Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2019

Stock-Based Compensation

Schedule of stock option activity

		Options Outstanding
	Shares		Weighted-
	Available	Number of	Average
	for Grant	Shares	Exercise Price
Balances at December 31, 2018	—	825,205	$	12.15
Additional shares reserved	763,973	—		—
Options granted	(696,874)	696,874		8.52
Options exercised	—	(11,884)		2.89
Options cancelled	129,883	(129,883)		11.67
Balances at December 31, 2019	196,982	1,380,312	$	10.06

Schedule of the status of options

		Weighted-		Weighted-
		Average		Average
	Number of	Exercise		Contractual	Aggregate
	Options	Price		Term (Years)	Intrinsic Value
					(in thousands)
Options outstanding	1,380,312	$	10.06	7.89	$	258
Options vested and expected to vest	1,380,312	$	10.06	7.89	$	258
Options vested and exercisable	699,519	$	10.48	6.72	$	258

Schedule of stock-based compensation expense related to stock options

	Twelve Months Ended
	December 31,
	2019		2018
Research and development	$	662	$	461
General and administrative		1,266		1,065
Total	$	1,928	$	1,526

Options

Stock-Based Compensation

Schedule of fair value of the options granted estimated using assumptions

	Year Ended
	December 31,
	2019	2018
Expected term (in years)	6.25	6.25 - 9.7
Expected volatility	79% - 95%	77% - 84%
Risk-free interest-rate	1.59% - 2.67%	2.22% - 3.01%
Dividend yield	0%	0%

Number of shares excess granted under the 2014 Plan | Options

Stock-Based Compensation

Schedule of fair value of the options granted estimated using assumptions

	Year Ended December 31,
	2018
Expected term (in years)	6.25
Expected volatility	77% - 79%
Risk-free interest-rate	2.22% - 2.99%
Dividend yield	0%