CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Operating expenses:
Research and development	$ 20,644	$ 14,008	$ 50,475	$ 26,426
General and administrative	5,515	2,241	13,550	6,263
Total operating expenses	26,159	16,249	64,025	32,689
Loss from operations	(26,159)	(16,249)	(64,025)	(32,689)
Interest income	1,622	169	2,992	396
Loss before provision for income taxes	(24,537)	(16,080)	(61,033)	(32,293)
Benefit (provision) for income taxes	131	51	386	121
Net loss and comprehensive loss	$ (24,406)	$ (16,029)	$ (60,647)	$ (32,172)
Net loss per share attributable to common shareholders - basic and diluted	$ (0.51)	$ (8.25)	$ (2.62)	$ (19.21)
Weighted average common shares outstanding - basic and diluted	48,183,424	1,942,106	23,174,841	1,675,133

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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