Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Revenue:
Revenue	$ 3,189	$ 2,347
Operating expenses:
Research and development	8,110	10,005
General and administrative	6,697	5,695
Change in contingent consideration liability	800	1,900
Total operating expenses	15,607	17,600
Operating loss	(12,418)	(15,253)
Other (expense) income:
Interest (expense) income, net	(1,006)	(1,107)
Total other (expense) income	(1,006)	(1,107)
Net loss	$ (13,424)	$ (16,360)
Net loss per share - basic and diluted (in dollars per share)	$ (0.19)	$ (0.23)
Weighted-average shares - basic and diluted (in shares)	72,517	70,196
Royalty [Member]
Revenue:
Revenue	$ 3,058	$ 2,119
License [Member]
Revenue:
Revenue	130	215
Product and Service, Other [Member]
Revenue:
Revenue	$ 1	$ 13

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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