CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenue	$ 214	$ 196	$ 359	$ 1,431
Operating expenses:
Research and development	11,772	9,420	36,196	26,111
Selling, general and administrative	5,574	4,210	14,196	11,934
Total operating expenses	17,346	13,630	50,392	38,045
Loss from operations	(17,132)	(13,434)	(50,033)	(36,614)
Investment income	3	2	10	10
Interest expense	(944)	(592)	(2,555)	(1,768)
Other income (expense), net	(254)	154	(382)	421
Net loss	(18,327)	(13,870)	(52,960)	(37,951)
Comprehensive loss	$ (18,327)	$ (13,870)	$ (52,960)	$ (37,951)
Basic and diluted net loss per share (USD per share)	$ (0.54)	$ (0.46)	$ (1.61)	$ (1.36)
Weighted-average shares used to compute basic and diluted net loss per share (shares)	34,005,642	29,844,507	32,945,346	27,984,133

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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