Income Taxes (Tables)

12 Months Ended

Dec. 31, 2013

Income Tax Disclosure [Abstract]

Reconciliation of Statutory Federal Income Tax Rate and Effective Income Tax Rate

A reconciliation of the statutory Federal income tax rate and the effective income tax rate for the year ended December 31, 2013 and 2012 follows:

	December 31, 2013			December 31, 2012
Statutory federal income tax rate		35	%		35	%
Permanent items		(12	)%		(8	)%
State income taxes, net of federal taxes		4	%		4	%
Change in valuation allowance		(30	)%		(30	)%
Tax credits claimed		2	%		1	%
Other		1	%		(2	)%
Effective income tax rate		0	%		0	%

Summary of Significant Components of Deferred Tax Assets and Liabilities

Significant components of deferred tax assets and liabilities are as follows (in thousands):

	December 31, 2013			December 31, 2012
Deferred tax assets (liabilities)
Current deferred tax assets (liabilities)	$	298		$	120
Deferred revenues		—			—
Current deferred tax assets		298			120
Valuation allowances		(298	)		(120	)
Net current deferred tax assets	$	—		$	—
Net operating loss carryforwards		19,224			17,150
Stock based compensation		2,987			2,532
Research and development tax credit		1,627			1,206
Other		51			10
Non-current deferred tax assets		23,889			20,898
Valuation allowances		(23,884	)		(20,882	)
Net non-current deferred tax assets		5			16
Non-current deferred tax liabilities		(5	)		(16	)
Net deferred tax assets	$	—		$	—

Summary of Components of Provision for Income Taxes

The components of the provision for income taxes were as follows:

	December 31, 2013		December 31, 2012
Current	$	—	$	—
Deferred		—		—
Total	$	—	$	—