DERIVATIVE WARRANT LIABILITY (Tables)

9 Months Ended

Sep. 30, 2017

Disclosure Text Block [Abstract]

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

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