalmological field, and to three early clinical-stage dual-masked TCEs that all leverage the PRO-XTEN™ universal masking platform within a range of oncology indications.
Under the Sanofi Agreement the Company made an upfront payment to Sanofi in the amount of $100.0 million and placed into escrow a $75.0 million milestone payment due to former shareholders of Amunix Pharmaceuticals, Inc., which is subject to VIR-5525 achieving “first in human dosing” by 2026. The cash paid into escrow is under the control of the Company and is classified as restricted cash and cash equivalents, current in the unaudited condensed consolidated balance sheets. Sanofi will also be eligible to receive up to an additional $323.0 million in future development and regulatory milestone payments, up to an additional $1.49 billion in commercial net sales-based milestone payments, and low single-digit to low double-digit tiered royalties on worldwide net sales. In addition, if, within a two-year period from the execution of the Sanofi Agreement, the Company executes a transaction that gives rise to Vir Bio receiving certain sublicense income related to the licenses obtained from the Sanofi Agreement, Sanofi may be eligible to receive a portion of such income.
Additionally, as part of the Sanofi Agreement, the Company paid $3.7 million to acquire certain lab equipment and cash deposits primarily related to contract manufacturing agreements. Shortly after the closing of the Sanofi Agreement, the Company hired certain former Sanofi personnel. The Company incurred approximately $4.6 million of transaction costs associated with the closing of the Sanofi Agreement. The following table summarizes the aggregate amount paid for the assets acquired by the Company in connection with the Sanofi Agreement as of the Acquisition Date (in thousands):
Upfront $100,000 
Equipment 1,150 
Deposits 2,580 
Transaction costs 4,612 
Total purchase consideration$108,342 
The Company accounted for the Sanofi Agreement as an asset acquisition in accordance ASC 805-50 as substantially all of the fair value of the assets acquired is concentrated in a group of similar identifiable assets. The three early clinical stage oncology TCEs use the same universal PRO-XTEN™ masking technology and have similar development timelines, probabilities of risk, and loss of patent exclusivity among other characteristics. ASC 805-50 requires the acquiring entity in an asset acquisition to recognize assets acquired and liabilities assumed based on the cost to the acquiring entity on a relative fair value basis, which includes consideration given. The total purchase price was allocated to the acquired assets based on their relative fair values, as of the Acquisition Date as follows (in thousands):
In-process research and development$102,836 
Property and equipment 1,119 
Prepaid expenses and other current assets (1)
3,975 
Assembled workforce412 
Total purchase consideration$108,342 
__________________________________________________________
(1) Includes acquired cash deposits primarily related to contract manufacturing agreements.
The fair value of the IPR&D was estimated using a multi-period excess earnings income approach that discounts expected cash flows to present value by applying a discount rate that represents the estimated rate that market participants would require for the intangible asset. The expected cash flows and related discount rate are significant unobservable inputs categorized within Level 3 of the fair value hierarchy. In accordance with ASC 730, as the three early clinical stage oncology TCEs have not achieved regulatory approval when acquired, the portion of the purchase price allocated to the IPR&D was immediately expensed to research and development expenses as they had no alternative future use. Contingent milestone payments were determined to be within the scope of ASC 450 and will be recognized when the contingency is resolved and the consideration is paid or becomes payable. Any milestone payments made in the future will either be expensed as research and development or capitalized as a developed asset based on when regulatory approval is obtained. The Company will recognize sales-based milestone and royalty payments in cost of sales as revenue from product sales is recognized. The fair value of the assembled workforce was estimated using a replacement cost method. The assembled workforce is classified as intangible assets, net and is amortized over an expected useful life of five years.
Alnylam Pharmaceuticals, Inc.
In October 2017, the Company and Alnylam Pharmaceuticals, Inc. (Alnylam) entered into a collaboration and license agreement (the Alnylam Agreement). Under the Alnylam Agreement, the Company obtained a worldwide, exclusive license to develop, manufacture and commercialize siRNA product candidates, including elebsiran, for all uses and purposes including the treatment of hepatitis B virus (HBV) and hepatitis delta virus (HDV). Under the Alnylam Agreement, the Company also held options to obtain similar licenses to siRNA product candidates for up to four other infectious disease targets selected by Vir Bio, but following an amendment and restatement of the Alnylam Agreement in March 2025 (the Restated Alnylam Agreement), those options (and all rights and obligations related to those infectious disease targets) were terminated. At the same time Alnylam elected to not opt-in to the profit-sharing arrangement with respect to any approved siRNA product candidates, including elebsiran, directed to HBV or HDV. The Company remains solely responsible, at its expense, for conducting all development, manufacture and commercialization activities for elebsiran in HBV and HDV indications, and the Company is required to use commercially reasonable efforts to develop and commercialize elebsiran for the treatment of HBV or HDV in the United States and specified major markets.
In connection with the Restated Alnylam Agreement and Alnylam’s election to not opt-in to the profit-sharing arrangement, the Company agreed to pay Alnylam $30.0 million, which was recorded as part of research and development expenses in the Company’s unaudited condensed statement of operations for the three months ended March 31, 2025 and as part of accrued and other liabilities on its unaudited condensed balance sheets as of March 31, 2025. After this payment, the remaining amount of the development and regulatory milestones is up to $145.0 million, down from the $175.0 million as previously disclosed in the audited consolidated financial statements included in the Annual Report on Form 10-K for the year ended December 31, 2024. Any development and regulatory milestones for an elebsiran product will be payable to Alnylam only once, irrespective of dosage, formulation forms, route of administration or indication. Following commercialization, the Company will be required to pay to Alnylam up to $250.0 million in the aggregate for the first achievement of specified levels of net sales by elebsiran products directed to HBV, whether for the treatment of HBV or HDV. The Company will also be required to pay Alnylam tiered royalties at percentages ranging from the low double-digits to mid-teens on annual net sales of siRNA products directed to HBV, such as elebsiran, whether for the treatment of HBV or HDV, subject to specified reductions and offsets. The royalties are payable on a product-by-product and country-by-country basis until the later of the expiration of all valid claims of specified patents covering such product in such country and 10 years after the first commercial sale of such product in such country. Alnylam is also entitled to receive a portion of any consideration the Company receives as a result of granting a sublicense under the licenses granted to Vir Bio by Alnylam under the Alnylam Agreement.
