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Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2025

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation Expense

The following stock-based compensation expense was recognized for the periods indicated (in thousands):

									Three Months Ended March 31,
															2025						2024
Research and development															$	3,083					$	2,829
Selling, general and administrative															1,303						2,724
Total stock-based compensation expense															$	4,386					$	5,553

Valuation Assumptions Using the Black-Scholes Option-Pricing Model

The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model using the assumptions in the following table for options issued during the period indicated:

			Three Months Ended March 31,
			2025						2024
Expected dividend yield			0%						0%
Expected volatility			110.7% -115.6%						94.9% - 95.5%
Risk-free interest rate			4.0% - 4.5%						4.0% - 4.4%
Expected term			6.11 years						6.06 years

Schedule of Stock Options Roll Forward

The following table summarizes stock option activity during the three months ended March 31, 2025:

			Shares						Weighted- Average Exercise Price						Weighted-Average Remaining Contractual Term (Years)						Aggregate Intrinsic Value  (in thousands)
Outstanding, December 31, 2024			12,939,517						$	14.80					6.4
Granted			1,760,870						2.58
Exercised			—						—
Forfeited			(203,736)						9.97
Expired			(28,644)						19.11
Outstanding, March 31, 2025			14,468,007						$	13.37					6.6						$	—
As of March 31, 2025:
Exercisable			9,730,401						$	16.20					5.5						$	—
Vested and expected to vest			14,081,415						$	13.52					6.5						$	—

Schedule of RSU Activity

The following table summarizes RSU activity during the three months ended March 31, 2025:

			Shares						Weighted-Average Grant Date Fair Value
Outstanding, December 31, 2024			1,068,994						$	11.97
Granted			315,670						2.60
Vested			(379,817)						11.40
Forfeited			(49,198)						12.04
Outstanding, March 31, 2025			955,649						$	9.10

Stock Option Additional Information [Table]

The following table summarizes additional information on stock options (in thousands, except per

share amounts):

									Three Months Ended March 31,
															2025						2024
Weighted-average fair value per share of stock options granted															$	2.23					$	14.17
Total intrinsic value of stock options exercised															$	—					$	1,918
Total cash received for stock options exercised															$	—					$	2,636
Total grant date fair value of stock options vested															$	6,118					$	3,903

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Tabular disclosure of allocation of amount expensed and capitalized for award under share-based payment arrangement to statement of income or comprehensive income and statement of financial position. Includes, but is not limited to, corresponding line item in financial statement.

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Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.

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