Quarterly Financial Data (unaudited) (Tables)

12 Months Ended

Dec. 31, 2014

Quarterly Financial Data (unaudited)

Schedule of quarterly results of operations

	Three Months Ended
	March 31, 2014			June 30, 2014			September 30, 2014			December 31, 2014
	(in thousands, except shares and per share data)
Revenues:
Total revenues	$	—		$	—		$	—		$	—
Operating expenses:
Research and development		17,583			18,761			16,208			15,653
General and administrative		5,324			2,940			3,241			4,241
Total operating expenses		22,907			21,701			19,449			19,894
Loss from operations		(22,907	)		(21,701	)		(19,449	)		(19,894	)
Interest expense, net		(650	)		(585	)		(517	)		(458	)
Net loss	$	(23,557	)	$	(22,286	)	$	(19,966	)	$	(20,352	)
Basic and diluted net loss per common share	$	(0.28	)	$	(0.24	)	$	(0.19	)	$	(0.19	)
Basic and diluted weighted average number of common shares outstanding		85,438,127			94,046,278			105,774,949			108,366,504

	Three Months Ended
	March 31, 2013			June 30, 2013			September 30, 2013			December 31, 2013
	(in thousands, except shares and per share data)
Revenues:
Total revenues	$	—		$	—		$	—		$	—
Operating expenses:
Research and development		16,380			17,876			17,623			19,981
General and administrative		3,878			4,187			4,171			3,463
Total operating expenses		20,258			22,063			21,794			23,444
Loss from operations		(20,258	)		(22,063	)		(21,794	)		(23,444	)
Interest expense, net		(470	)		(724	)		(721	)		(718	)
Net loss	$	(20,728	)	$	(22,787	)	$	(22,515	)	$	(24,162	)
Basic and diluted net loss per common share	$	(0.30	)	$	(0.33	)	$	(0.33	)	$	(0.31	)
Basic and diluted weighted average number of common shares outstanding		68,991,371			69,034,823			69,047,161			76,769,199