The term of the Restated Alnylam Agreement will continue, on a product-by-product and country-by-country basis, until expiration of all royalty payment obligations under the Restated Alnylam Agreement. The Company may terminate the Alnylam Agreement on a program-by-program basis or in its entirety for any reason on 90 days’ written notice. Either party may terminate the agreement for cause for the other party’s uncured material breach on 60 days’ written notice (or 30 days’ notice for payment breach), or if the other party challenges the validity or enforceability of any patent licensed to it under the Restated Alnylam Agreement on 30 days’ notice.
The Company did not incur material expenses during the three months ended March 31, 2024 related to collaboration with Alnylam.
v3.25.1
Balance Sheet Components
 3 Months Ended
Mar. 31, 2025
Balance Sheet Related Disclosures [Abstract]  
Balance Sheet Components Balance Sheet Components
Property and Equipment, net
Property and equipment, net consists of the following (in thousands). Depreciation expenses were $2.8 million and $4.4 million for the three months ended March 31, 2025 and 2024, respectively.
Useful life
(in years)		March 31,
2025		December 31,
2024
Leasehold improvements
8 - 12
$53,981 $53,992 
Laboratory equipment539,426 39,428 
Furniture and fixtures52,715 2,696 
Computer equipment32,621 2,778 
Construction in progressN/A1,808 1,074 
Property and equipment, gross100,551 99,968 
Less: accumulated depreciation(38,870)(36,785)
Total property and equipment, net$61,681 $63,183 
Accrued and Other Liabilities
Accrued and other liabilities consist of the following (in thousands):
March 31,
2025		December 31,
2024
Research and development expenses$67,893 $29,225 
Payroll and related expenses11,611 31,165 
Excess funds payable under grant agreements11,177 11,589 
Operating lease liabilities, current7,925 7,752 
Other professional and consulting expenses2,068 2,268 
Other accrued expenses3,452 3,874 
Total accrued and other liabilities$104,126 $85,873 
v3.25.1
Commitments and Contingencies
 3 Months Ended
Mar. 31, 2025
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies
Manufacturing and Supply Agreements
In the first quarter of 2024, the Company and a third-party contract development manufacturing organization entered into various scopes of work with respect to the manufacturing of tobevibart (Tobevibart Agreements). As of March 31, 2025, the Company had unaccrued unpaid commitments of approximately $22 million under the Tobevibart Agreements. In the third quarter of 2024, the Company and a third-party contract development manufacturing organization entered into various scopes of work with respect to the manufacturing of elebsiran (Elebsiran Agreements). As of March 31, 2025, the Company had unaccrued unpaid commitments of approximately $8 million under the Elebsiran Agreements.
Legal Proceedings
The Company may from time to time be party to claims and legal proceedings that arise in the normal course of its business and that may or may not have, individually or in the aggregate, a material adverse effect on its results of operations, financial condition or liquidity.
Indemnification
In the ordinary course of business, the Company enters into agreements that may include indemnification provisions. Under such agreements, the Company may indemnify, hold harmless and defend an indemnified party for losses suffered or incurred by the indemnified party. In some cases, the indemnification will continue after the termination of the agreement. The maximum potential amount of future payments the Company could be required to make under these provisions is not determinable. In addition, the Company has entered into indemnification agreements with its directors and certain officers that may require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. To date, no demands have been made upon the Company to provide indemnification under these agreements, and thus, there are no indemnification claims that the Company is aware of that could have a material effect on the unaudited condensed consolidated balance sheets, unaudited condensed consolidated statements of operations, or unaudited condensed consolidated statements of cash flows.
v3.25.1
Stock-Based Awards
 3 Months Ended
Mar. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Stock-Based Awards Stock-Based Awards
The Company has maintained a stock incentive plan for the issuance of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock, other stock awards and performance cash awards, to employees, non-employee directors, and consultants. The Company also has an employee stock purchase plan (ESPP) for its employees.
Stock Options Granted to Employees
The fair value of stock options granted to employees was estimated on the date of grant using the Black-Scholes option-pricing model with the following assumptions:
Three Months Ended March 31,
20252024
Expected term of options (in years)6.16.1
Expected stock price volatility
89.5% – 89.9%
89.2% – 89.3%
Risk-free interest rate
4.1% – 4.5%
4.3%
Expected dividend yield——
The valuation assumptions for stock options were determined as follows:
Expected Term — The expected term represents the period that the stock options granted are expected to be outstanding and is determined using the simplified method (based on the mid-point between the vesting date and the end of the contractual term) as the Company has limited historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for its stock option grants.
Expected Volatility — The expected volatility is determined by using a blended approach of the Company and its industry peers’ historical volatilities.
Risk-Free Interest Rate — The Company determines the risk-free interest rate over the expected term of the stock options based on the constant maturity rate of U.S. Treasury securities with similar maturities as of the date of the grant.
Expected Dividend Rate — The expected dividend is zero as the Company has not paid nor does it anticipate paying any dividends on its profit interest units in the foreseeable future.
Stock-Based Compensation Expense
Stock-based compensation is recognized on a straight-line basis over the requisite service period, which is generally the vesting period. The following table sets forth the total stock-based compensation expense for all awards granted to employees and non-employees and the ESPP in the unaudited condensed consolidated statements of operations (in thousands):
Three Months Ended March 31,
20252024
Research and development$7,005 $13,606 
Selling, general and administrative7,054 10,151 
Total stock-based compensation$14,059 $23,757 
v3.25.1
Net Loss Per Share
 3 Months Ended
Mar. 31, 2025
Earnings Per Share [Abstract]  
Net Loss Per Share Net Loss Per Share
Basic net loss per common share is computed by dividing the net loss by the weighted-average number of common shares outstanding during the period, without consideration of common stock equivalents. Diluted net loss per common share is computed by dividing the net loss by the sum of the weighted-average number of common shares outstanding during the period plus any potential dilutive effects of common stock equivalents outstanding during the period calculated in accordance with the treasury stock method. For periods that the Company was in a net loss position, basic net loss per share is the same as diluted net loss per share as the inclusion of all potential common securities outstanding would have been anti-dilutive.
