v3.26.1
Fair Value Measurements
6 Months Ended
Jun. 30, 2026
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 June 30, 2026 and December 31, 2025 (in thousands):
June 30, 2026
Valuation
Hierarchy
Amortized
Cost
Gross
Unrealized
Holding
Gains
Gross
Unrealized
Holding
Losses
Aggregate
Fair Value
Assets:
Money market fundsLevel 1$138,260 $— $— $138,260 
U.S. government treasuriesLevel 2441,125 42 (1,090)440,077 
U.S. government agency bonds and discount notesLevel 258,275 — (263)58,012 
Asset-backed securities Level 267,474 47 (44)67,477 
Corporate bondsLevel 2247,600 103 (309)247,394 
Equity securitiesLevel 1N/AN/AN/A4,133 
Total financial assets$952,734 $192 $(1,706)$955,353 
Reconciliation to cash, cash equivalents and investments on condensed consolidated balance sheet
Minus: Restricted cash equivalents invested in money market funds(7,923)
Plus: Cash deposits60,312 
Total cash, cash equivalents and investments$1,007,742 
December 31, 2025
Valuation
Hierarchy
Amortized
Cost
Gross
Unrealized
Holding
Gains
Gross
Unrealized
Holding
Losses
Aggregate
Fair Value
Assets:
Money market fundsLevel 1$86,607 $— $— $86,607 
U.S. government treasuriesLevel 2310,148 341 (3)310,486 
U.S. government agency bonds and discount notesLevel 245,773 (16)45,763 
Asset-back securitiesLevel 284,676 277 — 84,953 
Corporate bondsLevel 2156,160 499 (1)156,658 
Equity securitiesLevel 1N/AN/AN/A6,077 
Total financial assets$683,364 $1,123 $(20)$690,544 
Reconciliation to cash, cash equivalents and investments on condensed consolidated balance sheet
Minus: Restricted cash equivalents invested in money market funds(7,916)
Plus: Cash deposits98,962 
Total cash, cash equivalents and investments$781,590 
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 $5.6 million and $3.6 million as of June 30, 2026 and December 31, 2025, respectively. The Company did not write off any accrued interest receivables during the six months ended June 30, 2026 and 2025.
The Company recognized total net unrealized losses of $1.5 million and total net unrealized gains of $1.1 million in accumulated other comprehensive loss as of June 30, 2026 and December 31, 2025, respectively, on the its unaudited condensed consolidated balance sheet. The gross unrealized losses as of June 30, 2026 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 June 30, 2026, no securities have contractual maturities (or weighted average life for asset-backed securities) of longer than two years.
As of June 30, 2026, 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. Changes in fair value are recognized as other income in the unaudited condensed consolidated statement of operations.
Contingent Consideration
Contingent consideration primarily includes potential milestone payments in connection with the acquisition 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 June 30, 2026 and December 31, 2025. The estimated fair value of the contingent consideration related to the Humabs acquisition was determined by calculating the probability-weighted regulatory and commercial milestone payments based on the assessment of the likelihood and estimated timing that certain milestones would be achieved.
As of June 30, 2026, the Company calculated the estimated fair value of the remaining regulatory milestone related to tobevibart using the following significant unobservable inputs:
Unobservable inputValue
Discount rate14.0%
Probability of achievement85.5%
For the commercial milestones, the Company used a Monte Carlo simulation because of the availability of discrete revenue forecasts. As of June 30, 2026, 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
Volatility65.0%
Discount rate11.0%
Probability of achievement85.5%
The discount rate captures the credit risk associated with the payment of the contingent consideration when earned and due. As of June 30, 2026 and December 31, 2025, the estimated fair value of the contingent consideration related to the Humabs acquisition was $34.3 million and $34.1 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, 2025$34,100 
Changes in fair value240 
Balance at June 30, 2026$34,340