STOCK-BASED COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2018

STOCK-BASED COMPENSATION

Schedule of stock-based compensation expense

	Year Ended December 31,
(In thousands)	2018		2017		2016
Research and development	$	—	$	697	$	632
General and administrative		3,233		9,136		7,665
Total stock-based compensation expense	$	3,233	$	9,833	$	8,297

Schedule of stock-based compensation expense included in the consolidated statements of operations by award type

	Year Ended December 31,
(In thousands)	2018		2017		2016
Stock options	$	305	$	593	$	632
RSUs		1,650		2,282		1,920
RSAs		1,920		4,497		3,492
Performance-based RSAs		—		242		1,293
Market-based RSUs (PSUs)		(224)		291		112
Market-based RSAs (PSAs)		(464)		1,855		693
ESPP		46		73		155
Total stock-based compensation expense	$	3,233	$	9,833	$	8,297

Schedule of unrecognized stock-based compensation cost and the estimated weighted-average amortization period

As of December 31, 2018, the unrecognized stock-based compensation cost and the estimated weighted-average amortization period were as follows:

	Unrecognized		Weighted-Average
	Compensation		Amortization
(In thousands)	Cost		Period (Years)
RSUs	$	682	0.6
RSAs		761	2.2
Total unrecognized compensation cost	$	1,443

Summary of equity award activity under the 2012 plan and prior plans

		Weighted-
		Average			Weighted-			Weighted-
		Exercise			Average			Average
	Number of	Price of		Number of	Fair Value		Number of	Fair Value
	outstanding	Outstanding		outstanding	per Share		outstanding	per Share
(In thousands, except per share data)	options	Options		RSUs and PSUs	at Grant		RSAs and PSAs	at Grant
Balance as of December 31, 2017	1,655	$	23.89	370	$	11.57	1,448	$	10.61
Granted	—		—	177		14.29	202		13.11
Exercised	(84)		12.22	—		—	—		—
Released RSUs/RSAs	—		—	(224)		13.33	(444)		12.49
Forfeited	(334)		26.43	(218)		10.07	(1,129)		10.00
Balance as of December 31, 2018	1,237		24.00	105		15.54	77		15.37