Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Revenue	$ 1,912	$ 1,250	$ 3,461	$ 1,820
Operating expenses:
Research and development	18,397	11,034	34,527	19,363
General and administrative	8,474	5,485	16,627	10,778
Other operating (income) expense, net	(6,744)	8	72	2,304
Total operating expenses	20,127	16,527	51,226	32,445
Operating loss	(18,215)	(15,277)	(47,765)	(30,625)
Interest expense, net	(2,388)	(1,351)	(4,326)	(2,660)
Net loss	$ (20,603)	$ (16,628)	$ (52,091)	$ (33,285)
Net loss per share attributable to holders of common stock:
Net loss per common share - basic and diluted	$ (1.38)	$ (1.35)	$ (3.58)	$ (2.73)
Weighted-average shares outstanding:
Weighted-average common shares used to compute basic and diluted net loss per common share	14,981,756	12,355,969	14,556,986	12,178,376

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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