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	$ 1,788	$ 16,553	$ 6,629	$ 25,405
General and administrative	3,864	2,616	6,403	5,455
Total operating expenses	5,652	19,169	13,032	30,860
Loss from operations	(5,652)	(19,169)	(13,032)	(30,860)
Other income, net	54	847	403	1,478
Loss before income taxes	(5,598)	(18,322)	(12,629)	(29,382)
Income tax expense	1	10	8	19
Net loss	$ (5,599)	$ (18,332)	$ (12,637)	$ (29,401)
Net loss per share, basic and diluted	$ (0.15)	$ (0.51)	$ (0.35)	$ (0.91)
Weighted-average common shares used in computing net loss per share, basic and diluted	36,446,235	35,684,368	36,445,460	32,248,646
Other comprehensive gain (loss):
Net loss	$ (5,599)	$ (18,332)	$ (12,637)	$ (29,401)
Net unrealized (losses) gains on marketable securities	(32)	138	(49)	211
Comprehensive loss	$ (5,631)	$ (18,194)	$ (12,686)	$ (29,190)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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