Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Operating expenses
Research and development	$ 3,438	$ 28,618	$ 7,038	$ 50,622
General and administrative	6,003	7,572	10,920	15,228
Total operating expenses	9,441	36,190	17,958	65,850
Loss from operations	(9,441)	(36,190)	(17,958)	(65,850)
Interest income	249	242	442	441
Other income (expense), net	(656)	(521)	(1,313)	(782)
Net loss before provision for income taxes	(9,848)	(36,469)	(18,829)	(66,191)
Provision for income taxes		128		128
Net loss	$ (9,848)	$ (36,597)	$ (18,829)	$ (66,319)
Net loss per share - basic and diluted	$ (0.27)	$ (1.04)	$ (0.52)	$ (1.89)
Weighted-average common shares used to compute basic and diluted net loss per share	36,134	35,316	36,010	35,001

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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