CONDENSED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenues:
License fees and royalties	$ 43	$ 101	$ 95	$ 158
Operating expenses:
Research and development	10,845	10,134	21,647	16,040
General and administrative	5,960	5,191	12,080	10,643
Total operating expenses	16,805	15,325	33,727	26,683
Loss from operations	(16,762)	(15,224)	(33,632)	(26,525)
Interest and other income	475	1,113	1,229	2,275
Change in fair value of equity investment	422	(98)	227
Other expense	41	(30)	(3)	(48)
Net loss	$ (15,824)	$ (14,239)	$ (32,179)	$ (24,298)
Basic and diluted net loss per share	$ (0.06)	$ (0.08)	$ (0.14)	$ (0.13)
Shares used in computing basic and diluted net loss per share	246,966,143	186,556,082	223,594,118	186,475,055