Selected Quarterly Information (Unaudited)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Selected Quarterly Information (Unaudited)

15. Selected Quarterly Information (Unaudited)

       (in thousands, except per share amount)

Year Ended December 31, 2018	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenue	$	146		$	—		$	—		$	—
Total operating expenses		16,342			12,378			12,570			12,762
Loss from operations		(16,196	)		(12,378	)		(12,570	)		(12,762	)
Preferred stock dividends		(5,120	)		(5,462	)		(6,074	)		(342	)
Settlement of a related party relationship		—			—			—			207,361
Net income (loss) applicable to common shareholders		(21,540	)		(17,493	)		(18,659	)		194,538
Net income (loss) per share, basic	$	(0.15	)	$	(0.12	)	$	(0.13	)	$	1.29
Net income (loss) per share, diluted	$	(0.15	)	$	(0.12	)	$	(0.13	)	$	1.29

Year Ended December 31, 2017	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
Revenue	$	1,597		$	1,597		$	1,598		$	1,597
Total operating expenses		15,562			14,611			14,676			15,033
Loss from operations		(13,965	)		(13,014	)		(13,078	)		(13,436	)
Preferred stock dividends		(4,171	)		(4,865	)		(4,903	)		(4,999	)
Net (loss) applicable to common shareholders		(19,658	)		(17,727	)		(17,604	)		(18,272	)
Loss per share, basic and diluted	$	(0.15	)	$	(0.13	)	$	(0.13	)	$	(0.12	)