Statements of Operations - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Operating expenses:
Research and development	$ 4,095,014	$ 7,137,493
General and administrative	3,919,671	4,093,189
Total operating expenses	8,014,685	11,230,682
Loss from operations	(8,014,685)	(11,230,682)
Other income (expense):
Interest income	15,213	6,519
Gain (loss) from change in fair value of warrant liability	433,392	(1,005,349)
Total other income (expense)	448,605	(998,830)
Net loss	$ (7,566,080)	$ (12,229,512)
Net loss per share of common stock, basic	$ (0.46)	$ (0.82)
Net loss per share of common stock, diluted	$ (0.46)	$ (0.90)
Weighted-average shares used to compute basic net loss per share	16,602,422	14,897,885
Weighted-average shares used to compute diluted net loss per share	16,602,422	14,951,036