Unaudited Consolidated Statements of Operations - 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	$ 12,907	$ 8,833	$ 24,862	$ 16,722
General and administrative	3,809	3,307	8,080	6,193
Total operating expenses	16,716	12,140	32,942	22,915
Loss from operations	(16,716)	(12,140)	(32,942)	(22,915)
Interest income, net	499	1,077	1,246	1,949
Loss before income taxes	(16,217)	(11,063)	(31,696)	(20,966)
Income taxes	28		55
Net loss	(16,245)	(11,063)	(31,751)	(20,966)
Accretion of redeemable convertible preferred stock to redemption value				(49,900)
Net loss attributable to common stockholders	$ (16,245)	$ (11,063)	$ (31,751)	$ (70,866)
Per share information
Net loss per share of common stock, basic and diluted	$ (0.67)	$ (0.46)	$ (1.32)	$ (3.91)
Weighted average shares outstanding, basic and diluted	24,075,984	23,818,003	24,043,913	18,105,142