Stock-Based Compensation and Warrants (Tables)

12 Months Ended

Dec. 31, 2019

Stock-Based Compensation and Warrants

Summary of assumptions used for awards

	Year ended December 31,
	2019			2018
Exercise price	$	0.42		$	0.69
Expected dividends		—	%		—	%
Expected volatility		84	%		86	%
Risk free interest rate		1.61	%		2.75	%
Expected life of option (years)		4.5			4.0

Summary of stock option activity

A summary of stock option activity for the years ended December 31, 2019 and 2018 is as follows:

		Weighted		Weighted Average	Aggregate
		Average Exercise		Remaining	Intrinsic
	Options	Price		Contractual Life	Value
Balance - December 31, 2017	359,076	$	53.93	4.60 years	$	1,800
Granted	671,500		0.69
Exercised	—		—		$	—
Expired	(78,667)		67.02
Forfeited	(12,927)		23.72
Balance - December 31, 2018	938,982	$	15.18	6.19 years	$	—
Granted	1,725,000		0.42
Exercised	—		—		$	—
Expired	(94,738)		58.25
Forfeited	(67,232)		5.95
Balance -December 31, 2019 - outstanding	2,502,012	$	3.62	6.51 years	$	153,353
Balance -  December 31, 2019 - exercisable	358,949	$	21.92	5.18 years	$	—
Grant date fair value of options granted - December 31, 2019		$	470,000
Weighted average grant date fair value - December 31, 2019		$	0.27
Grant date fair value of options granted - December 31, 2018		$	301,000
Weighted average grant date fair value - December 31, 2018		$	0.45

Schedule of options outstanding and exercisable

The options outstanding and exercisable at December 31, 2019 are as follows:

Options Outstanding					Options Exercisable
				Weighted				Weighted
		Weighted		Average		Weighted		Average
		Average		Remaining		Average		Remaining
Range of		Exercise		Contractual		Exercise		Contractual
Exercise Price	Options	Price		Life	Options	Price		Life
$0.00 – $40.00	2,431,708	$	1.38	6.58 years	288,645	$	7.56	5.46 years
41.00 – $70.00	8,364		50.29	3.60 years	8,364		50.29	3.60 years
$71.00 – $102.00	61,940	$	85.02	4.07 years	61,940	$	85.02	4.07 years

Summary of assumptions used by the company

The assumptions used by the Company are summarized in the following table:

	Issuance
		Date
Closing stock price	$	0.88
Expected dividends		—	%
Expected volatility		90	%
Risk free interest rate		3.01	%
Expected life of warrant (years)		5.00

The assumptions used by the Company are summarized in the following table:

	Series A
	December 31,			November 18,
	2018			2016
Closing stock price	$	0.56		$	31.15
Expected dividends		—	%		—	%
Expected volatility		92.50	%		85.00	%
Risk free interest rate		2.50	%		1.58	%
Expected life of warrant (years)		1.9			4.0

	December 31,			October 10,
	2018			2014
Closing stock price	$	0.56		$	61.25
Expected dividends		—	%		—	%
Expected volatility		110.00	%		95.00	%
Risk free interest rate		2.60	%		1.39	%
Expected life of warrant (years)		0.79			5.00

The assumptions used by the Company are summarized in the following table:

Closing stock price	$	18.55
Expected dividends		—	%
Expected volatility		85	%
Risk free interest rate		2.42	%
Expected life of warrant (years)		4.92

Schedule of estimated fair value of the warrant liability

The following table summarizes the estimated fair value of the warrant liability (in thousands):

Balance at December 31,2017	$	4,083
Change in fair value of warrant liability		(4,083)
Balance at December 31,2018		—
Change in fair value of warrant liability		—
Balance at December 31,2019	$	—

Summary of all warrant activity

A summary of all warrant activity for the Company for the years ended December 31, 2019 and 2018 is as follows:

	Number of	Weighted Average
	Warrants	Exercise Price
Balance at December 31,2017	915,138	$	52.50
Granted	18,000,713		1.38
Exercised	—		—
Forfeited	—		—
Balance at December 31,2018	18,915,851		3.85
Granted	—		—
Exercised	—		—
Forfeited	(200,852)		61.25
Balance at December 31,2019	18,714,999	$	3.24

Summary of all outstanding and exercisable warrants

A summary of all outstanding and exercisable warrants as of December 31, 2019 is as follows:

				Weighted Average
		Warrants	Warrants	Remaining
Exercise Price		Outstanding	Exercisable	Contractual Life
$	1.38	17,999,999	17,999,999	3.78 years
	18.20	714	714	2.99 years
	50.05	714,286	714,286	0.88 years
$	3.24	18,714,999	18,714,999	3.67 years