Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenues:
Collaborative agreements	$ 338	$ 627	$ 2,130	$ 799
Subscription and license fees	38	49	38	154
Total revenues	376	676	2,168	953
Operating expenses:
Research and development, including stock-based compensation of $868, $940, $1,972 and $2,398, respectively	20,769	21,187	41,634	45,140
Increase (decrease) in fair value of Symphony Icon, Inc. purchase liability	(12)	448	1,741	1,590
General and administrative, including stock-based compensation of $920, $900, $1,769 and $1,692, respectively	6,307	5,152	12,008	10,806
Total operating expenses	27,064	26,787	55,383	57,536
Loss from operations	(26,688)	(26,111)	(53,215)	(56,583)
Interest expense	(1,655)	(455)	(3,357)	(912)
Interest and other income, net	269	538	422	632
Consolidated net loss	$ (28,074)	$ (26,028)	$ (56,150)	$ (56,863)
Consolidated net loss per common share, basic and diluted	$ (0.27)	$ (0.35)	$ (0.54)	$ (0.77)
Shares used in computing consolidated net loss per common share, basic and diluted	103,608	73,518	103,562	73,470
Unrealized gain (loss) on investments	$ 75	$ (5)	$ 161	$ 3
Comprehensive loss	$ (27,999)	$ (26,033)	$ (55,989)	$ (56,860)