CONDENSED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Revenues:
License fees and royalties	$ 57	$ 318
Operating expenses:
Research and development	5,906	2,440
General and administrative	5,452	5,315
Total operating expenses	11,358	7,755
Loss from operations	(11,301)	(7,437)
Interest and other income	1,162	394
Change in fair value of equity investment	98	(125)
Other expense	(18)	(18)
Net loss	$ (10,059)	$ (7,186)
Basic and diluted net loss per share	$ (0.05)	$ (0.04)
Shares used in computing basic and diluted net loss per share	186,393,128	160,525,947

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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