STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Revenue	$ 5,008	$ 175	$ 8,843	$ 292
Operating expenses:
Research and development	6,239	7,870	17,237	23,226
General and administrative	2,737	2,844	8,926	8,528
Total operating expenses	8,976	10,714	26,163	31,754
Loss from operations	(3,968)	(10,539)	(17,320)	(31,462)
Other income (expense):
Interest income	22	50	106	138
Interest expense	(2)	(2)	(6)	(6)
Change in fair value of warrant liability	736	133	1,973	1,771
Loss from operations before income tax	(3,212)	(10,358)	(15,247)	(29,559)
Income tax (benefit) expense	0	(136)	412	(136)
Net loss	$ (3,212)	$ (10,222)	$ (15,659)	$ (29,423)
Basic and diluted net loss per share	$ (0.03)	$ (0.10)	$ (0.14)	$ (0.29)
Basic and diluted weighted average number of common shares outstanding	115,107	107,092	113,053	102,683