Stock Compensation (Tables)

6 Months Ended

Jun. 30, 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, restricted stock awards, and restricted stock units granted to employees and nonemployees and for ESPP stock-based compensation that was recorded in the Company’s condensed statements of operations and comprehensive loss for the three and six months ended June 30, 2022 and 2021.

	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
Research and development	$	1,069	$	233	$	1,971	$	293
General and administrative		956		480		1,716		824
Total stock-based compensation expense	$	2,025	$	713	$	3,687	$	1,117

	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
Employees	$	1,325	$	703	$	2,339	$	1,102
Nonemployees		700		10		1,348		15
Total stock-based compensation expense	$	2,025	$	713	$	3,687	$	1,117

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

The fair value of stock options granted during the three and six months ended June 30, 2022 and 2021 was estimated using the Black-Scholes option pricing model based on the following weighted-average assumptions.

	Three Months Ended June 30,		Six Months Ended June 30,
	2022	2021	2022	2021
Expected term (in years)	5.5 – 6.1	5.5 – 6.1	5.5 – 6.1	5.5 – 6.1
Expected volatility	75.8% – 76.5%	76.3% – 76.6%	75.8% – 76.5%	76.3% – 76.6%
Risk-free rate	2.8% – 3.1%	1.0% – 1.1%	1.8% – 3.1%	0.6% – 1.1%
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)
Outstanding as of December 31, 2021		2,924,521		$	5.62		9.11	$	61,712
Granted		901,552			19.32
Exercised		(30,587	)		3.68
Cancelled and forfeited		—			—
Outstanding as of June 30, 2022		3,795,486			8.89		8.85		23,764
Options exercisable as of June 30, 2022		1,038,639			5.41		8.51		8,905
Vested and expected to vest as of June 30, 2022		3,795,486			8.89		8.85		23,764

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

The following table shows RSU activity for the period ending June 30, 2022.

	NUMBER OF SHARES			WEIGHTED- AVERAGE GRANT DATE FAIR VALUE PER SHARE
Unvested balance at December 31, 2021		77,719		$	23.99
Granted		15,000			15.46
Vested		(38,859	)		23.99
Cancelled and forfeited		—			—
Unvested balance at June 30, 2022		53,860			21.62