CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 112,235	$ 44,778
Short-term investments	161,209	196,137
Receivable from related party	71	223
Note receivable, current	100	100
Prepaid and other current assets	3,772	3,525
Inventory	5,148
Total current assets	282,535	244,763
Long-term marketable securities	88,962
Restricted cash	833	893
Property and equipment, net	9,579	10,372
Notes receivable, non-current	140	240
Other assets, non-current	1,894	2,514
Total assets	383,943	258,782
Current liabilities:
Accounts payable	4,757	5,813
Accrued personnel-related expenses	7,714	9,643
Accrued clinical and development expenses	6,761	6,956
Accrued interest on convertible subordinated notes	1,078	2,372
Other accrued liabilities	1,835	1,946
Note payable and capital lease		69
Deferred revenue, current	4,945	18,697
Total current liabilities	27,090	45,496
Convertible subordinated notes	172,500	172,500
Deferred rent	5,275	5,821
Deferred revenue, non-current	5,790	122,017
Commitments and contingencies (Notes 3 and 7)
Stockholders' equity (net capital deficiency):
Common stock, $0.01 par value; authorized: 200,000 shares; outstanding: 97,854 at September 30, 2012 and 85,543 at December 31, 2011	979	855
Additional paid-in capital	1,475,371	1,228,037
Accumulated other comprehensive income	116	16
Accumulated deficit	(1,303,178)	(1,315,960)
Total stockholders' equity (net capital deficiency)	173,288	(87,052)
Total liabilities and stockholders' equity (net capital deficiency)	$ 383,943	$ 258,782