CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating expenses:
Research and development	$ 22,504	$ 22,761
Selling, general, and administrative	12,796	7,759
Total operating expenses	35,300	30,520
Loss from operations	(35,300)	(30,520)
Other income (expense):
Interest income, net	1,136	1,546
Total other income, net	1,136	1,546
Net loss	(34,164)	(28,974)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ (34,164)	$ (28,974)
Net loss per share attributable to common stockholders, basic and diluted	$ (0.78)	$ (0.84)
Weighted-average common shares outstanding, basic and diluted	44,049,843	34,417,189
Other comprehensive loss:
Net loss	$ (34,164)	$ (28,974)
Unrealized gain on marketable securities	63
Comprehensive loss	$ (34,101)	$ (28,974)