Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2014

Stockholders' Equity

Summary of stock option activity

(in thousands)	Options		Weighted Average Exercise Price
Outstanding at December 31, 2013	1,820,784		$	4.46
Granted	876,500		5.37
Exercised	(50,304	)	1.18
Cancelled	(98,666	)	6.35
Outstanding at March 31, 2014	2,548,314		$	4.77
Weighted-average fair value of options granted during the period			$	3.45

Schedule of recorded stock-based compensation expense in the condensed consolidated statements of comprehensive loss

	Three Months
	Ended March 31,
(in thousands)	2014		2013
General and administrative	$	226	$	85
Research and development	265		96
	$	491	$	181