Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Operating expenses:
General and administrative	$ 13,154	$ 5,418	$ 22,803	$ 10,242
Research and development	45,206	10,380	65,521	26,445
Total operating expenses	58,360	15,798	88,324	36,687
Loss from operations	(58,360)	(15,798)	(88,324)	(36,687)
Interest income (expense)	331	79	576	132
Net loss	(58,029)	(15,719)	(87,748)	(36,555)
Comprehensive loss	$ (58,029)	$ (15,719)	$ (87,748)	$ (36,555)
Basic and diluted net loss per common share (in dollars per share)	$ (2.07)	$ (0.68)	$ (3.15)	$ (1.84)
Weighted-average basic and diluted common shares outstanding (in shares)	27,971,733	23,013,838	27,850,199	19,876,850

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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