Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Income Taxes [Abstract]

Components of Deferred Tax Assets

Significant components of our deferred tax assets and liabilities are as follows:

	December 31,
	2015		2014
Deferred tax assets/(liabilities)
Net operating loss carry-forwards	$	65,425,000	$	61,332,000
Research and orphan drug credit carry-forwards		5,181,000		3,855,000
Depreciation and amortization		(3,000)		(8,000)
Stock options and other		479,000		1,381,000
Intangible assets		(3,079,000)		(3,155,000)
Net deferred tax assets/(liabilities)		68,003,000		63,405,000
Valuation allowance for deferred tax assets		(71,008,000)		(66,483,000)
Net deferred tax assets/(liabilities)	$	(3,005,000)	$	(3,078,000)

Reconciliation of Statutory to Effective Tax Rates

	December 31,
	2015		2014
Percent of pre-tax income:
U.S. federal statutory income tax rate	34.0	%	34.0	%
Warrant liability and preferred stock conversion liability	573.8	%	(54.9)	%
Difference in foreign vs U.S. statutory rates	(21.8)	%	-	%
Stock option forfeitures & expirations	(138.2)	%	-	%
State taxes, net of federal benefit	-	%	3.7	%
Non-deductible stock issuance costs	(17.9)	%	-	%
R&D expenses associated with Australian research grants	27.8	%	-	%
Effect of tax rate changes	12.4	%		%
All other	(2.9)	%	1.0	%
Subtotal	467.2	%	(16.2)	%
Change in valuation allowance	(454.8)	%	16.2	%
Effective income tax rate	12.4	%	0.00	%