Condensed Consolidated Statements of Operations (Unaudited) (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
Revenues:
Collaboration revenue - related party	$ 1,982	$ 3,424	$ 5,715	$ 6,366
Other revenue	656	364	1,967	1,421
Total revenues	2,638	3,788	7,682	7,787
Operating expenses:
Cost of revenues	595	566	1,731	1,800
Research and development	10,190	11,637	28,530	35,548
General and administrative	3,900	4,440	12,293	14,308
Restructuring charges				2,238
Total operating expenses	14,685	16,643	42,554	53,894
Loss from operations	(12,047)	(12,855)	(34,872)	(46,107)
Other income (expense), net	338	(76)	1,019	712
Loss before income taxes	(11,709)	(12,931)	(33,853)	(45,395)
Income tax expense (benefit)		1	(1)	(3)
Net loss	$ (11,709)	$ (12,930)	$ (33,854)	$ (45,398)
Basic and diluted net loss per common share	$ (0.12)	$ (0.18)	$ (0.39)	$ (0.65)
Shares used in computing basic and diluted net loss per common share	96,133	72,934	87,414	69,941