Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Operating expenses
Research and development	$ 1,027	$ 42,673	$ 8,065	$ 93,295
General and administrative	5,191	7,073	16,111	22,301
Total operating expenses	6,218	49,746	24,176	115,596
Loss from operations	(6,218)	(49,746)	(24,176)	(115,596)
Interest income	261	220	703	661
Other income (expense), net	(593)	(262)	(1,906)	(1,044)
Net loss before provision for income taxes	(6,550)	(49,788)	(25,379)	(115,979)
Provision for income taxes				128
Net loss	$ (6,550)	$ (49,788)	$ (25,379)	$ (116,107)
Net loss per share - basic and diluted	$ (1.08)	$ (8.37)	$ (4.23)	$ (19.72)
Weighted-average common shares used to compute basic and diluted net loss per share	6,040	5,945	5,998	5,889

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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