Condensed Consolidated Statements of Operations and Comprehensive Loss (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating expenses:
Research and development	$ 2,103	$ 3,416	$ 5,067	$ 6,180
General and administrative	2,442	865	3,726	1,725
Total operating expenses	4,545	4,281	8,793	7,905
Loss from operations	(4,545)	(4,281)	(8,793)	(7,905)
Other income:
Interest income	5	80	21	115
Total other income	5	80	21	115
Net loss	(4,540)	(4,201)	(8,772)	(7,790)
Comprehensive loss	$ (4,540)	$ (4,201)	$ (8,772)	$ (7,790)
Net loss per share attributable to common stockholders—basic and diluted	$ (0.56)	$ (23.04)	$ (2.11)	$ (44.64)
Weighted-average common shares outstanding—basic and diluted	8,182,725	185,683	4,206,793	177,962