The Company reports all financial assets and liabilities and nonfinancial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The authoritative guidance establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to measurements involving significant unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are as follows:

Level 1—Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

Level 2—Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted quoted prices for identical or similar assets or liabilities 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 related assets or liabilities.

Level 3—Inputs are unobservable inputs for the asset or liability. The level in the fair value hierarchy within which a fair value measurement in its entirety is based on the lowest-level input that is significant to the fair value measurement in its entirety.

The Company's cash and cash equivalents included Level 1 investments in treasury securities of $100.5 million and $129.1 million as of September 30, 2024 and December 31, 2023, respectively. These securities are classified as held-to-maturity and all have been purchased with original maturities of 90 days or less. Held-to-maturity debt securities are recorded at amortized cost in the financial statements.


	September 30, 2024
	Amortized Cost		Unrealized Gains		Unrealized Losses			Aggregate Fair Value
U.S. treasury securities	$	100,488	$	24	$	(1	)	$	100,511


	December 31, 2023
	Amortized Cost		Unrealized Gains		Unrealized Losses		Aggregate Fair Value
U.S. treasury securities	$	129,113	$	28	$	—	$	129,141

The Company measures the fair value of outstanding debt for disclosure purposes on a recurring basis. As of September 30, 2024 and December 31, 2023, total debt of $34.2 million and $33.9 million is reported at amortized cost, respectively. This outstanding debt is classified as Level 2 as it is not actively traded. The amortized cost of the outstanding debt approximates the fair value.

The Company measures the fair value of the unissued common stock warrants to be issued pursuant to the Hercules Loan Agreement (as defined in Note 5, Debt) using the Black-Scholes option pricing method. These are classified as Level 3 liabilities, with an overall value of less than $0.1 million as of September 30, 2024. The unissued warrants are remeasured at each reporting date following execution of the Hercules Loan Agreement. See Note 5, Debt, and Note 7, Stockholders' Equity, for additional information regarding the common stock warrants.

The financial statements as of September 30, 2024 and December 31, 2023 do not include any assets or liabilities that are measured at fair value on a nonrecurring basis.