CONDENSED STATEMENTS OF OPERATIONS (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenue:
License revenue	$ 0	$ 0	$ 0	$ 100,000
Expenses:
Research and development	4,755,191	8,927,037	17,675,079	29,531,609
General and administrative	3,418,808	2,771,732	9,534,872	12,859,069
Total expenses	8,173,999	11,698,769	27,209,951	42,390,678
Loss before other income (loss)	(8,173,999)	(11,698,769)	(27,209,951)	(42,290,678)
Other income (loss):
Interest income	119,900	68,635	271,292	195,809
Interest expense	(828,120)	(781,038)	(2,999,230)	(1,939,186)
Other (loss), net	(6,055)	(10,489)	(16,722)	(4,398)
Gain (loss) on warrant derivative liabilities	3,763,855	246,211	(572,209)	939,668
Net loss	$ (5,124,419)	$ (12,175,450)	$ (30,526,820)	$ (43,098,785)
Basic and diluted net loss per share (in dollars per share)	$ (0.19)	$ (0.80)	$ (1.33)	$ (3.45)
Basic and diluted weighted-average shares outstanding (in shares)	26,618,098	15,173,742	22,936,843	12,500,295