CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues:
License and milestone fees	$ 31,080	$ 76	$ 49,810	$ 10,153
Non-cash royalty revenue related to the sale of future royalties	6,439	5,944	14,052	13,324
Research and development support	902	1,335	2,380	2,394
Clinical materials revenue	599	53	1,277	1,251
Total revenues	39,020	7,408	67,519	27,122
Operating Expenses:
Research and development	35,319	38,652	68,207	74,746
General and administrative	8,836	9,298	16,955	20,533
Restructuring charges			386
Total operating expenses	44,155	47,950	85,548	95,279
Loss from operations	(5,135)	(40,542)	(18,029)	(68,157)
Investment income, net	143	106	258	214
Non-cash interest expense on liability related to the sale of future royalties and convertible senior notes	(3,501)	(4,956)	(7,076)	(9,928)
Interest expense on convertible senior notes	(1,125)	(138)	(2,250)	(138)
Other income, net	751	(392)	885	159
Net loss	$ (8,867)	$ (45,922)	$ (26,212)	$ (77,850)
Basic and diluted net loss per common share (in dollar per share)	$ (0.10)	$ (0.53)	$ (0.30)	$ (0.89)
Basic and diluted weighted average common shares outstanding (in shares)	87,174	87,062	87,167	87,029
Total comprehensive loss	$ (8,867)	$ (45,922)	$ (26,212)	$ (77,850)