Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Operating expenses:
Research and development	$ 14,751	$ 10,131
General and administrative	9,040	5,576
Total operating expenses	23,791	15,707
Operating loss	(23,791)	(15,707)
Other income, net	885	1,218
Net loss	(22,906)	(14,489)
Other comprehensive loss:
Net unrealized (loss) gain on marketable securities	(54)	3
Foreign currency translation adjustment	(54)	42
Comprehensive loss	$ (23,014)	$ (14,444)
Net loss per share — basic and diluted (in USD per share)	$ (0.31)	$ (0.23)
Weighted-average common shares used to compute net loss per share - basic and diluted (in shares)	73,797	63,125

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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