STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Operating expenses:
Research and development	$ 13,570	$ 12,051	$ 26,906	$ 24,757
General and administrative	9,069	6,555	17,296	12,509
Total operating expenses	22,639	18,606	44,202	37,266
Operating Income (Loss), Total	(22,639)	(18,606)	(44,202)	(37,266)
Other income (expense), net	(31)	10	(22)	377
Net loss	$ (22,670)	$ (18,596)	$ (44,224)	$ (36,889)
Basic and diluted net loss per share	$ (0.11)	$ (0.09)	$ (0.21)	$ (0.18)
Weighted average common shares outstanding used to compute basic and diluted net loss per share	214,426,406	212,792,403	214,191,839	206,303,586