The following is a calculation of the basic and diluted net loss per share (in thousands, except share and per share data):
Three Months Ended March 31,
20252024
Net loss$(120,965)$(65,276)
Weighted-average shares outstanding, basic and diluted137,468,900135,280,648
Net loss per share, basic and diluted$(0.88)$(0.48)
Securities that could potentially dilute basic net loss per common share in the future that were not included in the computation of diluted net loss per common share because to do so would have been antidilutive for the periods presented were as follows:
Three Months Ended March 31,
20252024
Options issued and outstanding11,080,15912,018,822
Restricted shares subject to future vesting6,888,4624,521,874
Total17,968,62116,540,696
v3.25.1
Income Taxes
 3 Months Ended
Mar. 31, 2025
Income Tax Disclosure [Abstract]  
Income Taxes Income Taxes
The table below presents our loss before provision for income taxes, provision for income taxes and effective tax rate for the three months ended March 31, 2025 and 2024(in thousands):
Three Months Ended March 31,
20252024
Loss before provision for income taxes$(120,949)$(65,000)
Provision for income taxes$(16)$(276)
Effective tax rate— %(0.4 %)
The Company is subject to income taxes in the United States and foreign jurisdictions. These foreign jurisdictions have statutory tax rates different from those in the United States. Accordingly, the Company’s effective tax rates will vary depending on the relative proportion of foreign to United States income/loss, the utilization of net operating loss and tax credit carry forwards and carrybacks, changes in jurisdictional mix of income and expense, changes in management’s assessment of matters such as the ability to realize deferred tax assets, and changes in tax laws.
Unrecognized tax benefits were $18.5 million and $17.9 million as of March 31, 2025 and December 31, 2024, respectively, and if recognized, would favorably affect the effective tax rate in future periods.
v3.25.1
Segment Reporting
 3 Months Ended
Mar. 31, 2025
Segment Reporting [Abstract]  
Segment Reporting Segment Reporting
The Company manages the business activities on a consolidated basis and operates as one reportable segment that constitutes all of the consolidated entity, which is the business of powering the immune system to transform lives by discovering and developing medicines for serious infectious diseases and cancer. The Company’s CODM is its Chief Executive Officer. The accounting policies of the segment are the same as those described in the summary of significant accounting policies. The measure of segment profit or loss is segment net loss that also is reported on the consolidated statements of operations as consolidated net loss. The measure of segment assets is reported on the balance sheet as total consolidated assets. The CODM uses segment net loss to monitor spending, assess performance for the Company and management, evaluate the progress of completing corporate goals, decide how to allocate resources among the Company’s clinical and pre-clinical portfolios, and make strategic decisions about business development opportunities.
The segment revenue, segment profit or loss, and significant segment expenses regularly provided to CODM are summarized as follows (in thousands).
Three Months Ended
March 31,
20252024
Segment revenue$3,032 $56,376 
Less: Segment expenses (1)
Cost of revenue— 59 
Research and development
Contract manufacturing9,336 9,669 
Clinical costs20,606 11,607 
Personnel (2)
33,718 46,190 
Licenses, collaborations and contingent consideration36,591 5,696 
Other R&D (3)
18,394 26,963 
Selling, general and administrative (2)
23,944 36,321 
Restructuring, long-lived assets impairment and related charges, net(10)(48)
Plus: Other segment items (4)
18,582 14,805 
Segment and consolidated net loss$(120,965)$(65,276)
(1) Refer to Note 6 Balance Sheet Components for depreciation and amortization expenses included in segment expenses.
(2) Refer to Note 8 Stock-Based Awards for stock-based compensation expenses included in segment expenses.
(3) Other research and development expenses primarily includes non-personnel research expenses, allocated facility and IT expenses, IPR&D impairment, and depreciation expenses.
(4) Other segment items include change in fair value of equity investments, interest income, other expense, net, and provision for income taxes, all of which were presented on the condensed consolidated statements of operations.
The following table summarizes segment revenues by geographic area (in thousands). The revenues attributed to foreign customers primarily include collaboration and contract revenues recognized under the Company’s collaboration agreements with GSK, contract revenue generated from clinical supplies provided to foreign companies, and license revenue from the Company’s collaboration with Brii Bio.
Three Months Ended
March 31,
Segment revenues attributed to:20252024
U.S. customers$1,238 $5,172 
Foreign customers
GSK(70)50,694 
Other1,864 510 
Total segment and consolidated revenue$3,032 $56,376 
The Company’s long-lived assets are primarily located in the U.S.
v3.25.1
Pay vs Performance Disclosure - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Pay vs Performance Disclosure    
Net loss $ (120,965) $ (65,276)
v3.25.1
Insider Trading Arrangements
 3 Months Ended
Mar. 31, 2025
shares
Trading Arrangements, by Individual  
Non-Rule 10b5-1 Arrangement Adopted false
Rule 10b5-1 Arrangement Terminated false
Non-Rule 10b5-1 Arrangement Terminated false
Vicki Sato [Member]  
Trading Arrangements, by Individual  
Material Terms of Trading Arrangement
On March 27, 2025, for estate and financial planning reasons, Vicki Sato, Ph.D., the Chair of our Board of Directors, adopted a Rule 10b5-1 trading plan for the sale of our common stock that is intended to satisfy the affirmative defense conditions of Exchange Act Rule 10b5-1(c) (the Sato Trading Plan). The Sato Trading Plan provides for potential sale activity from July 1, 2025 through June 30, 2026, with monthly market orders covering up to an aggregate of 264,000 shares of our common stock (the Sato Shares). The Sato Shares represent approximately 20% of the Company shares she holds currently. Dr. Sato has held the Sato Shares for over 7 years from the date she acquired them on January 7, 2017. The Sato Trading Plan also provides for potential sale activity from July 1, 2025 through June 30, 2026, with limit orders covering up to an aggregate of 82,377 shares of our common stock subject to vested stock options (the Sato Options). The Sato Options to potentially be exercised and sold represent approximately 41% of the in-the-money vested stock options held by Dr. Sato. The Sato Trading plan will expire upon the earlier of (i) the date all sales contemplated by the Sato Trading Plan have been executed, or (ii) June 30, 2026. Each limit order contemplated by the Sato Trading Plan will remain open until the expiration of the plan on June 30, 2026, if not executed sooner. Under the Company’s 10b5-1 plan guidelines, Dr. Sato is prohibited from selling more than 50,000 shares in a single trading day. Dr. Sato will remain in compliance with the Company’s equity ownership guidelines if the Sato Shares and Sato Options are sold under the Sato Trading Plan.
