Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue:
Total revenue				$ 22,254
Type of Revenue [Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Operating expenses:
Research and development	$ 17,221	$ 16,420	$ 58,388	$ 49,218
General and administrative	3,906	3,087	12,054	10,093
Total operating expenses	21,127	19,507	70,442	59,311
Loss from operations	(21,127)	(19,507)	(70,442)	(37,057)
Interest and other income, net	834	658	2,310	1,927
Net loss	$ (20,293)	$ (18,849)	$ (68,132)	$ (35,130)
Net loss per share, basic and diluted	$ (0.38)	$ (0.52)	$ (1.52)	$ (0.98)
Weighted average common shares used to compute net loss per share, basic and diluted	53,775	36,405	44,703	36,021

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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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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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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