Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of restricted stock unit activities

	Restricted Stock Units			Weighted Average Grant Date Fair Value
Non-vested as of December 31, 2021		96,201		$	28.87
Granted		139,800			6.84
Forfeited		(6,100	)		6.90
Vested		(30,163	)		30.00
Non-vested as of March 31, 2022		199,738		$	13.95

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		674,600			6.82		-		-
Exercised		-			-		-		-
Forfeited		(38,684	)		11.87		-		-
Expired		(12,500	)		15.30		-		-
Outstanding as of March 31, 2022		1,980,055		$	16.05		8.83	$	-
Exercisable as of March 31, 2022		593,192		$	21.29		8.01	$	-

(1) Aggregate intrinsic value represents the difference between the exercise price of the option and the closing market price of the Company’s common stock on March 31, 2022. The intrinsic value of options exercised during the three months ended March 31, 2022 and 2021 was $0, respectively, as no options were exercised.

Schedule of total stock-based compensation costs

	Three Months Ended March 31,
	2022		2021
Restricted stock units	$	314	$	1,303
Stock options		1,565		1,437
Total	$	1,879	$	2,740

Schedule of stock-based compensation expense

	Three Months Ended March 31,
	2022		2021
Research and development	$	366	$	270
General and administrative		1,513		2,470
Total	$	1,879	$	2,740