CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Expenses
Research and development	$ 18,441	$ 11,276	$ 36,429	$ 19,483
General and administrative	3,786	4,240	7,916	8,019
Total operating expenses	22,227	15,516	44,345	27,502
Loss from operations	(22,227)	(15,516)	(44,345)	(27,502)
Other income, net	166	70	370	116
Net loss	(22,061)	(15,446)	(43,975)	(27,386)
Unrealized gain (loss) on available-for-sale investments	33	(9)	60	(4)
Comprehensive loss	$ (22,028)	$ (15,455)	$ (43,915)	$ (27,390)
Basic and diluted net loss per share	$ (1.11)	$ (0.95)	$ (2.24)	$ (1.74)
Weighted average number of shares used in computing net loss per share, basic and diluted	19,912,938	16,235,261	19,646,889	15,727,891

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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