Stockholders' Equity And Stock-Based Compensation Expense (Tables)

6 Months Ended

Jun. 30, 2020

Stockholders' Equity And Stock-Based Compensation Expense [Abstract]

Common Stock Outstanding and Stockholders' Equity

	Common Stock	Stockholders' equity (in thousands)
Balance at December 31, 2018	17,219,300	$	19,628
Non-cash stock-based compensation for:
Stock options for employees	—		342
Stock options for non-employees	—		2
Issuance costs from sale 2018 sale of common stock and warrants	—		(60)
Net loss	—		(1,359)
Balance at March 30, 2019	17,219,300	$	18,553
Non-cash stock-based compensation for:
Stock options for employees	—		328
Stock options for non-employees	—		1
Net loss	—		(1,059)
Balance at June 30, 2019	17,219,300	$	17,823
Balance at December 31, 2019	21,841,810	$	22,099
Non-cash stock-based compensation for:
Stock options for employees	—		261
Stock options for non-employees	—		9
Proceeds from exercise of common stock warrants	2,888,092		3,613
Net loss	—		(1,150)
Balance at March 30, 2020	24,729,902	$	24,832
Non-cash stock-based compensation for:
Stock options for employees	—		249
Stock options for non-employees	—		3
Proceeds from exercise of common stock warrants	189,431		236
Net loss	—		(1,136)
Balance at June 30, 2020	24,919,333	$	24,184

Stock Options And Unvested Performance Award Outstanding Activity

	Stock Options	Performance Awards
Outstanding as of December 31, 2019	3,210,965	138,055
Options granted	25,000	—
Options exercised	—	—
Options forfeited/canceled	(70,093)	—
Outstanding as of June 30, 2020	3,165,872	138,055

Non-Cash Stock-Based Compensation Expenses

	Three months ended				Six months ended
	June 30,				June 30,
	2020		2019		2020		2019
Research and development	$	111	$	135	$	226	$	272
General and administrative		141		194		296		401
Total non-cash stock-based compensation expense	$	252	$	329	$	522	$	673