Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Operating expenses:
Research and development	$ 48,668	$ 28,460
General and administrative	19,223	13,992
Total operating expenses	67,891	42,452
Loss from operations	(67,891)	(42,452)
Interest and other income, net	1,634	1,009
Net loss	(66,257)	(41,443)
Unrealized gain (loss) on available-for-sale securities	378	(373)
Comprehensive loss	$ (65,879)	$ (41,816)
Net loss per common share:
Basic and diluted net loss per common share	$ (1.44)	$ (1.05)
Weighted-average shares outstanding used to calculate basic and diluted net loss per common share	46,124	39,596

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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