Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Payments (Tables)

Stock-Based Payments (Tables)

9 Months Ended

Sep. 30, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of status of stock options and changes during the period

A summary of the status of stock options as of December 31, 2018 and September 30, 2019 and changes during the nine months ended September 30, 2019 is presented below:

								Aggregate
				Weighted		Remaining		Intrinsic
				Average		Contractual		Value
	Shares			Exercise Price		Life (in years)		(in thousands)
Outstanding at December 31, 2018		3,732,643		$	9.88	7.9		$	1,694
Granted		1,107,000			6.73
Exercised		(7,780	)		6.48
Cancelled		(180,613	)		10.02
Outstanding at September 30, 2019		4,651,250		$	9.13		7.8	$	9,419
Exercisable at September 30, 2019		2,085,000		$	9.15		6.8	$	4,591

Summary of status of restricted stock units and changes during the period

A summary of the status of restricted stock units as of December 31, 2018 and September 30, 2019 and changes during the nine months ended September 30, 2019 is presented below:

				Weighted
				Average Grant
	Shares			Date Fair Value
Outstanding at December 31, 2018		—		$	—
Granted		1,145,625			6.77
Vested		—			—
Forfeited		(36,934	)		6.71
Outstanding at September 30, 2019		1,108,691		$	6.77

Schedule of weighted-average assumptions used in Black-Scholes option-pricing model

The fair value of each stock option granted was estimated on the date of grant using the Black-Scholes option-pricing model based on the following weighted-average assumptions:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2019			2018			2019			2018
Weighted-average risk-free interest rate		1.88	%		2.87	%		2.46	%		2.49	%
Expected dividend yield		—	%		—	%		—	%		—	%
Expected option term (in years)		6.08			6.08			6.02			6.03
Volatility		89.91	%		89.71	%		91.49	%		90.34	%

Summary of stock-based compensation expense for stock options granted to employee and non-employees

The following table summarizes the stock-based compensation expense for stock options and restricted stock units granted to employees and non-employees recorded in the Company’s condensed consolidated statements of operations:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2019		2018		2019		2018
Research and development	$	874	$	550	$	2,490	$	1,785
General and administrative		1,515		987		4,133		3,192
Total stock-based compensation expense	$	2,389	$	1,537	$	6,623	$	4,977