CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
REVENUE:
Product Development and Licensing Agreements	$ 838	$ 160	$ 146
Contracts and Grants	2,748	1,617	281
Product Royalties		2,334	10,775
Total Revenue	3,586	4,111	11,202
OPERATING EXPENSE:
Research and Development	104,381	67,401	47,398
Royalty		2,334	10,775
General and Administrative	20,622	14,805	10,016
Amortization of Acquired Intangible Assets	1,013	1,013	1,090
Total Operating Expense	126,016	85,553	69,279
Operating Loss	(122,430)	(81,442)	(58,077)
Investment and Other Income, Net	4,350	819	530
Interest Expense		(927)	(1,576)
Net Loss	(118,080)	(81,550)	(59,123)
Basic and Diluted Net Loss Per Common Share (in dollars per share)	$ (1.32)	$ (1.02)	$ (1.02)
Shares Used in Calculating Basic and Diluted Net Loss per Share (in shares)	89,399	79,777	57,713
COMPREHENSIVE LOSS:
Net Loss	(118,080)	(81,550)	(59,123)
Other Comprehensive Income (Loss):
Foreign Currency Translation Adjustments	(5)	(3)	2
Unrealized (Loss) Gain on Marketable Securities	(73)	(74)	91
Comprehensive Loss	$ (118,158)	$ (81,627)	$ (59,030)