Stock-based Compensation (Tables)

9 Months Ended

Sep. 30, 2020

Share-based Payment Arrangement [Abstract]

Schedule of fair value of options granted

	Employee			Non-Employee
Expected volatility		88.1-91.5	%		N/A
Expected dividend yield		—			N/A
Expected term (in years)		5			N/A
Risk-free interest rate		0.11-0.26	%		N/A

Schedule of stock option activity

	Number of Options			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value (1)
Outstanding at December 31, 2019		136,489		$	28.00		3.9	$	—
Granted		300,206		$	1.94		4.8	$	—
Exercised		—		$	—		—	$	—
Forfeited		(9,125	)	$	—		—	$	—
Expired		—		$	—		—	$	—
Outstanding at September 30, 2020		427,570		$	10.25		3.9	$	—
Exercisable at September 30, 2020		115,655		$	25.39		2.5	$	—

(1) The aggregate intrinsic value in the table was calculated based on the difference between the estimated fair market value of the Company’s stock and the exercise price of the underlying options. The estimated stock values used in the calculation were $1.88 and $11.00 per share for the nine months ended September 30, 2020 and the year ended December 31, 2019, respectively.

Schedule of summarizes restricted stock unit activity

	Number of Units			Weighted Average Grant-Date Fair Value Per Unit
Outstanding as of December 31, 2019		5,877		$	30.28
Granted		30,738		$	1.97
Vested		(4,543	)	$	1.42
Forfeited		—		$	—
Outstanding as of September 30, 2020		32,072		$	4.05

Schedule of stock-based compensation expense

	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Research and development	$	2	$	1	$	7	$	11
General and administrative		160		203		446		664
Total stock-based compensation expense	$	162	$	204	$	453	$	675