FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)

6 Months Ended

12 Months Ended

Jun. 30, 2016

Dec. 31, 2015

Fair Value Disclosures [Abstract]

Fair Value Hierarchy for Liabilities Measured at Fair Value on Recurring Basis

The Company has determined the fair value of certain liabilities using the market approach. The following table presents the Company’s fair value hierarchy for these liabilities measured at fair value on a recurring basis as of June 30, 2016:

			Quoted Market
			Prices in Active		Significant Other		Significant Other
	Fair Value		Markets		Observable Inputs		Unobservable Inputs
	June 30, 2016		(Level 1)		(Level 2)		(Level 3)
Liabilities:
Warrant liability - 2012 Series A	$	1,565,827	$	-	$	-	$	1,565,827
Warrant liability - 2012 placement agent		3,689		-		-		3,689
Warrant liability - 2013 Series D		2,958,572		-		-		2,958,572
Warrant liability - 2013 placement agent		2,823		-		-		2,823
Total	$	4,530,911	$	-	$	-	$	4,530,911

The following table presents the Company’s fair value hierarchy for these liabilities measured at fair value on a recurring basis as of December 31, 2015:

			Quoted Market Prices in Active		Significant Other		Significant Other
	Fair Value		Markets		Observable Inputs		Unobservable Inputs
	December 31, 2015		(Level 1)		(Level 2)		(Level 3)
Liabilities:
Warrant liability - 2012 Series A	$	1,753,969	$	-	$	-	$	1,753,969
Warrant liability - 2012 placement agent		7,661		-		-		7,661
Warrant liability - 2013 Series D		2,985,512		-		-		2,985,512
Warrant liability - 2013 placement agent		3,545		-		-		3,545
Total	$	4,750,687	$	-	$	-	$	4,750,687

The following table presents the Company’s fair value hierarchy for these assets measured at fair value on a recurring basis as of December 31, 2015:

			Quoted Market
			Prices in Active		Significant Other		Significant Other
	Fair Value		Markets		Observable Inputs		Unobservable Inputs
	December 31, 2015		(Level 1)		(Level 2)		(Level 3)
Liabilities:
Warrant liability - 2012 Series A	$	1,753,969	$	-	$	-	$	1,753,969
Warrant liability - 2012 placement agent		7,661		-		-		7,661
Warrant liability - 2013 Series D		2,985,512		-		-		2,985,512
Warrant liability - 2013 placement agent		3,545		-		-		3,545
Total	$	4,750,687	$	-	$	-	$	4,750,687

The following table presents the Company’s fair value hierarchy for these assets measured at fair value on a recurring basis as of December 31, 2014:

			Quoted Market
			Prices in Active		Significant Other		Significant Other
	Fair Value		Markets		Observable Inputs		Unobservable Inputs
	December 31, 2014		(Level 1)		(Level 2)		(Level 3)
Liabilities:
Warrant liability - 2010 Class B	$	28,066	$	-	$	-	$	28,066
Warrant liability - 2012 Series A&B		3,520,319		-		-		3,520,319
Warrant liability - 2012 placement agent		67,246		-		-		67,246
Warrant liability - 2013 Series D&E		3,036,986		-		-		3,036,986
Warrant liability - 2013 placement agent		18,907		-		-		18,907
Total	$	6,671,524	$	-	$	-	$	6,671,524

Summary of Changes in Fair Value of Liabilities

The following table provides a summary of changes in fair value of the Company’s liabilities, as well as the portion of losses included in income attributable to unrealized depreciation that relate to those liabilities held at June 30, 2016:

Fair Value Measurement Using Significant Unobservable Inputs (Level 3)

	Total						2013						2012
	Warrant		2013		2013		Placement		2012		2012		Placement		2010
	Liability		Series E		Series D		Agent		Series B		Series A		Agent		Class B
Balance at January 1, 2015	$	6,671,524	$	25,737	$	3,011,249	$	18,907	$	12,381	$	3,507,938	$	67,246	$	28,066
Total gains or losses:
Unrealized appreciation/(depreciation)		(1,920,837)		(25,737)		(25,737)		(15,362)		(12,381)		(1,753,969)		(59,585)		(28,066)
Balance at December 31, 2015	$	4,750,687	$	-	$	2,985,512	$	3,545	$	-	$	1,753,969	$	7,661	$	-
Total gains or losses:
Unrealized appreciation/(depreciation)		(219,776)				(26,940)		(722)				(188,142)		(3,972)
Balance at June 30, 2016	$	4,530,911	$	-	$	2,958,572	$	2,823	$	-	$	1,565,827	$	3,689	$	-
Value per Warrant	$	0.106	$	-	$	0.123	$	0.043	$	-	$	0.086	$	0.013	$	-

The following table provides a summary of changes in fair value of the Company’s liabilities, as well as the portion of losses included in income attributable to unrealized depreciation that relate to those liabilities held at December 31, 2015:

Fair Value Measurement Using Significant Unobservable Inputs (Level 3)

	Total						2013						2012
	Warrant		2013		2013		Placement		2012		2012		Placement		2010
	Liability		Series E		Series D		Agent		Series B		Series A		Agent		Class B
Balance at January 1, 2014	$	35,864,881	$	5,855,206	$	12,482,527	$	98,080	$	2,816,676	$	13,887,307	$	362,633	$	362,452
Total gains or losses:
Unrealized appreciation		(29,193,357)		(5,829,469)		(9,471,278)		(79,173)		(2,804,295)		(10,379,369)		(295,387)		(334,386)
Balance at December 31, 2014	$	6,671,524	$	25,737	$	3,011,249	$	18,907	$	12,381	$	3,507,938	$	67,246	$	28,066
Total gains or losses:
Unrealized appreciation		(1,920,837)		(25,737)		(25,737)		(15,362)		(12,381)		(1,753,969)		(59,585)		(28,066)
Balance at December 31, 2015	$	4,750,687	$	-	$	2,985,512	$	3,545	$	-	$	1,753,969	$	7,661	$	-
Value per Warrant	$	0.202	$	-	$	0.232	$	0.054	$	-	$	0.170	$	0.027	$	-

Schedule of Derivative Liabilities at Fair Value

Significant assumptions used at December 31, 2015 and 2014 for the warrants and embedded conversion discount derivative liability of the Debentures are as follows:  

	December 31, 2015			December 31, 2014
Volatility		162	%		173	%
Risk-free interest rate		1.38	%		1.65	%