Condensed Consolidated Statements of Operations (Unaudited) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Licensing revenue	$ 125,000	$ 125,000	$ 250,000	$ 250,000
Operating expenses:
Research and development	4,593,544	3,046,631	7,334,620	6,521,907
General and administrative	3,542,809	1,649,110	5,207,837	3,117,232
Total operating expenses	8,136,353	4,695,741	12,542,457	9,639,139
Loss from operations	(8,011,353)	(4,570,741)	(12,292,457)	(9,389,139)
Other (expense) income:
Loss from change in valuation of earn-out milestone liability	(277,129)	(292,228)	(547,324)	(575,979)
Investment income	73,461	1,426	147,185	3,417
Interest expense	(15,031)	(29,416)	(15,031)	(91,756)
Other (expense) income	(504)	1,090	76	3,452
Total other (expense) income, net	(219,203)	(319,128)	(415,094)	(660,866)
Net loss	(8,230,556)	(4,889,869)	(12,707,551)	(10,050,005)
Deemed dividend related to warrant modification		(345,685)		(345,685)
Net loss attributable to common shareholders	$ (8,230,556)	$ (5,235,554)	$ (12,707,551)	$ (10,395,690)
Net loss per common share
Basic and diluted	$ (0.46)	$ (0.79)	$ (0.73)	$ (1.75)
Weighted average shares outstanding
Basic and diluted	17,743,229	6,628,778	17,503,796	5,948,570

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