Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of restricted stock unit, or RSU, activities

	Restricted Stock Units			Weighted Average Grant Date Fair Value
Non-vested as of December 31, 2021		96,201		$	28.87
Granted		178,425			6.08
Forfeited		(18,800	)		13.66
Vested		(51,388	)		21.67
Non-vested as of September 30, 2022		204,438		$	12.19

Schedule of stock option activities

	Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value (1)
Outstanding as of December 31, 2021		1,356,639		$	20.51		8.59	$	1
Granted		769,500			6.43		-		-
Exercised		-			-		-		-
Forfeited		(234,078	)		15.70		-		-
Expired		(29,703	)		14.79		-		-
Outstanding as of September 30, 2022		1,862,358		$	15.38		8.00	$	-
Vested and expected to vest at September 30, 2022		1,862,358		$	15.38		8.00		-
Exercisable as of September 30, 2022		757,332		$	20.51		6.76	$	-

Schedule of total stock-based compensation costs

	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2022		2021		2022		2021
Restricted stock units	$	287	$	1,307	$	991	$	3,970
Stock options		1,150		1,409		4,267		4,484
Total	$	1,437	$	2,716	$	5,258	$	8,454

Schedule of stock-based compensation expense

	For the Three Months ended September 30,				For the Nine Months Ended September 30,
	2022		2021		2022		2021
Research and development	$	361	$	392	$	1,150	$	1,114
General and administrative		1,076		2,324		4,108		7,340
Total	$	1,437	$	2,716	$	5,258	$	8,454