Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Summary of Net Deferred Tax Asset

Our net deferred tax asset consisted of the following at December 31, 2016 and 2015:

	December 31,
	2016			2015
Deferred tax asset:
Net operating loss carryforwards	$	42,436,541		$	42,315,384
Deferred compensation		1,681,158			1,474,625
Depreciation and amortization		842,073			1,010,636
Research and development credits		3,788,955			3,788,752
Accrued expenses		391,365			314,633
Impairment loss		730,831			850,334
Other		438,039			248,933
Total deferred tax assets		50,308,962			50,003,297
Less: Valuation allowance		(50,308,962	)		(50,003,297	)
Net deferred tax asset	$	—		$	—

Summary of Income Tax Provision (Benefit) from Income Taxes

The income tax provision (benefit) from income taxes consists of the following at December 31, 2016 and 2015:

	Years Ended December 31,
	2016			2015
Federal
Current	$	—		$	—
Deferred		(1,069,610	)		(1,246,071	)
State
Current
Deferred		763,945			(213,826	)
Total		(305,665	)		(1,459,897	)
Change in valuation allowance		305,665			1,459,897
Income tax provision (benefit)	$	—		$	—

Summary of Provision for Income Taxes Using Statutory Federal Tax Rate

The provision for income taxes using the statutory federal tax rate as compared to our effective tax rate is summarized as follows:

	December 31,
	2016			2015
Federal income tax rate		(34.0	)%		(34.0	)%
State income tax rate, net of federal benefit		(5.8	)%		(4.8	)%
Deferred tax true-up		(1.7	)%	5.0		%
Other permanent differences		-	%	0.1		%
Net operating loss expiration		31.4	%	-		%
		(10.1	)%		(33.7	)%
Change in valuation allowance		10.1	%		33.7	%
		—	%		—	%