Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Royalty revenue	$ 11	$ 97
Contract revenue	2,177	471
Total revenue	2,188	568
Cost of product revenue	238	213
Cost of contract revenue	1,635	403
Total cost of revenue	1,873	616
Gross profit	315	(48)
Research and development expense	4,828	3,318
Sales, marketing, general and administrative expense	2,607	2,580
Total operating expenses	7,435	5,898
Loss from operations	(7,120)	(5,946)
Other expenses, net	(12)	(3)
Net loss	$ (7,132)	$ (5,949)
Net loss per share - basic and diluted	$ (0.09)	$ (0.09)
Weighted-average shares outstanding - basic and diluted	78,610	68,113

Costs incurred and are directly related to generating contract revenues.

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Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

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