Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Consolidated Statements of Operations [Abstract]
License fees	$ 1,002	$ 4	$ 129
Grant revenue	0	0	1,044
Other expanded access program income, net	3,415	6,917	9,200
Total revenues	4,417	6,921	10,373
Operating expenses:
Research and development	27,917	4,757	9,207
General and administrative	12,229	10,256	9,840
Impairment Loss	25,990	0	0
Total operating expenses	66,136	15,013	19,047
Operating loss	(61,719)	(8,092)	(8,674)
Investment income	2,064	1,845	808
Interest expense	(10)	(109)	(781)
Gain on sale of asset, net	1	0	127,474
(Loss) income before income taxes	(59,664)	(6,356)	118,827
Income tax expense	0	78	477
Net (loss) income	(59,664)	(6,434)	118,350
Less: accretion of beneficial conversion charge	(9,175)	0	0
Net (loss) income attributable to common stockholders	$ (68,839)	$ (6,434)	$ 118,350
Basic net (loss) income attributable to common stockholders per common share (in dollars per share)	$ (2.95)	$ (0.49)	$ 9.31
Weighted average basic common shares outstanding (in shares)	23,348	13,250	12,712
Diluted net (loss) income attributable to common stockholders per common share (in dollars per share)	$ (2.95)	$ (0.49)	$ 9.30
Weighted average diluted common shares outstanding (in shares)	23,348	13,250	12,727