Equity-based Compensation (Tables)

12 Months Ended

Dec. 31, 2024

Share-Based Payment Arrangement [Abstract]

Schedule of Stock-Based Compensation Expense

Stock‑based compensation expense by classification within the consolidated statements of operations and comprehensive loss is as follows (in thousands):

	Years Ended December 31,
	2024		2023		2022
Research and development	$	47,944	$	46,356	$	53,956
General and administrative		38,623		34,672		43,991
Total	$	86,567	$	81,028	$	97,947

Fair Value of Each Option Issued to Employees Estimated Using Black-Scholes Option-Pricing Model

The fair value of each option issued to employees was estimated at the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions:

	Years Ended December 31,
	2024			2023			2022
Options granted		1,566,536			1,860,485			1,492,589
Weighted-average exercise price	$	62.40		$	45.47		$	60.19
Weighted-average grant date fair value	$	38.63		$	28.39		$	38.54
Assumptions:
Expected volatility		63.9	%		65.1	%		70.2	%
Expected term (in years)		6.0			6.0			6.0
Risk-free interest rate		4.2	%		4.1	%		2.6	%
Expected dividend yield		0.0	%		0.0	%		0.0	%

Summary of Stock Option Activity

The following table summarizes stock option activity under the Company’s equity award plans (intrinsic value in thousands):

	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding at December 31, 2023		7,204,372		$	55.05		6.7	$	115,681
Granted		1,566,536			62.40
Exercised		(900,136	)		33.80
Cancelled or forfeited		(581,889	)		69.92
Outstanding at December 31, 2024		7,288,883		$	58.07		6.6	$	14,050
Exercisable at December 31, 2024		4,851,838		$	58.64		5.5	$	14,050
Vested and expected to vest at December 31, 2024		7,288,883		$	58.07		6.6	$	14,050

Summary of Restricted Stock Activity

The following table summarizes the restricted stock unit activity under the Company’s equity award plans:

	Shares			Weighted- Average Grant Date Fair Value
Unvested balance at December 31, 2023		1,781,415		$	61.00
Granted		1,284,894			60.26
Vested		(450,701	)		70.13
Cancelled or forfeited		(217,965	)		57.41
Unvested balance at December 31, 2024		2,397,643		$	59.21