DERIVATIVE WARRANT LIABILITY (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2017

Dec. 31, 2016

DERIVATIVE WARRANT LIABILITY (Tables) [Line Items]

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

The underlying assumptions used in the binomial model to determine the fair value of the derivative warrant liability were:

	Three months ended
	September 30, 2017	June 30, 2017	March 31, 2017
Stock price on valuation date	$1.43	$1.37 – 2.20	$2.21 – 3.25
Risk-free interest rate	1.5%	1.3 – 1.4%	1.3 – 1.5%
Expected dividend yield	–	–	–
Expected term (in years)	2.0	2.2 – 2.5	2.5 – 2.7
Expected volatility	128%	131 – 134%	146 – 153%
Number of iterations	5	5	5

The underlying assumptions used in the binomial model to determine the fair value of the derivative warrant liability were:

		September 21, 2016		December 31, 2016
Current stock price	$	1.20	$	3.20
Risk-free interest rate		0.92 %		1.50 %
Expected dividend yield		–		–
Expected term (in years)		3.0		2.7
Expected volatility		146 %		153 %
Number of iterations		5		5

		May 1, 2015		May 4, 2015		December 31, 2014
Current stock price	$	3.75	$	3.50	$	5.02
Risk-free interest rate		0.60 %		0.60 %		0.60 %
Expected dividend yield		–		–		–
Expected term (in years)		1.8		1.8		3.0
Expected volatility		133 %		133 %		129 %
Early exercise factor		1.33		1.33		1.33

Schedule of Derivative Liabilities at Fair Value [Table Text Block]

The initial fair value of the derivative warrant liability was recorded as follows:

Extinguishment of debt	$	1,715,000
Interest expense		5,189,000
Debt discount		2,450,000
Initial fair value of warrants issued	$	9,354,000

Derivative Instruments, Gain (Loss) [Table Text Block]

Changes in the derivative warrant liability were as follows:

December 31, 2016	$	23,120,000
Decrease in fair value		(10,580,000)
Reclassification to additional paid-in capital upon exercise of warrants		(7,301,000)
September 30, 2017	$	5,239,000

12% Warrants [Member]

DERIVATIVE WARRANT LIABILITY (Tables) [Line Items]

Derivative Instruments, Gain (Loss) [Table Text Block]

Changes in the derivative warrant liability were as follows:

January 1, 2016	$	–
Initial fair value of warrants issued		9,354,000
Increase in fair value		17,284,000
Reclassification to additional paid-in capital upon exercise of warrants		(3,518,000)
December 31, 2016	$	23,120,000

Series C Warrants [Member]

DERIVATIVE WARRANT LIABILITY (Tables) [Line Items]

Derivative Instruments, Gain (Loss) [Table Text Block]

Changes in the derivative warrant liability and cumulative expense were as follows:

		Liability		Cumulative Expense (Gain)
December 31, 2014	$	3,893,904	$	3,393,904
Increase in the fair value of warrant liability		14,010		14,010
Reclassification to additional paid-in capital upon exercise of warrants		(3,683,270)		–
Gain on settlement of derivative		(224,644)		(224,644)
December 31, 2015	$	–	$	3,183,270