Name Vicki Sato
Title Chair of our Board of Directors
Rule 10b5-1 Arrangement Adopted true
Adoption Date March 27, 2025
Expiration Date June 30, 2026
Arrangement Duration 364 days
Aggregate Available 264,000
v3.25.1
Summary of Significant Accounting Policies (Policies)
 3 Months Ended
Mar. 31, 2025
Accounting Policies [Abstract]  
Basis of Presentation and Principles of Consolidation
Basis of Presentation and Principles of Consolidation
The Company’s unaudited condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP) and applicable rules and regulations of the SEC regarding interim financial reporting. All intercompany balances and transactions have been eliminated upon consolidation. The unaudited interim condensed consolidated financial statements have been prepared on the same basis as the annual consolidated financial statements and reflect, in the opinion of management, all adjustments of a normal and recurring nature that are necessary for the fair presentation of the Company’s financial information. The unaudited condensed consolidated results of operations for the three months ended March 31, 2025 are not necessarily indicative of the results to be expected for the year ending December 31, 2025, or for any other future annual or interim period.
Certain information and footnote disclosures typically included in the Company’s annual consolidated financial statements have been condensed or omitted. As such, these unaudited interim condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and related notes included in the Annual Report on Form 10-K for the year ended December 31, 2024.
Use of Estimates
Use of Estimates
The preparation of the unaudited condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could materially differ from those estimates.
Segments
Segments
Operating segments are defined as components of an entity about which separate discrete information is available for evaluation by the chief operating decision maker (CODM) in deciding how to allocate resources and in assessing performance. The Company manages the business activities on a consolidated basis and operates as one reportable segment that constitutes all of the consolidated entity, which is the business of powering the immune system to transform lives by discovering and developing medicines for serious infectious diseases and cancer. Factors used in determining the reportable segment include the nature of the Company’s operating activities, the organizational and reporting structure, and the type of information regularly provided to the CODM to allocate resources and evaluate financial performance. The Company’s CODM is its Chief Executive Officer.
Cash Equivalents
Cash Equivalents
The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents, which consist of amounts invested primarily in money market funds and are stated at fair value.
Investments
Investments
Investments include available-for-sale debt securities and equity investments, which are carried at fair value.
Available-for-Sale Debt Securities
The Company’s valuations of marketable securities are generally derived from independent pricing services based on quoted prices in active markets for similar securities at period end. Generally, investments with original maturities beyond three months at the date of purchase and that mature at, or less than 12 months from, the unaudited condensed consolidated balance sheet date are considered short-term investments, with all others considered to be long-term investments. Unrealized gains and losses deemed temporary in nature are reported as a component of accumulated other comprehensive loss. The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity, which is included in interest income on the unaudited condensed consolidated statements of operations. The cost of securities sold is based on the specific identification method.
Equity Investments
The Company measures its investment in equity securities at fair value at each reporting date based on the market price at period end if it has a readily determinable fair value. Otherwise, the investments in equity securities are measured at cost less impairment, adjusted for observable price changes for identical or similar investments of the same issuer unless the Company has significant influence or control over the investee. Changes in fair value resulting from observable price changes are presented as change in fair value of equity investments, and changes in fair value resulting from foreign currency translation are included in other expense, net on the unaudited condensed consolidated statements of operations.
Restricted Cash and Cash Equivalents
Restricted Cash and Cash Equivalents
Restricted cash and cash equivalents primarily includes the $75.0 million milestone payment due upon VIR-5525 achieving “first in human dosing” by 2026, amounts that may need to be refunded to the Gates Foundation and money market funds to secure standby letters of credit and security deposits with financial institutions under lease agreements.
Research and Development Expenses
Research and Development Expenses
To date, research and development expenses have related primarily to discovery efforts and preclinical and clinical development of product candidates. Research and development expenses are recognized as incurred, and payments made prior to the receipt of goods or services to be used in research and development are capitalized until the goods or services are received. Research and development expenses include expenses related to license and collaboration agreements; contingent consideration from business acquisitions; personnel-related expenses, including salaries, benefits, and stock-based compensation for personnel contributing to research and development activities; expenses incurred under agreements with third-party contract manufacturing organizations, contract research organizations, and consultants; clinical costs, including laboratory supplies and costs related to compliance with regulatory requirements; and other allocated expenses, including expenses for rent, facilities maintenance, and depreciation and amortization.
The Company has acquired and may continue to acquire the rights to develop and commercialize new product candidates from third parties. Upfront payments and research and development milestone payments made in connection with acquired licenses or product rights are expensed as incurred, provided that they do not relate to a regulatory approval milestone or assets acquired in a business combination.
The Company’s expense accruals for clinical trials and manufacturing are based on estimates of contracted services provided by third-party vendors not yet billed. When billing terms under these contracts do not coincide with the timing of when the work is performed, the Company is required to make estimates of its outstanding obligations to those third parties as of the period end. The accrual estimates are based on a number of factors, including the Company’s knowledge of the research and development programs and clinical manufacturing activities, the status of the programs and activities, invoicing to date, and the provisions in the contracts. The Company obtains information regarding unbilled services directly from these service providers and performs procedures to support its estimates based on its internal understanding of the services provided to date. However, the Company may also be required to estimate these services based on information available to its internal clinical and manufacturing administrative staff if such information is not able to be obtained timely from its service providers
New Accounting Pronouncement Not Yet Adopted
New Accounting Pronouncement Not Yet Adopted
In December 2023, the Financial Accounting Standards Board (FASB) issued Accounting Standards Updates (ASU) No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which modifies the rules on income tax disclosures to require entities to disclose (1) specific categories in the rate reconciliation, (2) the income or loss from continuing operations before income tax expense or benefit (separated between domestic and foreign) and (3) income tax expense or benefit from continuing operations (separated by federal, state and foreign). ASU 2023-09 also requires entities to disclose their income tax payments to international, federal, state and local jurisdictions, among other changes. The guidance is effective for annual periods beginning after December 15, 2024. Early adoption is permitted. ASU 2023-09 should be applied on a prospective basis, but retrospective application is permitted. The Company is currently evaluating the impact the adoption of ASU 2023-09 may have on its annual consolidated financial statements and related disclosures.
In November 2024, the FASB issued ASU No. 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (ASU 2024-03), which requires entities to disclose specific information on the types of expenses included in the expense captions presented on the face of the income statement as well as disclosures about selling expenses. The guidance is effective for annual periods beginning after December 15, 2026 and interim periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. ASU 2024-03 should be applied on a prospective basis, but retrospective application is permitted. The Company is currently evaluating the impact the adoption of ASU 2024-03 may have on its consolidated financial statements and related disclosures.
