Condensed Consolidated Statements of Expenses (Unaudited) (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended		103 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011
Expenses:
Research and development expense	$ 2,506	$ 1,484	$ 4,451	$ 2,983	$ 31,130
Research and development employee stock based compensation expense	212	267	458	540	2,865
Research and development non-employee stock based compensation expense	(45)	513	(76)	667	5,987
Fair value of common stock issued in exchange for licensing rights					3,954
Total research and development expenses	2,673	2,264	4,833	4,190	43,936
General and administrative	1,610	1,654	3,531	3,102	24,641
General and administrative employee stock based compensation	328	646	1,427	1,418	8,812
Common stock warrants issued for general and administrative expenses	11	190	87	500	2,381
Fair value of common stock issued in exchange for general and administrative expenses			23		304
Total general and administrative expenses	1,949	2,490	5,068	5,020	36,138
Operating loss	(4,622)	(4,754)	(9,901)	(9,210)	(80,074)
Interest income (expense)	(3)	3	(4)	2	624
Other income (Note 7)	3,243	2,610	4,678	3,181	8,443
Net loss	$ (1,382)	$ (2,141)	$ (5,227)	$ (6,027)	$ (71,007)
Net loss per common share:
Basic and diluted loss per share	$ (0.04)	$ (0.12)	$ (0.18)	$ (0.35)
Weighted average common shares outstanding:
Basic and diluted	38,568,501	18,371,808	29,492,756	17,384,606