11. Stock-Based Compensation

The Company recognized stock-based compensation expense on all employee and non-employee awards as follows:


	For the three months				For the Nine months
	ended September 30,				ended September 30,
(in thousands)	2014		2013		2014		2013
Research and development	$	340	$	119	$	1,126	$	511
General and administrative		808		690		2,457		1,971

Stock-based employee compensation expense	$	1,148	$	809	$	3,583	$	2,482

The Company granted 10,000 and 114,300 stock options during the three and nine months ended September 30, 2014 that had a weighted-average grant date fair value of $2.29 and $3.15 per share, respectively. The Company granted 125,000 and 1,551,400 stock options during the three and nine months ended September 30, 2013 that had a weighted-average grant date fair value of $2.47 and $1.94 per share, respectively.

At September 30, 2014, total unrecognized compensation costs related to unvested stock options outstanding amounted to $4.8 million. The cost is expected to be recognized over a weighted-average period of 1.48 years.

On May 31, 2013, the Company extended the contractual life of 66,667 fully vested stock options held by one employee from 3 to 12 months.

On June 14, 2013, the Company extended the contractual life of 71,167 fully vested stock options held by one employee from 3 to 12 months.

On March 31, 2014, the Company extended the contractual life of 71,167 fully vested stock options held by one employee by an additional 9 months.

On March 31, 2014, the Company extended the contractual life of 33,333 fully vested stock options and 66,667 unvested stock options held by one employee.

On September 8, 2014, the Company extended the contractual life of 82.834 fully vested stock options and 23,333 unvested stock options held by one employee by an additional 3 months.

On September 15, 2014, the Company extended the contractual life of 39,167 fully vested stock options and 113,333 unvested stock options held by one employee.

For the three months ended September 30, 2014 and 2013, the fair value of stock options was estimated on the date of grant using a Black-Scholes option valuation model with the following assumptions:


	For the three months ended September 30,
	2014			2013
Risk-free interest rate		2.03	%	1.61 - 1.74%
Expected life in years		6		6
Expected volatility		92.36	%	94.96 - 95.64%
Expected dividend yield		0		0

Stock option activity under the Company’s stock option plan for the nine months ended September 30, 2014 is as follows:


(in thousands, except share and per share data)	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Contractual Term (Years)		Aggregate Intrinsic Value
Outstanding, December 31, 2013		6,747,302		$	3.81

Granted		114,300			4.11
Exercised		(585,638	)		2.26
Cancelled		(483,536	)		4.28


Outstanding, September 30, 2014		5,792,428		$	3.94		6.91	$	1,457


Vested and unvested expected to vest at June 30, 2014		5,731,490		$	4.12		5.41	$	1,441


Options exercisable, September 30, 2014		3,257,661		$	4.12		5.41	$	498


Options exercisable, December 31, 2013		3,471,935		$	4.01		5.03	$	2,654


Options available for future grant		5,555,864

A summary of the status of unvested restricted stock for the nine months ended September 30, 2014 is as follows:


	Number of Shares			Weighted-Average Grant Date Fair Value
Non-vested, December 31, 2013		352,865		$	4.38
Granted		—			—
Vested		(48,433	)		4.51
Cancelled		(20,999	)		4.41


Non-vested, September 30, 2014		283,433		$	4.35

At September 30, 2014, total unrecognized compensation costs related to unvested restricted stock outstanding amounted to $0.4 million. The cost is expected to be recognized over a weighted-average period of 1.08 years.