Reclassification
Reclassification
Certain reclassifications have been made to prior period amounts on the Company’s condensed consolidated statements of operations to conform to the current period presentation and enhance comparability. As a result, certain amounts related to restructuring activities and long-lived assets impairment and disposal gains or losses, previously reflected in selling, general and administrative, were reclassified to restructuring, long-lived assets impairment and related charges, net. These reclassifications had no impact on previously reported total revenues, total operating expenses, or net loss.
Certain reclassifications have been made to prior period amounts on the Company’s condensed consolidated statements of cash flows to conform to the current period presentation and enhance comparability. As a result, certain amounts related to collaboration receivables, previously reflected in changes in operating assets and liabilities – receivable from collaboration, were reclassified to changes in operating assets and liabilities – prepaid assets and other current assets.
v3.25.1
Fair Value Measurements (Tables)
 3 Months Ended
Mar. 31, 2025
Fair Value Disclosures [Abstract]  
Schedule of Financial Assets Measured at Fair Value on a Recurring Basis
The following tables summarize the Company’s Level 1 and Level 2 financial assets measured at fair value on a recurring basis by level within the fair value hierarchy as of March 31, 2025 and December 31, 2024 (in thousands):
March 31, 2025
Valuation
Hierarchy		Amortized
Cost		Gross
Unrealized
Holding
Gains		Gross
Unrealized
Holding
Losses 		Aggregate
Fair Value
Assets:
Money market fundsLevel 1$168,828 $— $— $168,828 
U.S. government treasuriesLevel 2450,270 406 (10)450,666 
U.S. government agency bonds and discount notesLevel 267,991 36 (29)67,998 
Asset-backed securities Level 258,515 177 (1)58,691 
Corporate bondsLevel 2243,488 538 (3)244,023 
Equity securitiesLevel 1N/AN/AN/A10,724 
Total financial assets$989,092 $1,157 $(43)$1,000,930 
Reconciliation to cash, cash equivalents and investments on condensed consolidated balance sheet
Minus: Restricted cash equivalents invested in money market funds(18,957)
Plus: Cash deposits37,829 
Total cash, cash equivalents and investments$1,019,802 
December 31, 2024
Valuation
Hierarchy		Amortized
Cost		Gross
Unrealized
Holding
Gains		Gross
Unrealized
Holding
Losses 		Aggregate
Fair Value
Assets:
Money market fundsLevel 1$146,505 $— $— $146,505 
U.S. government treasuriesLevel 2588,794 722 (33)589,483 
U.S. government agency bonds and discount notesLevel 238,081 17 (19)38,079 
Asset-back securitiesLevel 251,038 220 (10)51,248 
Corporate bondsLevel 2252,935 529 (9)253,455 
Equity securitiesLevel 1N/AN/AN/A 4,350 
Total financial assets$1,077,353 $1,488 $(71)$1,083,120 
Reconciliation to cash, cash equivalents and investments on condensed consolidated balance sheet
Minus: Restricted cash equivalents invested in money market funds(20,281)
Plus: Cash deposits32,524 
Total cash, cash equivalents and investments$1,095,363 
Schedule of Estimated Fair Value of Significant Unobservable Inputs As of March 31, 2025, the Company recorded this $17.5 million as contingent consideration obligation, current on its unaudited condensed balance sheets and calculated the estimated fair value of the remaining clinical and regulatory milestones related to tobevibart using the following significant unobservable inputs:
Unobservable inputValue
Discount rates12.1%
Probability of achievement67.5%
As of March 31, 2025, the Monte Carlo simulation assumed a commercial product launch and associated discrete revenue forecasts, as well as the following significant unobservable inputs for the remaining commercial milestones related to tobevibart:
Unobservable inputValue
Volatility55.0%
Discount rate10.0%
Probability of achievement67.5%
Schedule of Changes in Estimated Fair Value of Contingent Consideration
The following table sets forth the changes in the estimated fair value of the Company’s contingent consideration obligations (in thousands):
Contingent
Consideration Obligation
Balance at December 31, 2024$40,110 
Changes in fair value1,030 
Balance at March 31, 2025$41,140 
v3.25.1
Collaboration and License Agreements (Tables)
 3 Months Ended
Mar. 31, 2025
Revenue Recognition [Abstract]  
Schedule of Asset Acquisition The following table summarizes the aggregate amount paid for the assets acquired by the Company in connection with the Sanofi Agreement as of the Acquisition Date (in thousands):
Upfront $100,000 
Equipment 1,150 
Deposits 2,580 
Transaction costs 4,612 
Total purchase consideration$108,342 
The total purchase price was allocated to the acquired assets based on their relative fair values, as of the Acquisition Date as follows (in thousands):
In-process research and development$102,836 
Property and equipment 1,119 
Prepaid expenses and other current assets (1)
3,975 
Assembled workforce412 
Total purchase consideration$108,342 
__________________________________________________________
(1) Includes acquired cash deposits primarily related to contract manufacturing agreements.
v3.25.1
Balance Sheet Components (Tables)
 3 Months Ended
Mar. 31, 2025
Balance Sheet Related Disclosures [Abstract]  
Schedule of Property and Equipment Net
Property and equipment, net consists of the following (in thousands). Depreciation expenses were $2.8 million and $4.4 million for the three months ended March 31, 2025 and 2024, respectively.
