Stock Compensation (Tables)

3 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Summary of Share-based Payment Arrangement, Expensed and Capitalized, Amount

The following tables summarize the stock-based compensation expense for stock options and restricted stock awards granted to employees and nonemployees that was recorded in the Company’s statements of operations and comprehensive loss for the three months ended March 31, 2022 and 2021.

	Three Months Ended March 31,
	2022		2021
Research and development	$	902	$	60
General and administrative		760		344
Total stock-based compensation expense	$	1,662	$	404

	Three Months Ended March 31,
	2022		2021
Employees	$	1,014	$	399
Nonemployees		648		5
Total stock-based compensation expense	$	1,662	$	404

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The fair value of stock options granted during the three months ended March 31, 2022 and 2021 was estimated using the Black-Scholes option pricing model based on the following weighted-average assumptions.

	Three Months Ended March 31,
	2022	2021
Expected term (in years)	6.0 – 6.1	6.0 – 6.1
Expected volatility	75.8%	76.3% – 76.4%
Risk-free rate	1.8% –1.9%	0.6% – 0.8%
Dividend yield	—	—

Summary of Share-based Compensation Arrangements by Share-based Payment Award

Stock option activity under the 2017 EIP and 2021 EIP was as follows:

	NUMBER OF OPTIONS			WEIGHTED- AVERAGE EXERCISE PRICE PER SHARE		WEIGHTED- AVERAGE REMAINING CONTRACTUAL LIFE (YEARS)		AGGREGATE INTRINSIC VALUE (000s)
Balance – December 31, 2021		2,924,521		$	5.62		9.11	$	61,712
Granted		588,002			21.08
Exercised		(17,946	)		3.65
Cancelled and forfeited		—			—
Outstanding as of March 31, 2022		3,494,577			8.23		9.03	$	53,356
Options exercisable as of March 31, 2022		672,992			3.47		8.72	$	13,472
Vested and expected to vest as of March 31, 2022		3,494,577		$	8.23		9.03	$	53,356

Summary of Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity

The following table shows RSU activity for the period ending March 31, 2022.

	NUMBER OF OPTIONS			WEIGHTED- AVERAGE GRANT DATE FAIR VALUE PER SHARE
Unvested balance at December 31, 2021		77,719		$	23.99
Granted		—			—
Vested		(19,429	)		23.99
Cancelled and forfeited		—			—
Unvested balance at March 31, 2022		58,290			8.23