Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Significant Component of Deferred Tax Assets

Significant components of the Company’s deferred tax assets at December 31, 2015 and 2014 are as follows:

	December 31,
(in thousands)	2015			2014
Net operating loss carryforwards	$	96,215		$	79,050
Start-up and organizational costs		64,942			38,562
Research and development credit carryforwards		29,564			26,112
Stock compensation		1,997			1,181
Capitalized acquisition costs		10,429			11,376
Deferred revenue		2,695			534
Depreciation		251			208
Other		1,673			1,547
		207,766			158,570
Less valuation allowance		(207,766	)		(158,570	)
Effective tax rate	$	—		$	—

Reconciliation of Income Tax Expense (Benefit)

A reconciliation of income tax expense (benefit) at the statutory federal income tax rate and income taxes as reflected in the financial statements is as follows:

	Year Ended December 31,
(in thousands)	2015			2014			2013
Federal income tax at statutory rates		34	%		34	%		34	%
State income tax, net of federal tax benefit		5	%		2	%		4	%
Research and development credits		3	%		3	%		9	%
Stock compensation		-1	%		-4	%		-2	%
Other		0	%		-4	%		1	%
Increase in valuation allowance		-41	%		-31	%		-46	%
Effective tax rate		0	%		0	%		0	%

Summary of Adjustments to Uncertain Tax Position

A summary of the company’s adjustments to its uncertain tax positions in the years ended December 31, 2015, 2014, and 2013 are as follows:

(in thousands)
Balance at December 31, 2012	$	275
Increase/Decrease for tax positions related to the current year		—
Increase/Decrease for tax positions related to prior years		(37	)
Decrease for settlements with applicable taxing authorities		—
Decrease for lapses of statute of limitations		—
Balance at December 31, 2013	$	238
Increase/Decrease for tax positions related to the current year		—
Increase/Decrease for tax positions related to prior years		—
Decrease for settlements with applicable taxing authorities		—
Decrease for lapses of statute of limitations		—
Balance at December 31, 2014	$	238
Increase/Decrease for tax positions related to the current year		—
Increase/Decrease for tax positions related to prior years		—
Decreases for settlements with applicable taxing authorities		—
Decrease for previous year’s lapses of statute of limitations		(20	)
Decrease for impact of §382 limitations		(218	)
Decrease for lapses of statute of limitations		—
Balance at December 31, 2015	$	—