CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues:
License and milestone fees	$ 672	$ 79	$ 13,533	$ 49,889
Non-cash royalty revenue related to the sale of future royalties	8,441	6,503	22,873	20,555
Research and development support	388	650	1,159	3,030
Clinical materials revenue	1,427	1,248	2,465	2,525
Total revenues	10,928	8,480	40,030	75,999
Operating Expenses:
Research and development	47,243	31,689	130,775	99,896
General and administrative	8,347	7,908	26,994	24,863
Restructuring charge	870		3,287	386
Total operating expenses	56,460	39,597	161,056	125,145
Loss from operations	(45,532)	(31,117)	(121,026)	(49,146)
Investment income, net	1,369	293	2,845	551
Non-cash interest expense on liability related to the sale of future royalties and convertible senior notes	(2,546)	(3,385)	(8,203)	(10,461)
Interest expense on convertible senior notes	(23)	(762)	(70)	(3,012)
Non-cash debt conversion expense		(22,191)		(22,191)
Other (expense) income, net	(75)	480	(590)	1,365
Net loss	$ (46,807)	$ (56,682)	$ (127,044)	$ (82,894)
Basic and diluted net loss per common share (in dollar per share)	$ (0.32)	$ (0.61)	$ (0.92)	$ (0.93)
Basic and diluted weighted average common shares outstanding (in shares)	147,220	93,001	137,472	89,133
Total comprehensive loss	$ (46,807)	$ (56,682)	$ (127,044)	$ (82,894)