CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues:
Royalty income	$ 5,923	$ 4,963	$ 3,046
Collaboration revenue	1,595	8,525	76,764
Research grants	275	488	4,810
Other revenues	69	72	176
Total revenues	7,862	14,048	84,796
Expenses:
Research and development	33,903	31,840	53,183
License fees - research and development	567	1,170	578
Royalty expense	624	499	405
General and administrative	14,809	14,706	18,248
Depreciation and amortization	939	1,324	2,066
Total expenses	50,842	49,539	74,480
Operating (loss) income	(42,980)	(35,491)	10,316
Other income:
Interest income	46	60	65
Total other income	46	60	65
Net (loss) income before provision for income taxes	(42,934)	(35,431)	10,381
Income tax benefit	362	0	0
Net (loss) income	$ (42,572)	$ (35,431)	$ 10,381
Net (loss) income per share - basic	$ (0.76)	$ (1.02)	$ 0.31
Weighted-average shares - basic	55,798	34,754	33,375
Net (loss) income per share - diluted	$ (0.76)	$ (1.02)	$ 0.31
Weighted-average shares - diluted	55,798	34,754	33,494