Condensed Consolidated Statements of Operations (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenue:
Total revenue	$ 3,938,000	$ 6,627,000
Operating expenses:
Research and development	19,530,000	20,128,000
General and administrative	9,182,000	9,045,000
Amortization of intangible assets	140,000	152,000
Total operating expenses	28,852,000	29,325,000
Loss from operations	(24,914,000)	(22,698,000)
Interest income	1,471,000	1,199,000
Other loss	(19,000)	(16,000)
Loss before income tax	(23,462,000)	(21,515,000)
Income tax benefit	35,000	21,000
Net loss	$ (23,427,000)	$ (21,494,000)
Net loss per common share, basic and diluted	$ (0.29)	$ (0.28)
Shares used in computing net loss per common share, basic and diluted	79,673,294	77,906,645
Collaboration and license revenue
Revenue:
Total revenue	$ 3,938,000	$ 6,627,000