Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenues:
Product sales	$ 677us-gaap_SalesRevenueGoodsNet
Product royalty revenues	194us-gaap_RoyaltyRevenue	954us-gaap_RoyaltyRevenue
Research and development reimbursements	775	8,452
Contract revenue	11,408us-gaap_ContractsRevenue	11,284us-gaap_ContractsRevenue
Total revenues	13,054us-gaap_Revenues	20,690us-gaap_Revenues
Cost of sales	1,124us-gaap_CostOfRevenue	726us-gaap_CostOfRevenue
Expenses:
Research and development	6,549us-gaap_ResearchAndDevelopmentExpense	14,623us-gaap_ResearchAndDevelopmentExpense
Selling, general and administrative	13,181	4,628
Total expenses	19,730us-gaap_OperatingExpenses	19,251us-gaap_OperatingExpenses
(Loss) income from operations	(7,800)us-gaap_OperatingIncomeLoss	713us-gaap_OperatingIncomeLoss
Interest expense, net	(420)us-gaap_InterestIncomeExpenseNet	(555)us-gaap_InterestIncomeExpenseNet
Derivative loss		(4,825)
Other income, net	27us-gaap_OtherNonoperatingIncomeExpense	23us-gaap_OtherNonoperatingIncomeExpense
Net loss attributable to common stockholders	$ (8,193)	$ (4,644)
Basic earnings per share	$ (0.16)us-gaap_EarningsPerShareBasic	$ (0.11)us-gaap_EarningsPerShareBasic
Diluted earnings per share	$ (0.16)us-gaap_EarningsPerShareDiluted	$ (0.11)us-gaap_EarningsPerShareDiluted
Weighted average common stock shares outstanding	51,908,844	44,305,288

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