Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Product revenue	$ 0	$ 3,155
Royalty revenue	535	542
Contract revenue	257	4
Total revenue	792	3,701
Cost of product revenue	213	2,588
Cost of contract revenue	325	1
Total cost of revenue	538	2,589
Gross profit	254	1,112
Research and development expense	3,318	2,597
Sales, marketing, general and administrative expense	2,580	2,068
Total operating expenses	5,898	4,665
Loss from operations	(5,644)	(3,553)
Other expenses, net	(3)	(3)
Net loss	$ (5,647)	$ (3,556)
Net loss per share - basic and diluted	$ (0.08)	$ (0.07)
Weighted-average shares outstanding - basic and diluted	68,113	47,566