CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Expenses
Research and development	$ 14,397	$ 17,988
General and administrative	3,693	4,130
Total operating expenses	18,090	22,118
Loss from operations	(18,090)	(22,118)
Other income, net	244	204
Net loss	(17,846)	(21,914)
Unrealized gain on available-for-sale investments	71	27
Comprehensive loss	$ (17,775)	$ (21,887)
Basic and diluted net loss per share	$ (0.73)	$ (1.13)
Weighted average number of shares used in computing net loss per share, basic and diluted	24,383,941	19,380,840

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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