CONDENSED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
License fees and royalties	$ 131	$ 165	$ 289	$ 691
Operating expenses:
Research and development	11,109	2,707	27,149	8,351
General and administrative	4,994	4,263	15,637	13,824
Total operating expenses	16,103	6,970	42,786	22,175
Loss from operations	(15,972)	(6,805)	(42,497)	(21,484)
Interest and other income	1,021	1,060	3,296	2,171
Change in fair value of equity investment	(195)	205	(195)	(270)
Other expense	(34)	(57)	(82)	(134)
Net loss	$ (15,180)	$ (5,597)	$ (39,478)	$ (19,717)
Basic and diluted net loss per share	$ (0.08)	$ (0.03)	$ (0.21)	$ (0.11)
Shares used in computing basic and diluted net loss per share	189,123,647	184,301,986	187,367,621	173,187,753

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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