Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Product revenue	$ 0	$ 2,253	$ 0	$ 2,298
License and royalty revenue	10,000	77	10,011	280
Contract revenue	1,572	3,095	5,763	4,754
Total revenue	11,572	5,425	15,774	7,332
Cost of product revenue	1,434	3,178	1,998	3,572
Cost of contract revenue	1,211	2,525	4,201	3,740
Total cost of revenue	2,645	5,703	6,199	7,312
Gross profit	8,927	(278)	9,575	20
Research and development expense	6,386	3,427	17,905	10,417
Sales, marketing, general and administrative expense	2,253	2,062	6,953	6,967
Total operating expenses	8,639	5,489	24,858	17,384
Income (loss) from operations	288	(5,767)	(15,283)	(17,364)
Other income (expense), net	1	5	(19)	(3)
Net income (loss)	$ 289	$ (5,762)	$ (15,302)	$ (17,367)
Net income (loss) per share - basic	$ 0.00	$ (0.08)	$ (0.18)	$ (0.25)
Net income (loss) per share - diluted	$ 0.00	$ (0.08)	$ (0.18)	$ (0.25)
Weighted-average shares outstanding - basic	93,073	74,922	84,388	70,828
Weighted-average shares outstanding - diluted	93,204	74,922	84,388	70,828

Costs incurred and are directly related to generating contract revenues.

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