Income Taxes (Tables)

12 Months Ended

Dec. 31, 2014

Loss before Income Tax Attributable to Geographic Location

Loss before income taxes is attributed to the following geographic locations for the years ended December 31,


	2014		2013
United States	$	30,215,000	$	26,080,000
Foreign		2,526,000		359,000

Total loss before income taxes	$	32,741,000	$	26,439,000

Components of Deferred Tax Assets and Liabilities

Significant components of our deferred tax assets and liabilities at December 31 are as follows:


	2014			2013
Deferred tax assets:
Capitalized research and development costs	$	66,212,000		$	59,426,000
Net operating losses		57,261,000			56,906,000
Research and development credits		9,798,000			8,931,000
Stock-based compensation		1,124,000			1,063,000
Capital loss carryover		254,000			541,000
Fixed assets		393,000			452,000
Other		3,930,000			1,289,000

		138,972,000			128,608,000
Valuation allowance		(138,972,000	)		(128,315,000	)

Total deferred tax assets	$	—		$	293,000

Deferred tax liability:
Intangible assets		—			(293,000	)

Total deferred tax liability	$	—		$	(293,000	)

Net deferred tax assets	$	—		$	—

Reconciliation of Federal Income Tax Rate

The effective tax rate as a percentage of income before income taxes differs from the statutory federal income tax rate (when applied to income before income taxes) for the years ended December 31 as follows:


	2014			2013			2012
Statutory federal income tax (benefit) rate		(34	)%		(34	)%		(34	)%
State income tax (benefit) rate		—			—			(3.3	)
Increase resulting from:
Expenses not deductible for taxes		0.8			0.5			8.8
Increase in valuation allowance		32.6			38.8			3.7
Change in state deferred tax rate		0.0			1.1			17.7
Change in foreign deferred tax rate		2.8			0.9			1.8
Expiration of tax attributes		1.7			0.5			5.3
Prior year true up		1.1			(0.7	)		—
Tax credits		(2.4	)		(3.0	)		—
Warrant valuation		(2.5	)		(4.1	)		—

Effective tax (benefit) rate		0	%		0	%		0	%