Useful life
(in years)		March 31,
2025		December 31,
2024
Leasehold improvements
8 - 12
$53,981 $53,992 
Laboratory equipment539,426 39,428 
Furniture and fixtures52,715 2,696 
Computer equipment32,621 2,778 
Construction in progressN/A1,808 1,074 
Property and equipment, gross100,551 99,968 
Less: accumulated depreciation(38,870)(36,785)
Total property and equipment, net$61,681 $63,183 
Schedule of Accrued and Other Liabilities
Accrued and other liabilities consist of the following (in thousands):
March 31,
2025		December 31,
2024
Research and development expenses$67,893 $29,225 
Payroll and related expenses11,611 31,165 
Excess funds payable under grant agreements11,177 11,589 
Operating lease liabilities, current7,925 7,752 
Other professional and consulting expenses2,068 2,268 
Other accrued expenses3,452 3,874 
Total accrued and other liabilities$104,126 $85,873 
v3.25.1
Stock-Based Awards (Tables)
 3 Months Ended
Mar. 31, 2025
Share-Based Payment Arrangement [Abstract]  
Schedule of Assumptions Used for Estimating the Fair Value of Stock Options Granted
The fair value of stock options granted to employees was estimated on the date of grant using the Black-Scholes option-pricing model with the following assumptions:
Three Months Ended March 31,
20252024
Expected term of options (in years)6.16.1
Expected stock price volatility
89.5% – 89.9%
89.2% – 89.3%
Risk-free interest rate
4.1% – 4.5%
4.3%
Expected dividend yield——
Schedule of Stock-based Compensation Expense The following table sets forth the total stock-based compensation expense for all awards granted to employees and non-employees and the ESPP in the unaudited condensed consolidated statements of operations (in thousands):
Three Months Ended March 31,
20252024
Research and development$7,005 $13,606 
Selling, general and administrative7,054 10,151 
Total stock-based compensation$14,059 $23,757 
v3.25.1
Net Loss Per Share (Tables)
 3 Months Ended
Mar. 31, 2025
Earnings Per Share [Abstract]  
Schedule of Basic and Diluted Net Loss Per Share
The following is a calculation of the basic and diluted net loss per share (in thousands, except share and per share data):
Three Months Ended March 31,
20252024
Net loss$(120,965)$(65,276)
Weighted-average shares outstanding, basic and diluted137,468,900135,280,648
Net loss per share, basic and diluted$(0.88)$(0.48)
Schedule of Potentially Dilutive Securities Not Included in the Diluted Per Share Calculations
Securities that could potentially dilute basic net loss per common share in the future that were not included in the computation of diluted net loss per common share because to do so would have been antidilutive for the periods presented were as follows:
Three Months Ended March 31,
20252024
Options issued and outstanding11,080,15912,018,822
Restricted shares subject to future vesting6,888,4624,521,874
Total17,968,62116,540,696
v3.25.1
Income Taxes (Tables)
 3 Months Ended
Mar. 31, 2025
Income Tax Disclosure [Abstract]  
Schedule of Income Tax Expense Benefit And Effective Tax Rate
The table below presents our loss before provision for income taxes, provision for income taxes and effective tax rate for the three months ended March 31, 2025 and 2024(in thousands):
Three Months Ended March 31,
20252024
Loss before provision for income taxes$(120,949)$(65,000)
Provision for income taxes$(16)$(276)
Effective tax rate— %(0.4 %)
v3.25.1
Segment Reporting (Tables)
 3 Months Ended
Mar. 31, 2025
Segment Reporting [Abstract]  
Schedule of Segment Reporting Information, by Segment
The segment revenue, segment profit or loss, and significant segment expenses regularly provided to CODM are summarized as follows (in thousands).
Three Months Ended
March 31,
20252024
Segment revenue$3,032 $56,376 
Less: Segment expenses (1)
Cost of revenue— 59 
Research and development
Contract manufacturing9,336 9,669 
Clinical costs20,606 11,607 
Personnel (2)
33,718 46,190 
Licenses, collaborations and contingent consideration36,591 5,696 
Other R&D (3)
18,394 26,963 
Selling, general and administrative (2)
23,944 36,321 
Restructuring, long-lived assets impairment and related charges, net(10)(48)
Plus: Other segment items (4)
18,582 14,805 
Segment and consolidated net loss$(120,965)$(65,276)
(1) Refer to Note 6 Balance Sheet Components for depreciation and amortization expenses included in segment expenses.
(2) Refer to Note 8 Stock-Based Awards for stock-based compensation expenses included in segment expenses.
(3) Other research and development expenses primarily includes non-personnel research expenses, allocated facility and IT expenses, IPR&D impairment, and depreciation expenses.
(4) Other segment items include change in fair value of equity investments, interest income, other expense, net, and provision for income taxes, all of which were presented on the condensed consolidated statements of operations.
Schedule of Revenue from External Customers by Geographic Areas
The following table summarizes segment revenues by geographic area (in thousands). The revenues attributed to foreign customers primarily include collaboration and contract revenues recognized under the Company’s collaboration agreements with GSK, contract revenue generated from clinical supplies provided to foreign companies, and license revenue from the Company’s collaboration with Brii Bio.
Three Months Ended
March 31,
Segment revenues attributed to:20252024
U.S. customers$1,238 $5,172 
Foreign customers
GSK(70)50,694 
Other1,864 510 
Total segment and consolidated revenue$3,032 $56,376 
v3.25.1
Organization (Details) - USD ($)
$ in Thousands
 1 Months Ended 3 Months Ended
Nov. 30, 2023
Mar. 31, 2025
Dec. 31, 2024
Organization Consolidation And Presentation Of Financial Statements [Line Items]      
Total cash, cash equivalents and investments   $ 1,019,802 $ 1,095,363
Restricted cash and cash equivalents   $ 94,400  
Sales Agreement | Common Stock      
Organization Consolidation And Presentation Of Financial Statements [Line Items]      
Percentage of commission rate from sale of shares (as a percent) 3.00%    
Issuance of common stock (in shares)   0  
Maximum      
Organization Consolidation And Presentation Of Financial Statements [Line Items]      
Aggregate offering price $ 300,000    
v3.25.1
Summary of Significant Accounting Policies (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2025
segment
Sep. 09, 2024
USD ($)
Summary of Significant Accounting Policies    
Number of reportable segments | segment 1  
Sanofi Agreement    
Summary of Significant Accounting Policies    
Milestone payment in escrow | $   $ 75.0
v3.25.1
Fair Value Measurements - Schedule of Financial Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($)
$ in Thousands
Mar. 31, 2025
Dec. 31, 2024
Mar. 31, 2024
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Aggregate Fair Value $ 273,571 $ 222,947 $ 160,711
Gross Unrealized Holding Gains 1,157 1,488  
Gross Unrealized Holding Losses (43) (71)  
Equity securities 10,700    
Amortized Cost 989,092 1,077,353  
Aggregate Fair Value 1,000,930 1,083,120  
Reconciliation to cash, cash equivalents and investments on condensed consolidated balance sheet      
Restricted cash and cash equivalents (94,400)    
Plus: Cash deposits 37,829 32,524  
