Unaudited Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue
Net product sales	$ 1,593	$ 0	$ 2,402	$ 0
Total revenue	1,593	0	2,402	0
Operating expenses
Cost of product sales	129	0	187	0
Research and development	30,867	20,808	59,296	38,573
Selling, general and administrative	22,164	6,022	45,180	11,525
Total operating expenses	53,160	26,830	104,663	50,098
Loss from operations	(51,567)	(26,830)	(102,261)	(50,098)
Interest (expense) income, net	(1,211)	101	(1,045)	129
Net loss	$ (52,778)	$ (26,729)	$ (103,306)	$ (49,969)
Net loss per share, basic and diluted (usd per share)	$ (2.02)	$ (1.21)	$ (4.22)	$ (2.46)
Weighted-average common shares outstanding - basic and diluted (in shares)	26,182	22,123	24,462	20,277

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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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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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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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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