Condensed Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating activities
Net loss	$ (1,965,266)	$ (1,982,786)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	378,959	393,775
Change in fair value of warrant liability		(433,392)
Change in operating assets and liabilities:
Prepaid expenses and other assets	142,299	83,682
Accounts payable and other current liabilities	(482,878)	(879,245)
Net cash used in operating activities	(1,926,886)	(2,817,966)
Financing activities
Proceeds from issuance of common stock, net	636,432	544,643
Net cash provided by financing activities	636,432	544,643
Net decrease in cash and cash equivalents	(1,290,454)	(2,273,323)
Cash and cash equivalents at beginning of period	5,319,004	7,679,267
Cash and cash equivalents at end of period	$ 4,028,550	5,405,944
Non-cash financing activities
Reclassification of warrant liability to equity due to amendment of warrants		$ 3,267,885