CONDENSED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues:
License fees and royalties	$ 101	$ 208	$ 158	$ 526
Operating expenses:
Research and development	10,134	3,204	16,040	5,644
General and administrative	5,191	4,246	10,643	9,561
Total operating expenses	15,325	7,450	26,683	15,205
Loss from operations	(15,224)	(7,242)	(26,525)	(14,679)
Interest and other income	1,113	717	2,275	1,111
Change in fair value of equity investment	(98)	(350)		(475)
Other expense	(30)	(59)	(48)	(77)
Net loss	$ (14,239)	$ (6,934)	$ (24,298)	$ (14,120)
Basic and diluted net loss per share	$ (0.08)	$ (0.04)	$ (0.13)	$ (0.08)
Shares used in computing basic and diluted net loss per share	186,556,082	174,475,244	186,475,055	167,538,530

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