Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Product revenue, net	$ 15,558us-gaap_SalesRevenueGoodsNet	$ 10,967us-gaap_SalesRevenueGoodsNet
Licensing revenue	375us-gaap_LicensesRevenue
Total revenue, net	15,933us-gaap_SalesRevenueNet	10,967us-gaap_SalesRevenueNet
Less: Cost of goods sold	5,627us-gaap_CostOfGoodsSold	4,246us-gaap_CostOfGoodsSold
Gross margin	10,306us-gaap_GrossProfit	6,721us-gaap_GrossProfit
Operating expenses:
Selling, general and administrative	24,741	20,585
Research and development	12,614us-gaap_ResearchAndDevelopmentExpense	11,707us-gaap_ResearchAndDevelopmentExpense
Total operating expenses	37,355us-gaap_OperatingExpenses	32,292us-gaap_OperatingExpenses
Operating loss	(27,049)us-gaap_OperatingIncomeLoss	(25,571)us-gaap_OperatingIncomeLoss
Gain on change in fair value of derivative liabilities	464us-gaap_UnrealizedGainLossOnDerivatives	4,393us-gaap_UnrealizedGainLossOnDerivatives
Interest expense, net	(4,885)	(4,393)
Other (expense) income, net	(128)us-gaap_OtherNonoperatingIncomeExpense	16us-gaap_OtherNonoperatingIncomeExpense
Loss from operations before taxes	(31,598)	(25,555)
Benefit from (provision for) income taxes	472us-gaap_IncomeTaxExpenseBenefit	(425)us-gaap_IncomeTaxExpenseBenefit
Net loss	(31,126)us-gaap_NetIncomeLoss	(25,980)us-gaap_NetIncomeLoss
Preferred stock purchase option	(868)
Net loss applicable to common shareholders	$ (31,994)	$ (25,980)
Loss per share:
Basic	$ (0.18)us-gaap_EarningsPerShareBasic	$ (0.15)us-gaap_EarningsPerShareBasic
Diluted	$ (0.18)us-gaap_EarningsPerShareDiluted	$ (0.15)us-gaap_EarningsPerShareDiluted
Weighted average shares:
Basic	175,582	172,872
Diluted	175,582	174,431

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