Unaudited Statements of Operations and Comprehensive Loss - USD ($)	3 Months Ended	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Statements of Operations and Comprehensive Loss
Revenue
Costs and expenses:
Research and development expense	13,065,359	9,302,266	24,838,025	18,323,688
General and administrative expense	3,750,610	2,846,636	7,111,058	5,701,762
Total costs and expenses	16,815,969	12,148,902	31,949,083	24,025,450
Loss from operations	(16,815,969)	(12,148,902)	(31,949,083)	(24,025,450)
Interest income	986,154	870,139	2,035,371	1,233,843
Net loss and comprehensive loss	$ (15,829,815)	$ (11,278,763)	$ (29,913,712)	$ (22,791,607)
Basic and diluted net loss per common share (in dollars per share)	$ (0.37)	$ (0.26)	$ (0.69)	$ (0.58)
Basic and diluted weighted average number of common shares (in shares)	43,183,010	42,809,840	43,174,989	38,982,965

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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