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Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 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 June 30,												Six Months Ended June 30,
			2025						2024						2025						2024
Research and development			$	2,237					$	3,264					$	5,320					$	6,093
Selling, general and administrative			1,453						3,387						2,756						6,111
Total stock-based compensation expense			$	3,690					$	6,651					$	8,076					$	12,204

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:

			Six Months Ended June 30,
			2025						2024
Expected dividend yield			0%						0%
Expected volatility			110.7% - 115.6%						94.9% - 114.3%
Risk-free interest rate			3.9% - 4.5%						4.0% - 4.7%
Expected term			6.11 years						6.06 years

Schedule of Stock Options Roll Forward

The following table summarizes stock option activity during the six months ended June 30, 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			2,093,044						2.40
Exercised			—						—
Forfeited			(276,402)						9.55
Expired			(96,765)						22.04
Outstanding, June 30, 2025			14,659,394						$	13.08					6.4						$	—
As of June 30, 2025:
Exercisable			10,148,089						$	15.81					5.4						$	—
Vested and expected to vest			14,304,994						$	9.43					6.3						$	—

Schedule of RSU Activity

The following table summarizes RSU activity during the six months ended June 30, 2025:

			Shares						Weighted-Average Grant Date Fair Value
Outstanding, December 31, 2024			1,068,994						$	11.97
Granted			349,420						2.49
Vested			(491,146)						10.71
Forfeited			(78,029)						10.25
Outstanding, June 30, 2025			849,239						$	8.96

Stock Option Additional Information [Table]

The following table summarizes additional information on stock options (in thousands, except per share amounts):

									Six Months Ended June 30,
															2025						2024
Weighted-average fair value per share of stock options granted															$	2.03					$	12.99
Total intrinsic value of stock options exercised															$	—					$	2,615
Total cash received for stock options exercised															$	—					$	3,117
Total grant date fair value of stock options vested															$	9,494					$	7,344

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Disclosure of the number and weighted-average grant date fair value for restricted stock and restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year.

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