Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue
Grant revenue			$ 4,753
Type of Revenue [Extensible List]	us-gaap:GrantMember	us-gaap:GrantMember	us-gaap:GrantMember	us-gaap:GrantMember
Operating expenses
Research and development	$ 3,840	$ 1,027	$ 10,325	$ 8,065
General and administrative	3,158	5,191	11,039	16,111
Total operating expenses	6,998	6,218	21,364	24,176
Loss from operations	(6,998)	(6,218)	(16,611)	(24,176)
Interest income	232	261	811	703
Other income (expense), net	624	(593)	1,910	(1,906)
Net loss	$ (6,142)	$ (6,550)	$ (13,890)	$ (25,379)
Net loss per share - basic and diluted	$ (0.54)	$ (1.08)	$ (1.23)	$ (4.23)
Weighted-average common shares used to compute basic and diluted net loss per share	11,285	6,040	11,280	5,998

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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