CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Revenue
Total revenue	$ 1,244	$ 9,467
Operating expenses
Research and development	34,240	19,659
General and administrative	9,762	5,154
Total operating expenses	44,002	24,813
Loss from operations	(42,758)	(15,346)
Other income, net	1,846	637
Net loss	(40,912)	(14,709)
Unrealized gain (loss) on available-for-sale investments	158	(288)
Comprehensive loss	$ (40,754)	$ (14,997)
Basic and diluted net loss per share (USD per share)	$ (1.17)	$ (0.51)
Weighted average number of shares used in computing net loss per share, basic and diluted (shares)	34,980,361	28,843,578

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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