Condensed Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Condensed Statements of Operations
License fees	$ 1,036	$ 1,036
Operating expenses:
Research and development	7,526	8,999
General and administrative	2,648	2,145
Sales and marketing	1,759	594
Total operating expenses	11,933	11,738
Loss from operations	(10,897)	(10,702)
Investment income	62	62
Interest expense	(19)	(5)
Net loss	$ (10,854)	$ (10,645)
Net loss per share-basic and diluted (in dollars per share)	$ (0.17)	$ (0.19)
Weighted average common shares outstanding-basic and diluted (in shares)	63,836	56,718