Income Taxes

The Company’s financial statements include total tax benefit of $0, $0 and $1,166 on net losses from continuing operations before taxes of $29,989, $28,338 and $6,769 for the years ended December 31, 2016, 2015 and 2014, respectively. Reconciliations of the differences between the benefit for income taxes and income taxes at the statutory U.S. federal income tax rate is as follows:



	Years Ended December 31,
	2016					2015					2014
	Amount			Percent of Pretax Income		Amount			Percent of Pretax Income		Amount			Percent of Pretax Income
Income taxes from continuing operations at statutory rate	$	(10,196	)	34.0	%	$	(9,635	)	34.0	%	$	(2,301	)	34.0	%
State income taxes	(1,287		)	4.3	%	(196		)	0.7	%	(471		)	7.0	%
Stock warrant derivative liability	—			—		—			—		(3,427		)	50.6	%
Stock-based compensation	215			(0.8	)%	15			(0.1	)%	268			(4.0	)%
R&D tax credits	(955		)	3.2	%	(1,152		)	4.1	%	(320		)	4.7	%
Loss on sale of discontinued operations, net of reduction in related valuation allowances	—			—		(1,458		)	5.1	%	—			—
Warrants issuance	730			(2.4	)%	—			—		—			—
Other	719			(2.4	)%	(127		)	0.5	%	(190		)	2.8	%
Increase in valuation allowance	10,774			(35.9	)%	12,553			(44.3	)%	5,275			(77.9	)%
Total income tax benefit	$	—		—	%	$	—		—	%	$	(1,166	)	17.2	%

The components of deferred tax assets and liabilities as of December 31, 2016 and 2015 are as follows:



	December 31,
	2016			2015
Current deferred tax assets:
Accrued expenses	$	215		$	783
Stock-based compensation	1,664			1,507
Other	39			19
	1,918			2,309
Noncurrent deferred tax assets (liabilities);
Net operating loss carryforwards	53,173			42,358
Research and development credits	4,185			3,836
	57,358			46,194
Total deferred tax assets	59,276			48,503
Valuation allowances	(59,276		)	(48,503		)
Net deferred tax assets	$	—		$	—

As of December 31, 2016 and 2015, the Company had available federal net operating loss ("NOL") carryforwards of approximately $144,374 and $117,272, respectively, North Carolina net economic loss ("NEL") carryforwards of approximately $110,954 and $117,721, respectively, and New Jersey NOL carryforwards of approximately $28,255 and $0, respectively. The federal NOL and North Carolina NEL carryforwards begin to expire in 2020 and 2015, respectively. The New Jersey NOL carryforwards begin to expire in 2036. As of December 31, 2016, the Company had available federal research and development credit carryforwards of $4,022 and North Carolina credit carryforwards of $156, which begin to expire in 2020 and 2015, respectively.

As of December 31, 2016 and 2015, the Company has concluded that it is more likely than not that the Company will not realize the benefit of its deferred tax assets due to its history of losses. Accordingly, the net deferred tax assets have been fully reserved.

In accordance with Section 382 of the Internal Revenue Code of 1986, as amended, a change in equity ownership of greater than 50% within a three-year period results in an annual limitation on the Company’s ability to utilize its NOL carryforwards created during the tax periods prior to the change in ownership. The Company has determined that ownership changes have occurred and as a result, a portion of the Company’s NOL carryforwards are limited.

Because the Company has incurred cumulative net operating losses since inception, all tax years remain open to examination by U.S. federal and state income tax authorities.

The Company adopted FASB Accounting Standards Codification 740-10-25-5, Income Taxes, formerly FASB Interpretation No. 48, Accounting for Uncertainty in Income Taxes, as amended, on January 1, 2009. The difference between the tax benefit recognized in the financial statements and the tax benefit claimed in the tax return is referred to as an unrecognized tax benefit.

The following is a tabular reconciliation of the total amounts of unrecognized tax benefits as of December 31, 2016 and 2015:



	December 31,
	2016		2015
Unrecognized tax benefit—January 1	$	623	$	623
Additions for tax positions of current period	—		—
Additions for tax positions of prior periods	—		—
Other	—		—
Unrecognized tax benefit—December 31	$	623	$	623

None of the unrecognized tax benefits would, if recognized, affect the effective tax rate because the Company has recorded a valuation allowance to fully offset federal and state deferred tax assets. The Company has no tax positions for which it is reasonably possible that the total amount of unrecognized tax benefits will significantly increase or decrease within the coming year. The Company has $0 provided for interest and penalties associated with uncertain tax positions.