CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Costs and Expenses:
Research and development	$ 20,424	$ 20,946	$ 58,147	$ 58,724
Selling, General and administrative	2,728	2,506	14,727	7,963
Loss from Operations	(23,152)	(23,452)	(72,874)	(66,687)
Other Income/(Loss)
Interest and investment income/(expense), net (includes interest expense of $2,747 and $9,885 on Senior Convertible Debentures and $1,544 and $4,060 in amortization of deferred financing costs for the three and nine months ended September 30, 2015)	(4,291)	19	(13,815)	47
State R&D tax credits				83
Change in fair value of derivative instruments-warrants	1,446	425	(364)	1,404
Total Other Income/(Loss)	(2,845)	444	(14,179)	1,534
Net Loss	$ (25,997)	$ (23,008)	$ (87,053)	$ (65,153)
Net Loss per Common Share, Basic and Diluted
Net Loss per Common Share, Basic and Diluted (in dollars per share)	$ (0.23)	$ (0.24)	$ (0.85)	$ (0.70)
Weighted Average Common Shares Outstanding
Basic and Diluted (in shares)	111,328,339	94,738,048	102,838,814	93,631,115