CONDENSED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Operating expenses:
Research and development (includes related party amounts of $358, $229, $598, and $499, respectively)	$ 10,425	$ 3,387	$ 19,989	$ 5,152
General and administrative (includes related party amounts of $76, $71, $158, and $136, respectively)	3,040	602	5,395	1,027
Total operating expenses	13,465	3,989	25,384	6,179
Loss from operations	(13,465)	(3,989)	(25,384)	(6,179)
Other income (expense):
Change in fair value of preferred stock purchase right liability		(14)		(14)
Interest income, net	1,095		2,163
Net loss	$ (12,370)	$ (4,003)	$ (23,221)	$ (6,193)
Net loss per common share, basic and diluted	$ (0.39)	$ (4.21)	$ (0.74)	$ (6.54)
Weighted average common shares outstanding, basic and diluted	31,561,445	951,066	31,496,114	946,854

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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