Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2018

Stock-Based Compensation

Schedule of stock-based compensation expense

	Year ended December 31,
	2018		2017
General and administrative	$	589,000	$	975,000
Research and development		507,000		735,000
	$	1,096,000	$	1,710,000

Schedule of stock option activity

		Options Outstanding
						Weighted
				Weighted-		Average
	Shares			Average		Remaining	Aggregate
	Available		Number	Exercise		Contractual	Intrinsic
	for Grant		of Shares	Price		Term (in years)	Value
Balance, December 31, 2017	3,842		59,666	$	855.30	6.72	$	0
Authorized	413,333		—
Granted	(335,405)		335,405	$	7.50
Exercised	—		—	$	—
Forfeitures	15,743		(15,743)	$	615.72
Cancelled	(2,249)
Balance, December 31, 2018	95,264		379,328	$	76.33	9.19	$	0
Vested or expected to vest, December 31, 2018			365,790	$	76.33	9.19	$	0
Exercisable at December 31, 2018			51,973	$	76.33	9.19	$	0

Schedule of information with respect to stock options outstanding and exercisable

Information with respect to stock options outstanding and exercisable at December 31, 2018 is as follows:

Exercise Price	Shares	Exercisable
$3.41 – $7.05	308,339	—
$16.35 – $97.50	50,555	32,060
$222.00 - $225.00	1,931	1,594
$348.00 – $597.00	4,931	4,777
$651.00 – $1,129.50	5,636	5,606
$1,992.00 - $2,268.00	7,585	7,585
$4,156.50 - $4,371.00	351	351
	379,328	51,973

Schedule of weighted-average assumptions used for estimating the fair value of the stock compensation granted

	Year ended December 31,
	2018			2017
Risk-free interest rate		2.84	%		2.09	%
Expected volatility		79.42	%		79.02	%
Expected term		5.94	years		5.98	years
Expected dividend yield		0	%		0	%
Weighted average grant date fair value	$	1.18		$	1.76