Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2014

Activity Under Equity Incentive Plans Related to Stock Options

Activity under the Company’s equity incentive plans related to stock options is set forth below (in thousands except per share amounts):

	Number of Options   Outstanding		Weighted     Average Exercise Price per Share
Balance at December 31, 2013		10,405	$	3.46
Granted		2,734		5.93
Forfeited		(134)		4.77
Expired		(40)		8.61
Exercised		(967)		2.41
Balance at September 30, 2014		11,998	$	4.08

Recognition of Stock-Based Compensation Expense

Stock-based compensation recognized on the Company’s condensed consolidated statements of operations for the three and nine months ended September 30, 2014 and 2013, was as follows (in thousands):

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2014		2013		2014		2013
Stock-based compensation expense by caption:
Research and development	$	281	$	132	$	740	$	341
Selling, general and administrative		1,197		729		3,024		2,074
Total stock-based compensation expense	$	1,478	$	861	$	3,764	$	2,415