Condensed Consolidated Statements of Operations and Comprehensive Loss (unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Operating expenses:
Research and development	$ 11,845	$ 3,420	$ 19,951	$ 6,714
General and administrative	2,268	637	4,362	700
Total operating expenses	14,113	4,057	24,313	7,414
Loss from operations	(14,113)	(4,057)	(24,313)	(7,414)
Other income, net	522		863
Loss before income taxes	(13,591)	(4,057)	(23,450)	(7,414)
Net loss	$ (13,591)	$ (4,057)	$ (23,450)	$ (7,414)
Net loss per share, basic and diluted	$ (0.48)	$ (0.94)	$ (0.95)	$ (2.09)
Weighted-average common shares used in computing net loss per share, basic and diluted	28,046,315	4,302,231	24,802,713	3,550,198
Other comprehensive loss:
Net loss	$ (13,591)	$ (4,057)	$ (23,450)	$ (7,414)
Unrealized losses on marketable securities, net of income tax expense	(30)		(30)
Comprehensive loss	$ (13,621)	$ (4,057)	$ (23,480)	$ (7,414)

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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