Total cash, cash equivalents and investments 1,019,802 1,095,363  
Money market funds      
Reconciliation to cash, cash equivalents and investments on condensed consolidated balance sheet      
Restricted cash and cash equivalents (18,957) (20,281)  
Level 1 | Money market funds      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Amortized Cost 168,828 146,505  
Aggregate Fair Value 168,828 146,505  
Level 1 | Equity securities      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Equity securities 10,724 4,350  
Level 2 | U.S. government treasuries      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Amortized Cost 450,270 588,794  
Gross Unrealized Holding Gains 406 722  
Gross Unrealized Holding Losses (10) (33)  
Aggregate Fair Value 450,666 589,483  
Level 2 | U.S. government agency bonds and discount notes      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Amortized Cost 67,991 38,081  
Gross Unrealized Holding Gains 36 17  
Gross Unrealized Holding Losses (29) (19)  
Aggregate Fair Value 67,998 38,079  
Level 2 | Asset-backed securities      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Amortized Cost 58,515 51,038  
Gross Unrealized Holding Gains 177 220  
Gross Unrealized Holding Losses (1) (10)  
Aggregate Fair Value 58,691 51,248  
Level 2 | Corporate bonds      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Amortized Cost 243,488 252,935  
Gross Unrealized Holding Gains 538 529  
Gross Unrealized Holding Losses (3) (9)  
Aggregate Fair Value $ 244,023 $ 253,455  
v3.25.1
Fair Value Measurements - Additional Information (Details) - USD ($)
 3 Months Ended 12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Dec. 31, 2024
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] Prepaid expenses and other current assets   Prepaid expenses and other current assets
Accrued interest receivable $ 5,400,000   $ 5,000,000.0
Accrued interest receivable writeoff 0 $ 0  
Total net unrealized gains recorded in accumulated other comprehensive loss 1,100,000   1,400,000
Equity securities 10,700,000    
Unrealized gain (loss) on equity securities 6,382,000 $ (5,915,000)  
Contingent consideration obligation, current 17,500,000   16,060,000
Humabs      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Contingent consideration recognized $ 41,100,000   $ 40,100,000
Maximum      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Securities contractual term (in years) 2 years    
v3.25.1
Fair Value Measurements - Schedule of Estimated Fair Value of Significant Unobservable Inputs (Details) - Humabs
Mar. 31, 2025
Clinical and Regulatory Milestones | Discount rates  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Fair value contingent consideration measurement input (as a percent) 0.121
Clinical and Regulatory Milestones | Probability of achievement  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Fair value contingent consideration measurement input (as a percent) 0.675
Commercial Milestones | Discount rates  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Fair value contingent consideration measurement input (as a percent) 0.100
Commercial Milestones | Probability of achievement  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Fair value contingent consideration measurement input (as a percent) 0.675
Commercial Milestones | Volatility  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Fair value contingent consideration measurement input (as a percent) 0.550
v3.25.1
Fair Value Measurements - Schedule of Changes in Estimated Fair Value of Contingent Consideration (Details) - Level 3 - Contingent Consideration Liability
$ in Thousands
 3 Months Ended
Mar. 31, 2025
USD ($)
Contingent Consideration Obligation  
Balance at December 31, 2024 $ 40,110
Changes in fair value 1,030
Balance at March 31, 2025 $ 41,140
v3.25.1
Grant Agreements (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended
Jan. 13, 2022
Mar. 31, 2025
Mar. 31, 2024
Dec. 31, 2024
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]        
Accrued and other liabilities   $ 104,126   $ 85,873
Vaccinal Antibody Grant | Grant revenue        
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]        
Grant revenue   1,200 $ 1,900  
Vaccinal Antibody Grant | Gates Foundation        
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]        
Common stock shares purchased (in shares) 881,365      
Common stock, shares purchased price (in USD per share) $ 45.38      
Common stock, shares purchased, aggregate purchase price $ 40,000      
Common stock, shares issued, fair market value $ 28,500      
Closing stock price (in USD per share) $ 37.65      
Premium received $ 11,300      
Deferred revenue   10,400   11,100
Accrued and other liabilities   11,200   $ 11,600
Maximum | Human Immunodeficiency Virus ('HIV') Grant        
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]        
Grant awarded amount. maximum   $ 49,900    
v3.25.1
Collaboration and License Agreements - License Agreement with Sanofi (Details) - Sanofi Agreement
$ in Thousands
Sep. 09, 2024
USD ($)
engager
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]  
Number of oncology TCEs | engager 3
Upfront payment $ 100,000
Milestone payment in escrow 75,000
Maximum future development and regulatory milestone payments 323,000
Maximum commercial net sales-based milestone payments $ 1,490,000
Asset acquisition, period for execution of transaction (in years) 2 years
Payments for asset acquisitions $ 3,700
Transaction costs $ 4,612
Assembled Workforce  
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]  
Finite-lived intangible asset, estimated useful life (in years) 5 years
v3.25.1
Collaboration and License Agreements - Schedule of License Agreement, Assets Acquired (Details) - Sanofi Agreement
$ in Thousands
Sep. 09, 2024
USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]  
Upfront $ 100,000
Equipment 1,150
Deposits 2,580
Transaction costs 4,612
Total purchase consideration $ 108,342
v3.25.1
Collaboration and License Agreements - Schedule of Purchase Price (Details) - Sanofi Agreement
$ in Thousands
Sep. 09, 2024
USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]  
In-process research and development $ 102,836
Property and equipment 1,119
Prepaid expenses and other current assets 3,975
Assembled workforce 412
Total purchase consideration $ 108,342
v3.25.1
Collaboration and License Agreements - 2021 GSK Agreement (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]    
Total revenues $ 3,032 $ 56,376
Research and development 118,645 100,125
Contract revenue    
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]    
Total revenues $ 1,864 $ 52,191
v3.25.1
Collaboration and License Agreements - Alnylam Pharmaceuticals, Inc. (Details) - Alnylam Pharmaceuticals Inc - Alnylam Agreement
 1 Months Ended 3 Months Ended
Oct. 31, 2017
USD ($)
diseaseTarget
Mar. 31, 2025
USD ($)
Mar. 31, 2024
USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]      
Expenses incurred under agreement   $ 30,000,000.0 $ 0
Royalty payment obligation expiration period after first commercial sales (in years) 10 years    
Written notice period for termination of licensed program (in days) 90 days    
Written notice period to terminate licensed program for uncured material breach (in days) 60 days    
