CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues
Product revenues, net	$ 3,560		$ 5,732
Costs and expenses
Cost of product revenues	577		948
Research and development	2,179	$ 4,301	4,309	$ 8,363
Selling, general and administrative	22,062	20,173	44,909	31,698
Total costs and expenses	24,818	24,474	50,166	40,061
Loss from operations	(21,258)	(24,474)	(44,434)	(40,061)
Other expense (income):
Interest income (expense), net	137	(46)	235	(111)
Net loss	$ (21,121)	$ (24,520)	$ (44,199)	$ (40,172)
Loss per share - basic and diluted	$ (0.72)	$ (1.05)	$ (1.50)	$ (1.73)
Weighted-average shares - basic and diluted	29,441,514	23,417,378	29,396,143	23,273,765

Total costs related to goods produced and sold during the reporting period.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The net result for the period of deducting operating expenses from operating revenues.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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