Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Operating expenses:
Research and development	$ 3,345	$ 6,150
General and administrative	2,532	4,070
Total operating expenses	5,877	10,220
Loss from operations	(5,877)	(10,220)
Total other income (expense), net	(260)	(447)
Net loss	$ (6,137)	$ (10,667)
Net loss per share attributable to common stock holders, basic and diluted	$ (0.18)	$ (0.36)
Weighted average common stock shares outstanding, basic and diluted	33,823,909	29,795,466

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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