Condensed Statements of Operations (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Operating expenses:
Research and development	$ 625,497	$ 2,717,698	$ 3,399,654	$ 5,505,953
General and administrative	897,060	984,047	2,846,611	3,065,595
Total operating expenses	1,522,557	3,701,745	6,246,265	8,571,548
Loss from operations	(1,522,557)	(3,701,745)	(6,246,265)	(8,571,548)
Other income (expense):
Interest income	3,089	2,822	7,425	5,452
Change in fair value of warrant liability		(1,544,138)	433,392	(3,354,973)
Total other income (expense)	3,089	(1,541,316)	440,817	(3,349,521)
Net loss	$ (1,519,468)	$ (5,243,061)	$ (5,805,448)	$ (11,921,069)
Net loss per share of common stock, basic	$ (0.09)	$ (0.34)	$ (0.36)	$ (0.81)
Net loss per share of common stock, diluted	$ (0.09)	$ (0.34)	$ (0.36)	$ (0.84)
Weighted-average shares used to compute basic net loss per share	17,129,649	15,351,295	16,327,385	14,740,977
Weighted-average shares used to compute diluted net loss per share	17,129,649	15,351,295	16,327,385	14,766,853