CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Revenue:
Government contracts	$ 0	$ 1,946
Research and development collaborations	5,680	2,272
Total revenue	5,680	4,218
Expenses:
Research and development	37,654	68,952
General and administrative	8,852	10,528
Total expenses	46,506	79,480
Loss from operations	(40,826)	(75,262)
Other income (expense):
Investment income	474	473
Interest expense	(3,513)	(2,430)
Other income (expense)	11	(33)
Net loss	$ (43,854)	$ (77,252)
Basic and diluted net loss per share	$ (0.16)	$ (0.29)
Basic and diluted weighted average number of common shares outstanding	274,178	270,179