Stockholders' Equity and Convertible Preferred Stock (Tables)

12 Months Ended

Dec. 31, 2018

Stockholders' Equity Note [Abstract]

Schedule of designated separate series of capital stock

The Company had designated separate series of its capital stock as of December 31, 2018 and December 31, 2017 as summarized below:

	Number of Shares Issued
	and Outstanding as of
	December 31, 2018		December 31, 2017		Par Value		Conversion Ratio
Series “A”		—		—	$	0.0001	N/A
Series “C”		—		—		0.0001	0.05:1
Series “D”		4,725		4,725		0.0001	0.53:1
Series “D-1”		834		834		0.0001	0.53:1
Series “F-1”		—		—		0.0001	0.05:1
Series “H”		—		—		0.0001	0.53:1
Series “I”		—		—		0.0001	1.05:1
Series “J”		—		—		0.0001	0.05:1
Series “K”		—		—		0.0001	263.16:1

Schedule of warrant activity

A summary of warrant activity for year ended December 31, 2018 and 2017 is presented below: 

	Warrants		Weighted Average Exercise Price		Total Intrinsic Value		Weighted Average Remaining Contractual Life (in years)
Outstanding as of December 31, 2017		1,249,754	$	8.98	$	—		2.92
Outstanding as of December 31, 2018		1,249,754	$	8.98				1.92

Schedule of fair value of options granted

The fair value of options granted in 2018 and 2017 was estimated using the following assumptions: 

	For the Years Ended December 31,
	2018	2017
Exercise price	$1.04-$1.50	$	1.02
Expected stock price volatility	131.8%-132.2%		134.5	%
Risk-free rate of interest	2.65%-2.80%		1.4	%
Term (years)	9.13-9.34		4.42

Schedule of option activity

A summary of option activity under the Company’s employee stock option plan for year ended December 31, 2018 and 2017 is presented below: 

	Number of Shares		Weighted Average Exercise Price		Total Intrinsic Value		Weighted Average Remaining Contractual Life (in years)
Outstanding as of December 31, 2017		325,597	$	78.20	$	5,999		3.2
Employee options granted		200,000		1.39		—		9.2
Outstanding as of December 31, 2018		525,597	$	48.96	$	—		4.9
Options vested and expected to vest		525,534	$	48.96	$	—		4.9
Options vested and exercisable		500,534	$	51.35	$	—		4.6

A summary of options that the Company granted to non-employees for the year ended December 31, 2018 and 2017 is presented below: 

	Number of Shares		Weighted Average Exercise Price		Total Intrinsic Value		Weighted Average Remaining Contractual Life (in years)
Outstanding as of December 31, 2017		2,893	$	98.07	$	—		3.4
Outstanding as of December 31, 2018		2,893	$	98.07	$	—		2.4
Options vested and expected to vest		2,893	$	98.07	$	—		2.4
Options vested and exercisable		2,893	$	98.07	$	—		2.4

Schedule of stock-based compensation

Stock-based compensation expense for the year ended December 31, 2018 and 2017 was comprised of the following ($ in thousands): 

	For the Years Ended December 31,
	2018		2017
Employee restricted stock awards	$	107	$	—
Non-employee restricted stock awards		—		9
Employee stock option awards		213		14
Total compensation expense	$	320	$	23