Stock-Based Compensation Plan (Tables)

12 Months Ended

Dec. 31, 2020

Stock-Based Compensation Plan

Schedule of share-based payment award, stock options, valuation assumptions

For stock options granted during 2020 and 2019 the following weighted average assumptions were used in determining fair value:

	2020		2019
Risk-free interest rate	0.50	%	2.23	%
Expected volatility	122	%	126	%
Expected term in years	6.0		6.0
Dividend yield	—	%	—	%

Schedule of option activity under stock-based compensation plans

Option activity under the Plans for the year ended December 31, 2020 was as follows (in thousands, except as noted):

				Weighted
		Weighted-		Average
		Average		Remaining	Aggregate
		Exercise		Contractual	Intrinsic
	Options	Price		Term	Value
		(per share)		(in years)
Year Ended December 31, 2020
Outstanding at December 31, 2019	68	$	68.56	7.7	$	—
Granted	211		5.01	9.4
Forfeited	(4)		7.19
Expired	(1)		28.67
Outstanding at December 31, 2020	274	$	20.57	8.7	$	3,750
Vested and expected to vest December 31, 2020	238	$	22.66	8.7	$	—
Exercisable at December 31, 2020	66	$	63.95	7.2	$	3,070

Option activity under the Plans for the year ended December 31, 2019 was as follows (in thousands, except as noted):

				Weighted
		Weighted-		Average
		Average		Remaining	Aggregate
		Exercise		Contractual	Intrinsic
	Options	Price		Term	Value
		(per share)		(in years)
Year Ended December 31, 2019
Outstanding at December 31, 2018	37	$	112.60	7.5	$	—
Granted	35		18.40	9.2
Forfeited	(3)		36.68
Expired	(1)		61.18
Outstanding at December 31, 2019	68	$	68.56	7.7	$	—
Vested and expected to vest December 31, 2019	58	$	76.12	7.4	$	—
Exercisable at December 31, 2019	26	$	138.77	5.5	$	—