Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of Total Compensation Expense

The total compensation expense recognized in the statements of operations associated with all the stock-based compensation awards granted by the Company is as follows (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
Research and development	$	1,069	$	535	$	2,066	$	948
General and administrative		886		727		1,789		1,199
Total	$	1,955	$	1,262	$	3,855	$	2,147

Summary of Stock Option Activity

The following table summarizes stock option activity under the Plan for the six months ended June 30, 2022:

	Number of Options			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value (thousands)
Outstanding as of December 31, 2021		5,822,373		$	7.17		8.27	$	33,275
Granted		1,504,465			8.47
Exercised		(276,943	)		3.86
Cancelled or forfeited		(468,869	)		8.03
Outstanding as of June 30, 2022		6,581,026		$	7.54		8.07	$	2,123,446
Vested or expected to vest as of June 30, 2022		6,581,026		$	7.54		8.07	$	2,123,446
Options exercisable as of June 30, 2022		2,532,151		$	5.02		6.65	$	1,981,985

Summary of Assumptions Used to Value Stock Options Granted to Participants Using Black-Scholes Option-Pricing

The fair value of each option award granted is estimated on the date of grant using the Black-Scholes option pricing model and the weighted average assumptions. The underlying assumptions used to value stock options granted to participants using the Black-Scholes option-pricing were as follows:

	Three Months Ended June 30,						Six Months Ended June 30,
	2022			2021			2022			2021
Risk-free interest rate	3.01% - 3.03%			1.03% - 1.07%			1.67 - 3.03%			0.88% - 1.07%
Expected dividend yield		0	%		0	%		0	%		0	%
Expected option term (in years) range	5.5 - 6.08			6.0 - 6.08			5.15 - 6.08			6.0 - 6.08
Expected stock price volatility	0.85%			69.76% - 70.03%			0.84% - 0.85%			69.76% - 73.30%