Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Schedule of Assumptions Used to Estimate Fair Value of Stock Option Awards

The fair value of each employee and non-employee stock option grant was estimated on the date of grant using the Black-Scholes option-pricing model based on the following assumptions:

	Three Months Ended March 31,
	2022	2021
Risk-free interest rate	1.7%	0.7%
Expected dividend yield	0.0%	0.0%
Expected term in years	5.9	6.0
Expected volatility	71.8%-72.5%	73.8%-86.8%

Schedule of Share Option Activity

The following table summarizes information and activity related to the Company’s stock options:

	Number of Stock Options	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (in years)	Total Intrinsic Value (in thousands)
Outstanding as of December 31, 2021	4,230,162	$	8.92	8.4	$	—
Options granted	2,188,700	1.93
Options forfeited	(391,106)	11.14
Options exercised	—	—
Options expired	(212,909)	9.26
Outstanding as of March 31, 2022	5,814,847	$	6.13	8.0	$	406
Options vested and exercisable	2,554,368	$	7.43	6.0	$	—

Schedule of RSU Information and Activity

The following table summarizes information and activity related to the Company’s RSUs:

	Number of Restricted Stock Units	Weighted Average Grant Date Fair Value Per Share
Outstanding at December 31, 2021	17,504	$	9.51
Granted	—	$	—
Vested	(365)	$	9.51
Outstanding at March 31, 2022	17,139	$	9.51
Vested as of March 31, 2022	365	$	9.51

Components of Stock-Based Compensation Expense

The following table summarizes total stock-based compensation expense recorded in the condensed consolidated statements of operations (in thousands):

	Three Months Ended March 31,
	2022		2021
Research and development	$	(448)	$	2,543
General and administrative	479		2,574
Total	$	31	$	5,117