Share-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2017

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

The compensation expense related to the Company’s share-based compensation arrangements is recorded as components of general and administrative expense and research and development expense, as follows:

	Nine Month Period Ended
	September 30,
	2017		2016
Research and development	$	225,342	$	578,626
General and administrative		290,895		1,622,775
Share-based compensation expense	$	516,237	$	2,201,401
Net share-based compensation expense, per common share:
Basic and diluted	$	0.01	$	0.05

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

Following are the weighted-average assumptions used in valuing the stock options granted during the nine-month periods ended September 30, 2017 and 2016:

	Nine Month Period Ended
	September 30,
	2017			2016
Expected volatility		78.92	%		83.03	%
Risk-free interest rate		1.97	%		1.31	%
Expected term of option		6.34 years			5.41 years
Forfeiture rate		-			3.00	%*
Expected dividend yield		0.00	%		0.00	%

* - In 2016, authoritative guidance required forfeitures to be estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. During the nine-month period ended September 30, 2016, forfeitures were estimated at 3%.

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

A summary of the Company’s stock option plans and of changes in options outstanding under the plans for the nine months ended September 30, 2017 is as follows:

			Weighted
			Average
	Number of		Exercise
	Options		Price
Outstanding at January 1, 2017		9,535,306	$	1.57
Granted		3,699,500	$	1.04
Exercised		-	$	-
Expired		(992,802)	$	1.64
Forfeited		-	$	-
Outstanding at September 30, 2017		12,242,004	$	1.41
Exercisable at September 30, 2017		8,330,511	$	1.59