STOCK-BASED COMPENSATION (Tables)

9 Months Ended

Sep. 30, 2016

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

The following table summarizes the Company’s stock awards granted for each of the periods indicated:

	For the Three Months Ended September 30,									For the Nine Months Ended September 30,
	2016					2015				2016					2015
	Grants			Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value		Grants			Weighted Average Grant Date Fair Value		Grants		Weighted Average Grant Date Fair Value
Stock options		1,050		$	37.38		702,067	$	24.05		1,214,426	⁽¹⁾	$	11.96		2,676,778	$	14.67
Restricted stock awards		91,778	⁽²⁾	$	48.94		65,000	$	33.81		117,553	⁽³⁾	$	41.22		181,783	$	20.80

(1)

Included in 2016 stock option grants are 287,500 options with performance conditions. As a result of the approval of EXONDYS 51, 25% of these performance grants vested immediately and another 25% were triggered to be eligible for vesting subject to the remaining service conditions of the awards. As of September 30, 2016, the performance conditions of the remaining 50% were not probable of being achieved. The remaining stock options granted during the periods presented in the table have only service-based criteria and vest over four years.

(2)

The Company granted certain employees 91,778 restricted stock awards (“RSA”) with certain sales targets. If and when deemed probable that such performance milestones may be achieved within the required time frame, the Company may recognize up to $4.5 million of stock-based compensation related to these grants.

(3)

Included in the 2016 RSA grants are 18,755 shares granted to certain employees in lieu of a portion of their 2015 annual bonus payments. These RSA grants were fully vested as of September 30, 2016. The remaining RSAs will be fully vested by June 2017.

Summary of Stock-Based Compensation Expense by Function Included within Condensed Consolidated Statement of Operations and Comprehensive Loss

The following table summarizes stock-based compensation expense by function included within the unaudited condensed consolidated statements of operations and comprehensive loss:

	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2016		2015		2016		2015
	(in thousands)
Research and development	$	2,674	$	2,631	$	7,527	$	7,639
General and administrative		6,899		3,052		15,566		18,130
Total stock-based compensation expense	$	9,573	$	5,683	$	23,093	$	25,769

Summary of Stock-Based Compensation Expense by Grant Type Included within Condensed Consolidated Statement of Operations and Comprehensive Loss

The following table summarizes stock-based compensation expense by grant type included within the unaudited condensed consolidated statements of operations and comprehensive loss:

	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2016		2015		2016		2015
	(in thousands)
Stock options	$	8,778	$	4,801	$	20,248	$	23,451
Restricted stock awards		232		136		689		310
Stock appreciation rights		115		115		345		377
Employee stock purchase plan		448		631		1,811		1,631
Total stock-based compensation expense	$	9,573	$	5,683	$	23,093	$	25,769