STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenue	$ 3,001	$ 7	$ 3,835	$ 117
Operating expenses:
Research and development	5,584	6,327	10,998	15,356
General and administrative	3,338	3,148	6,188	5,683
Total operating expenses	8,922	9,475	17,186	21,039
Loss from operations	(5,921)	(9,468)	(13,351)	(20,922)
Other income (expense):
Interest income	38	44	84	88
Interest expense	(2)	(2)	(4)	(4)
Change in fair value of warrant liability	1,304	569	1,237	1,638
Loss from operations before income tax	(4,581)	(8,857)	(12,034)	(19,200)
Income tax expense	412	0	412	0
Net loss	$ (4,993)	$ (8,857)	$ (12,446)	$ (19,200)
Basic and diluted net loss per share	$ (0.04)	$ (0.09)	$ (0.11)	$ (0.19)
Basic and diluted weighted average number of common shares outstanding	112,821	100,694	112,009	100,442