CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS
Revenue
Operating expenses:
Research and development	36,186	$ 20,871
General and administrative	12,664	13,535
Total operating expenses	48,850	34,406
Loss from operations	(48,850)	(34,406)
Other income (expense):
Interest income	1,049	2,308
Interest expense	(985)	(583)
Other income (expense), net	300	100
Total other income (expense), net	364	1,825
Net loss	$ (48,486)	$ (32,581)
Net loss per share, basic and diluted	$ (0.60)	$ (0.42)
Weighted average common shares outstanding, basic and diluted	80,271,848	77,544,089
Comprehensive loss:
Net loss	$ (48,486)	$ (32,581)
Other comprehensive income (loss):
Unrealized gains (losses) on investments, net of tax of $0	456	110
Comprehensive loss	$ (48,030)	$ (32,471)