Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Payments (Tables)

Stock-Based Payments (Tables)

9 Months Ended

Sep. 30, 2022

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

A summary of the status of stock options as of December 31, 2021 and September 30, 2022 and changes during the nine months ended September 30, 2022 is presented below:


								Aggregate
				Weighted		Remaining		Intrinsic
				Average		Contractual		Value
	Shares			Exercise Price		Life (in years)		(in thousands)
Outstanding at December 31, 2021		665,727		$	82.70	7.2		$	4,936
Granted		911,336			30.94
Exercised		(3,770	)		0.40
Cancelled		(26,103	)		87.80
Outstanding at September 30, 2022		1,547,190		$	51.76		4.5	$	—
Exercisable at September 30, 2022		1,179,506		$	56.28		2.9	$	—

Summary of Status of Restricted Stock Units

A summary of the status of restricted stock units and restricted stock awards as of December 31, 2021 and September 30, 2022 and changes during the nine months ended September 30, 2022 is presented below:


	Shares
	Subject to
	Restricted Stock
	Units and			Weighted
	Restricted Stock			Average Grant
	Awards			Date Fair Value
Outstanding at December 31, 2021		268,749		$	65.21
Granted		383,523			14.41
Vested		(83,622	)		72.97
Forfeited		(47,334	)		55.15
Outstanding at September 30, 2022		521,316		$	28.83

Schedule of Weighted-Average Assumptions used in Black-Scholes Option-Pricing Model

The fair value of each stock option granted was estimated on the date of grant using the Black-Scholes option-pricing model based on the following weighted-average assumptions:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2022			2021			2022			2021
Weighted-average risk-free interest rate		3.60	%		1.12	%		2.85	%		0.87	%
Expected dividend yield		—	%		—	%		—	%		—	%
Expected option term (in years)		5.79			6.06			5.88			6.01
Volatility		83.27	%		81.24	%		82.18	%		81.88	%

Summary of Stock-based Compensation Expense for Stock Options and Restricted Stock Units

The following table summarizes the stock-based compensation expense for stock options and restricted stock units granted to employees and non-employees recorded in the Company’s condensed consolidated statements of operations:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Research and development	$	1,496	$	1,485	$	4,324	$	4,260
General and administrative		1,459		611		4,183		3,219
Total stock-based compensation expense	$	2,955	$	2,096	$	8,507	$	7,479