Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Revenues
License revenue	$ 455	$ 328
Reagent sales		59
Grant revenue		6
Total revenues	455	393
Costs of revenues
Licensing costs	91	66
Costs of reagent sales		30
Research and development	16,619	6,183
General and administrative	6,622	5,479
Other operating expenses (income)	45	(114)
Total operating expenses	23,377	11,644
Loss from operations	(22,922)	(11,251)
Other Income
Investment income	929	483
Total other income	929	483
Net loss	(21,993)	(10,768)
Other Comprehensive Income (Loss)
Unrealized gain (loss) on available-for-sale securities, net of reclassifications of $480 for the three months ended March 31, 2017	(539)	994
Total other comprehensive income (loss)	(539)	994
Comprehensive loss	(22,532)	(9,774)
Net loss applicable to common stockholders	$ (21,993)	$ (10,768)
Basic and diluted net loss per common share	$ (0.82)	$ (0.41)
Weighted-average basic and diluted common shares	26,673	26,327