Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenues:
Contract and grant revenue	$ 1,311	$ 1,682	$ 3,617	$ 4,267
License and royalty revenue	232	493	956	10,933
Total revenues	1,543	2,175	4,573	15,200
Operating expenses:
Research and development	4,500	3,682	12,080	13,901
Manufacturing and production	3,900	3,853	11,504	9,258
General and administrative	3,123	2,420	10,119	7,898
Total operating expenses	11,523	9,955	33,703	31,057
Loss from operations	(9,980)	(7,780)	(29,130)	(15,857)
Other income (expense):
Investment and other income, net	97	54	84	507
Net loss	$ (9,883)	$ (7,726)	$ (29,046)	$ (15,350)
Basic and diluted net loss per share	$ (0.11)	$ (0.09)	$ (0.33)	$ (0.18)
Weighted average shares used in computing basic and diluted net loss per share	86,998	86,408	86,755	85,762