CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				12 Months Ended
	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2010
Revenues:
Research and development support	$ 1,566	$ 2,190	$ 2,005	$ 1,495	$ 4,517	$ 7,256	$ 5,365
License and milestone fees	2,859	858	866	1,810	9,161	6,393	5,698
Clinical materials revenue	2,080	2,163	1,307	106	2,679	5,656	2,880
Total revenues	6,505	5,211	4,178	3,411	16,357	19,305	13,943
Operating Expenses:
Research and development	18,261	15,763	16,004	13,425	69,192	63,453	50,280
General and administrative	4,438	4,550	3,688	3,364	20,422	16,040	14,898
Total operating expenses	22,699	20,313	19,692	16,789	89,614	79,493	65,178
Loss from operations	(16,194)	(15,102)	(15,514)	(13,378)	(73,257)	(60,188)	(51,235)
Investment income, net					66	218	176
Other (expense) income, net	44	99	1,281	490	(128)	1,696	(118)
Loss before benefit for income taxes	(16,150)	(15,003)	(14,233)	(12,888)	(73,319)	(58,274)	(51,177)
Benefit for income taxes							(265)
Net loss	$ (16,150)	$ (15,003)	$ (14,233)	$ (12,888)	$ (73,319)	$ (58,274)	$ (50,912)
Basic and diluted net loss per common share (in dollars per share)	$ (0.23)	$ (0.22)	$ (0.21)	$ (0.19)	$ (0.95)	$ (0.85)	$ (0.87)
Basic and diluted weighted average common shares outstanding (in shares)					76,814	68,919	58,845