Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenues:
Collaboration agreements	$ 3,711	$ 12,671
Research grants	231	820
Total revenues	3,942	13,491
Operating expenses:
Research and development	15,266	14,980
General and administrative	5,357	4,732
Total operating expenses	20,623	19,712
Loss from operations	(16,681)	(6,221)
Interest and other income, net	187	154
Loss before income taxes	(16,494)	(6,067)
Benefit from income taxes		748
Net loss	$ (16,494)	$ (5,319)
Basic and diluted net loss per share	$ (0.23)	$ (0.08)
Shares used in computing basic and diluted net loss per share	70,373	69,283