CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Operating expenses:
Research and development	$ 3,049	$ 3,467	$ 11,464	$ 7,909
General and administrative	3,494	2,865	10,626	5,781
Total operating expenses	6,543	6,332	22,090	13,690
Loss from operations	(6,543)	(6,332)	(22,090)	(13,690)
Other income (expense):
Interest income	453	427	1,523	621
Other expense		(1)	(3)	(1)
Total other income (expense)	453	426	1,520	620
Net loss	$ (6,090)	$ (5,906)	$ (20,570)	$ (13,070)
Net loss per share, basic and diluted	$ (0.24)	$ (0.24)	$ (0.83)	$ (1.16)
Weighted average common shares outstanding, basic and diluted	24,893,036	24,847,512	24,875,589	11,230,401
Net loss	$ (6,090)	$ (5,906)	$ (20,570)	$ (13,070)
Other comprehensive gain (loss):
Unrealized gain (loss) on marketable securities	(11)	(7)	44	(7)
Comprehensive loss	$ (6,101)	$ (5,913)	$ (20,526)	$ (13,077)