v3.26.1
Fair Value Measurement
 3 Months Ended
Mar. 31, 2026
Fair Value Disclosures [Abstract]  
Fair Value Measurement Fair Value Measurement
Fair value is the price that could be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Fair value determination in accordance with applicable accounting guidance requires that a number of significant judgments be made. Additionally, fair value is used on a nonrecurring basis to evaluate assets for impairment or as required for disclosure purposes by applicable accounting guidance on disclosures about fair value of financial instruments. Depending on the nature of the assets and liabilities, various valuation techniques and assumptions are used when estimating fair value. The carrying amounts of certain of the Company’s financial instruments, including cash, prepaid expenses, tax incentive receivable and accounts payable, are shown at cost, which approximates fair value due to the short-term nature of these instruments.
The Company follows the provisions of FASB ASC Topic 820, Fair Value Measurement, for financial assets and liabilities measured on a recurring basis. The guidance requires fair value measurements be classified and disclosed in one of the following three categories:
Level 1:    Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities.
Level 2:    Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liabilities.
Level 3:    Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity).
The following fair value hierarchy table presents information about the Company’s financial assets measured and carried at fair value (amounts in thousands):
Fair value measurement at reporting date using
Quoted prices
in active markets for
identical assets
(Level 1)		Significant
other
observable inputs (Level 2)		Significant
unobservable inputs
(Level 3)
Total
March 31, 2026
Assets
Money Market fund$606 $— $— $606 
U.S. Treasury and government agency securities
$49,942 238,922 — 288,864 
Corporate debt securities— 178,002 — 178,002 
Commercial Paper— 9,834 — 9,834 
Municipal bonds— 4,553 — 4,553 
Total
$50,548 $431,311 $— $481,859 

Fair value measurement at reporting date using
Quoted prices
in active markets for
identical assets
(Level 1)		Significant
other
observable inputs (Level 2)		Significant
unobservable inputs
(Level 3)		Total
December 31, 2025
Assets
Money Market fund$23,970 $— $— $23,970 
U.S. Treasury and government agency securities59,842 247,890 — 307,732 
Corporate debt securities— 183,456 — 183,456 
Commercial Paper— 34,616 — 34,616 
Total$83,812 $465,962 $— $549,774 
We classify our investments in available-for-sale U.S. Treasury securities and the money market fund into Level 1 of the ASC Topic 820 hierarchy because fair values represent quoted market prices for identical or comparable instruments. The Company estimates the fair value of its U.S. government agency securities, corporate debt securities, commercial paper, and municipal bonds by taking into consideration valuations obtained from third-party pricing services. The pricing services utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities, issuer credit spreads; benchmark securities; prepayment/default projections based on historical data; and other observable inputs.
The following represents the amortized cost bases and fair values of the Company’s fixed income investments as of March 31, 2026 (amounts in thousands):

Amortized CostGross Unrealized Gains Gross Unrealized LossesFair Value
Money Market fund, included in Cash and cash equivalents$606 $— $— $606 
U.S. Treasury and government agency securities, included in:
Cash and cash equivalents$9,979 $— $(1)$9,978 
Short-term investments117,574 30 (50)117,554 
Long-term investments161,784 1 (453)161,332 
Total U.S. Treasury and government agency securities$289,337 $31 $(504)$288,864 
Corporate debt securities, included in:
Short-term investments$86,741 $65 $(36)$86,770 
Long-term investments91,453 83 (304)91,232 
Total Corporate debt securities$178,194 $148 $(340)$178,002 
Commercial paper, included in:
Short-term investments$9,841 $— $(7)$9,834 
Total Commercial paper$9,841 $— $(7)$9,834 
Municipal bonds, included in:
Long-term investments$4,586 $— $(33)$4,553 
Total Municipal bonds$4,586 $— $(33)$4,553 
In aggregate:
Investments above with no unrealized loss
$105,039 $179 $— $105,218 
Investments above with unrealized loss
$377,525 $— $(884)$376,641 
Total investments
$482,564 $179 $(884)$481,859 


At the end of March 31, 2026, the Company held approximately 73 debt securities, of which 52 were in an unrealized loss position as of the end of the period, with an aggregate fair value of $376.6 million. The Company has not recorded any allowance for credit losses as of March 31, 2026 as it believes the decline in fair value below amortized cost is not related to credit losses. These investments in an unrealized loss position were in this position for less than 12 months and there has been no change in the credit risk of such securities during the period. Securities are evaluated at the end of each reporting period for evidence of the credit-related impairment.
Gross unrealized gains and losses as of March 31, 2026 were $0.2 million and $0.9 million, respectively, recorded in accumulated other comprehensive (loss) income. On March 31, 2026, the Company entered into a Transaction Agreement and plan of merger with Eli Lilly (the “Transaction Agreement”), pursuant to which the Company will be acquired in a transaction expected to close in the third quarter of 2026, subject to the satisfaction of customary closing conditions including regulatory approvals and approval by the Company’s shareholders. The Transaction has not been determined to be probable as of March 31, 2026 for purposes of ASC 805, Business Combinations. Pursuant to the terms of the Transaction Agreement, the Company is required to liquidate its marketable securities portfolio and convert the proceeds to cash and cash equivalents prior to or upon closing the transaction. The Company’s obligation to convert these securities is contingent upon the closing of the Transaction Agreement. Accordingly, the Company has continued to classify its marketable securities as available-for-sale as of March 31, 2026, as the obligation to liquidate is contingent upon a closing that had not occurred as of the balance sheet date. Upon
completion of the transaction, any unrealized gains or losses currently recognized in the accumulated other comprehensive (loss) income will be reclassified into earnings at the time of sale.
The following represents the amortized cost bases and fair values of the Company’s investments and money market fund as of December 31, 2025 (amounts in thousands):
Amortized CostGross Unrealized Gains Gross Unrealized LossesFair Value
Money Market fund, included in Cash and cash equivalents$23,970 $— $— $23,970 
U.S. Treasury and government agency securities, included in:
Cash and cash equivalents$9,974 $1 $— $9,975 
Short-term investments134,625 73 (21)134,677 
Long-term investments163,141 27 (88)163,080 
Total U.S. Treasury and government agency securities$307,740 $101 $(109)$307,732 
Corporate debt securities, included in:
Short-term investments$63,847 $141 $— $63,988 
Long-term investments119,279 252 (63)119,468 
Total Corporate debt securities$183,126 $393 $(63)$183,456 
Commercial paper, included in:
Short-term investments$34,605 $11 $— $34,616 
Total Commercial paper$34,605 $11 $— $34,616 
In aggregate:
Investments above with no unrealized loss$309,888 $505 $— $310,393 
Investments above with unrealized loss239,553 — (172)239,381 
Total investments$549,441 $505 $(172)$549,774 

At the end of December 31, 2025, the Company held approximately 79 securities, of which 37 were in an unrealized loss position as of the end of the period, with an aggregate fair value of $239.4 million. The Company has not recorded any allowance for credit losses as of December 31, 2025 as it believes the decline in fair value below amortized cost is not related to credit losses. These investments in an unrealized loss position were in this position for less than 12 months and there has been no change in the credit risk of such securities during the period. The Company does not intend to sell its investments and it is not more likely than not that the Company will be required to sell the securities before recovery of the amortized cost basis of its debt securities. Securities are evaluated at the end of each reporting period for evidence of the credit-related impairment.