Selected Quarterly Data (Tables)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information Disclosure [Abstract]

Summarized Quarterly Information

Summarized quarterly data for 2015 and 2014 are as follows (in thousands, except per share data):

	For the Quarters Ended
	March 31			June 30			September 30			December 31			Total Year
2015:
Operating expenses	$	14,817		$	15,078		$	12,335		$	9,890		$	52,120
Net loss	(14,758		)	(15,106		)	(12,300		)	(9,859		)	(52,023		)
Net loss attributable to common stockholders	(14,758		)	(15,106		)	(12,300		)	(9,859		)	(52,023		)
Basic and diluted net loss per share attributable to common stockholders (1)	$	(0.62	)	$	(0.63	)	$	(0.51	)	$	(0.34	)
2014:
Operating expenses	$	11,876		$	11,638		$	12,810		$	14,018		$	50,342
Net loss	(10,748		)	(10,167		)	(12,798		)	(13,954		)	(47,667		)
Net loss attributable to common stockholders	(13,818		)	(16,251		)	(12,798		)	(13,954		)	(56,821		)
Basic and diluted net loss per share attributable to common stockholders (1)	$	(24.49	)	$	(0.91	)	$	(0.59	)	$	(0.59	)

(1) Net loss per share is computed independently for each of the quarters presented. Therefore, the sum of the quarterly per share calculations will not necessarily equal the annual per share calculation.