Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2021

Stock-Based Compensation

Schedule of compensation expense

	Six Months Ended June 30,
(In thousands)	2021		2020
Research and development	$	141	$	211
Sales and Marketing		74		—
General and administrative		2,823		3,681
Share-based compensation expense	$	3,038	$	3,892

Schedule of weighted-average assumptions used in valuing the stock options

	Six Months Ended June 30,
	2021		2020
Expected volatility	80.07	%	77.59	%
Range of expected volatility	77.37% to 81.5	%	75.84% to 81.63	%
Range of risk free interest rate	0.72% to 1.22	%	0.34% to 1.77	%
Expected term of option	6.27	years	6.03	years
Expected dividend yield	0.00	%	0.00	%

Schedule of stock option plans and of changes in options outstanding under the plans

		Weighted Average
	Number of Options	Exercise Price
Outstanding at December 31, 2020	16,746,238	$	2.71
Exercised	—	$	—
Granted	9,249,552	$	1.80
Expired	(334,000)	$	4.80
Forfeited	(881,250)	$	2.65
Cancelled	—	$	—
Outstanding at June 30, 2021	24,780,540	$	2.34
Vested and expected to vest at June 30, 2021	24,780,540	$	2.34
Exercisable at June 30, 2021	13,670,488	$	2.46