Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Assumptions Used to Value Stock Options Granted

The assumptions that the Company used in Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted for the years ended December 31, 2021 and 2020 were as follows:

	2021	2020
Risk-free interest rate	0.88%	0.46%
Expected term (in years)	5.1 - 6.3	5.5 - 6.1
Expected volatility	77.7% - 93.0%	74.6% - 76.6%
Expected dividend yield	0.0%	0.0%

Summary of Activity of Stock Options

The following table summarizes the activity of the Company’s stock options under the 2021 Plan for the year ended December 31, 2021:

	SHARES			WEIGHTED- AVERAGE EXERCISE PRICE		WEIGHTED- AVERAGE REMAINING CONTRACTUAL TERM (in years)		AGGREGATE INTRINSIC VALUE (in thousands)
Outstanding as of December 31, 2020		1,053,874		$	1.51		7.5	$	4,964
Granted		2,602,643			14.49
Exercised		(155,821	)		1.21
Cancelled or forfeited		(211,987	)		13.24
Expired		(23,939	)		12.18
Outstanding as of December 31, 2021		3,264,770		$	11.04		8.4	$	7,228
Options exercisable as of December 31, 2021		846,024		$	4.03		6.7	$	5,589
Options vested or expected to vest as of December 31, 2021		3,264,770		$	11.04		8.4	$	7,228

Summary of Total Stock-Based Compensation Expense

Total stock-based compensation expense recorded as research and development and general and administrative expenses, respectively, for employees, directors and non-employees during the years ended December 31, 2021 and 2020 is as follows (in thousands):