Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	3 Months Ended		248 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011
Cash flows from operating activities:
Net loss	$ (14,538)	$ (7,523)	$ (427,663)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	98	65	15,909
Amortization of premium/discount on marketable securities, net	63	236	1,332
Amortization of debt discount			570
Gain on sale of marketable securities			43
Purchased in-process research and development			4,500
Share-based compensation expense	2,164	2,172	28,988
Common stock issued in exchange for services provided			15
Loss on property and equipment	12		387
Changes in assets and liabilities:
Accounts receivable	17	156	(37)
Prepaid expenses and other assets	(677)	26	(2,945)
Accounts payable	1,862	173	6,987
Accrued liabilities	(240)	(66)	1,344
Deferred revenue		(1,933)	7,000
Deferred rent	70	(7)	480
Net cash used in operating activities	(11,169)	(6,701)	(363,090)
Cash flows from investing activities:
Purchase of property and equipment	(384)	(110)	(14,124)
(Payments for) proceeds from disposal or sale of property and equipment	(12)		111
Purchase of marketable securities		(39,258)	(649,074)
Proceeds from sales of marketable securities			114,839
Proceeds from maturities of marketable securities	6,190	8,230	514,520
Net cash provided by (used in) investing activities	5,794	(31,138)	(33,728)
Cash flows from financing activities:
Issuance of common stock, net of issuance costs	(571)	3	435,621
Exercise of stock options and stock purchase rights	5,114	659	22,403
Proceeds from related party notes payable			6,400
Proceeds from note payable			3,000
Issuance of convertible preferred stock, net of issuance costs			20,514
Payments under capital lease obligations			(3,881)
Repayment of notes payable			(314)
Net cash provided by financing activities	4,543	662	483,743
(Decrease)/Increase in cash and cash equivalents	(832)	(37,177)	86,925
Cash and cash equivalents at beginning of period	87,757	51,199
Cash and cash equivalents at end of period	86,925	14,022	86,925
Supplemental disclosure of non-cash investing and financing activities:
Accounts payable for property and equipment purchases	190		190
Accrued stock issuance costs			559
Receivable for stock option exercises			389
Settlement of related party notes payable by issuance of common stock			6,086
Property and equipment acquired under capital lease obligations			3,881
Warrants issued			49
Conversion of notes payable and accrued interest into convertible preferred stock			$ 3,051