Selected Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2017

Selected Quarterly Financial Information [Abstract]

Schedule of Selected Quarterly Results from Operations

Selected quarterly results from operations for the years ended December 31, 2017 and 2016 are as follows (in thousands, except per share amounts):

	2017 Quarter Ended
	March 31,			June 30,			September30,			December31,
Grant revenues	$	982		$	1,479		$	1,261		$	1,483
Loss from operations		(6,331	)		(6,720	)		(7,998	)		(6,627	)
Net loss		(6,247	)		(6,632	)		(7,874	)		(6,483	)
Basic and diluted net loss per common share	$	(0.47	)	$	(0.47	)	$	(0.48	)	$	(0.39	)

	2016 Quarter Ended
	March 31,			June 30,			September30,			December31,
Grant revenues	$	859		$	1,373		$	1,149		$	1,247
Loss from operations		(4,567	)		(5,495	)		(6,301	)		(5,543	)
Net loss		(4,547	)		(5,430	)		(6,238	)		(5,483	)
Basic and diluted net loss per common share	$	(7.10	)	$	(0.46	)	$	(0.47	)	$	(0.41	)