Written notice period to terminate licensed program for payment breach (in days) 30 days    
Written notice period to terminate licensed program if under challenge (in days) 30 days    
First Si R N A Product H B V      
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]      
Maximum number of other infectious disease targets selected by VirBio | diseaseTarget 4    
Maximum milestone payment for achievement of specified development and regulatory milestones $ 175,000,000 $ 145,000,000  
Maximum aggregate sales milestone payment $ 250,000,000    
v3.25.1
Balance Sheet Components - Additional Information (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Balance Sheet Related Disclosures [Abstract]    
Depreciation $ 2.8 $ 4.4
v3.25.1
Balance Sheet Components - Schedule of Property and Equipment Net (Details) - USD ($)
$ in Thousands
Mar. 31, 2025
Dec. 31, 2024
Property Plant And Equipment [Line Items]    
Property and equipment, gross $ 100,551 $ 99,968
Less: accumulated depreciation (38,870) (36,785)
Total property and equipment, net 61,681 63,183
Leasehold improvements    
Property Plant And Equipment [Line Items]    
Property and equipment, gross $ 53,981 53,992
Leasehold improvements | Minimum    
Property Plant And Equipment [Line Items]    
Useful life (in years) 8 years  
Leasehold improvements | Maximum    
Property Plant And Equipment [Line Items]    
Useful life (in years) 12 years  
Laboratory equipment    
Property Plant And Equipment [Line Items]    
Useful life (in years) 5 years  
Property and equipment, gross $ 39,426 39,428
Furniture and fixtures    
Property Plant And Equipment [Line Items]    
Useful life (in years) 5 years  
Property and equipment, gross $ 2,715 2,696
Computer equipment    
Property Plant And Equipment [Line Items]    
Useful life (in years) 3 years  
Property and equipment, gross $ 2,621 2,778
Construction in progress    
Property Plant And Equipment [Line Items]    
Property and equipment, gross $ 1,808 $ 1,074
v3.25.1
Balance Sheet Components - Schedule of Accrued and Other Liabilities (Details) - USD ($)
$ in Thousands
Mar. 31, 2025
Dec. 31, 2024
Balance Sheet Related Disclosures [Abstract]    
Research and development expenses $ 67,893 $ 29,225
Payroll and related expenses 11,611 31,165
Excess funds payable under grant agreements 11,177 11,589
Operating lease liabilities, current 7,925 7,752
Other professional and consulting expenses 2,068 2,268
Other accrued expenses 3,452 3,874
Total accrued and other liabilities $ 104,126 $ 85,873
Accrued and other liabilities Total accrued and other liabilities Total accrued and other liabilities
v3.25.1
Commitments and Contingencies (Details)
$ in Millions
Mar. 31, 2025
USD ($)
Tobevibart Agreements  
Commitments And Contingencies [Line Items]  
Unpaid noncancellable commitments $ 22
Elebsiran Agreement  
Commitments And Contingencies [Line Items]  
Unpaid noncancellable commitments $ 8
v3.25.1
Stock-Based Awards - Schedule of Assumptions Used for Estimating the Fair Value of Stock Options Granted (Details)
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Share-Based Payment Arrangement [Abstract]    
Expected term of options (in years) 6 years 1 month 6 days 6 years 1 month 6 days
Expected stock price volatility, minimum 89.50% 89.20%
Expected stock price volatility, maximum 89.90% 89.30%
Risk-free interest rate, minimum 4.10%  
Risk-free interest rate, maximum 4.50%  
Risk-free interest rate   4.30%
Expected dividend yield 0.00% 0.00%
v3.25.1
Stock-Based Awards - Schedule of Stock-based Compensation Expense (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Total stock-based compensation $ 14,059 $ 23,757
Research and development    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Total stock-based compensation 7,005 13,606
Selling, general and administrative    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Total stock-based compensation $ 7,054 $ 10,151
v3.25.1
Net Loss Per Share - Schedule of Basic and Diluted Net Loss Per Share (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Earnings Per Share [Abstract]    
Net loss $ (120,965) $ (65,276)
Weighted-average shares outstanding, basic (in shares) 137,468,900 135,280,648
Weighted-average shares outstanding, diluted (in shares) 137,468,900 135,280,648
Net loss per share, basic (in USD per share) $ (0.88) $ (0.48)
Net loss per share, diluted (in USD per share) $ (0.88) $ (0.48)
v3.25.1
Net Loss Per Share - Schedule of Potentially Dilutive Securities Not Included in Diluted Per Share Calculations (Details) - shares
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]    
Antidilutive shares excluded from calculation of diluted net (loss) income per share (in shares) 17,968,621 16,540,696
Options issued and outstanding    
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]    
Antidilutive shares excluded from calculation of diluted net (loss) income per share (in shares) 11,080,159 12,018,822
Restricted shares subject to future vesting    
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]    
Antidilutive shares excluded from calculation of diluted net (loss) income per share (in shares) 6,888,462 4,521,874
v3.25.1
Income Taxes - Schedule of Income (Loss) Before Income Taxes (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Income Tax Disclosure [Abstract]    
Loss before provision for income taxes $ (120,949) $ (65,000)
Provision for income taxes $ (16) $ (276)
Effective tax rate 0.00% (0.40%)
v3.25.1
Income Taxes - Additional Information (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Income Tax Disclosure [Abstract]    
Unrecognized tax benefits $ 18.5 $ 17.9
v3.25.1
Segment Reporting - Additional Information (Details)
 3 Months Ended
Mar. 31, 2025
segment
Segment Reporting [Abstract]  
Number of reportable segments 1
v3.25.1
Segment Reporting - Schedule of Segment Reporting Information, by Segment (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Segment Reporting Information [Line Items]    
Segment revenue $ 3,032 $ 56,376
Less: Segment expenses    
Cost of revenue 0 59
Research and development    
Selling, general and administrative 23,944 36,321
Restructuring, long-lived assets impairment and related charges, net (10) (48)
Net loss (120,965) (65,276)
Reportable Segment    
Research and development    
Contract manufacturing 9,336 9,669
Clinical costs 20,606 11,607
Personnel 33,718 46,190
Licenses, collaborations and contingent consideration 36,591 5,696
Other R&D 18,394 26,963
Plus: Other segment items 18,582 14,805
Net loss $ (120,965) $ (65,276)
v3.25.1
Segment Reporting - Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Revenues from External Customers and Long-Lived Assets [Line Items]    
Total segment and consolidated revenue $ 3,032 $ 56,376
U.S. customers    
Revenues from External Customers and Long-Lived Assets [Line Items]    
Total segment and consolidated revenue 1,238 5,172
Foreign customers | GSK    
Revenues from External Customers and Long-Lived Assets [Line Items]    
Total segment and consolidated revenue (70) 50,694
Foreign customers | Other    
Revenues from External Customers and Long-Lived Assets [Line Items]    
Total segment and consolidated revenue $ 1,864 $ 510