STOCKHOLDERS' EQUITY (Tables)

9 Months Ended

Sep. 30, 2023

STOCKHOLDERS' EQUITY [Abstract]

Stock Option Activity

A summary of the stock option activity is presented in the table below:

	Number of Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value
Outstanding at December 31, 2022		19,427,755		$	3.69		8.68	$	378
Granted		10,138,730			1.79
Exercised		(127,799	)		2.79
Forfeited		(5,816,858	)		3.76
Outstanding at September 30, 2023		23,621,828		$	2.86		8.46	$	1,129
Options exercisable at September 30, 2023		6,311,402		$	3.98		6.38	$	286
Vested and expected to vest at September 30, 2023		19,261,890		$	2.96		8.29	$	916

RSU Activity

A summary of the RSU activity is presented in the table below:

	Number of Shares Underlying RSUs			Weighted Average Grant-Date Fair Value
Outstanding non-vested RSUs at December 31, 2022		2,018,449		$	8.41
Granted		491,320			1.76
Vested		(1,655,978	)		8.56
Forfeited		(213,117	)		7.09
Outstanding non-vested RSUs at September 30, 2023		640,674		$	3.39

Stock-Based Compensation

The Company’s stock-based compensation is allocated to the following operating expense categories as follows:

	Three months ended September 30,				Nine months ended September 30,
	2023		2022		2023		2022
Research and development	$	479	$	1,114	$	2,531	$	3,460
Selling, general and administrative		662		2,929		4,383		3,639
Total stock-based compensation	$	1,141	$	4,043	$	6,914	$	7,099