CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended			98 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Costs and Expenses:
Research and development	$ 50,630	$ 29,294	$ 13,419	$ 108,337
Purchased in-process research and development		1,000		29,157
General and administrative	11,681	7,941	6,745	39,266
Loss from Operations	(62,311)	(38,235)	(20,164)	(176,760)
Other Income /(Loss)
Interest and investment income	59	218	90	555
Interest expense	(21)		(12)	(33)
Other income		506	362	1,363
Change in fair value of derivative instruments-warrants	149	(1,933)	5,257	3,770
Total Other Income/(loss)	187	(1,209)	5,697	5,655
Loss from Continuing Operations	(62,124)	(39,444)	(14,467)	(171,105)
Loss from discontinued operations				(72)
Net loss	$ (62,124)	$ (39,444)	$ (14,467)	$ (171,177)
Weighted Average Common Shares Outstanding
Basic and Diluted (in shares)	85,220,458	61,702,277	47,598,240
Net Loss per Common Share, Basic and Diluted
Net Loss per Common Share, Basic and Diluted (in dollars per share)	$ (0.73)	$ (0.64)	$ (0.30)