CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenues:
Royalty income	$ 1,176	$ 1,619	$ 2,333	$ 3,453
Collaboration revenue	514	94	1,367	385
Research grants	77	88	275	174
Other revenues	34	19	52	34
Total revenues	1,801	1,820	4,027	4,046
Expenses:
Research and development	10,068	7,957	18,789	18,866
License fees - research and development	153	110	223	150
Royalty expense	119	162	235	347
General and administrative	3,416	4,025	7,730	7,746
Depreciation and amortization	318	300	595	772
Total expenses	14,074	12,554	27,572	27,881
Operating loss	(12,273)	(10,734)	(23,545)	(23,835)
Other income:
Interest income	10	14	24	29
Total other income	10	14	24	29
Net loss	$ (12,263)	$ (10,720)	$ (23,521)	$ (23,806)
Net loss per share - basic and diluted	$ (0.24)	$ (0.32)	$ (0.46)	$ (0.70)
Weighted-average shares - basic and diluted	51,481	33,798	50,802	33,779