Stock-Based Awards (Tables)

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Abstract]

Summary of Assumptions Used for Estimating the Fair Value of Stock Options Granted

The fair value of stock options granted to employees was estimated on the date of grant using the Black-Scholes option-pricing model with the following assumptions:

	Three Months Ended June 30,		Six Months Ended June 30,
	2023	2022	2023	2022
Expected term of options (in years)	5.5 - 6.1	5.3 - 6.1	5.5 - 6.1	5.3 - 6.1
Expected stock price volatility	99.6% - 101.5%	103.8% - 110.5%	99.6% - 101.5%	103.8% - 111.2%
Risk-free interest rate	3.5% - 3.9%	2.8% - 3.3%	3.4% - 4.1%	1.6% - 3.3%
Expected dividend yield	—	—	—	—

Summary of Stock-based Compensation Expense

The following table sets forth the total stock-based compensation expense for all awards granted to employees and non-employees and the ESPP in the unaudited condensed consolidated statements of operations:

	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
	(in thousands)
Research and development	$	17,112	$	14,069	$	30,465	$	27,184
Selling, general and administrative	13,507		13,030		25,635		25,219
Total stock-based compensation	$	30,619	$	27,099	$	56,100	$	52,403