Income Taxes (Tables)

12 Months Ended

Dec. 31, 2012

Schedule Of Income Tax (Expense) Benefit

Income tax (expense) benefit for the periods presented consisted of the following:

	Years Ended December 31,
	2012			2011		2010
Current:
Federal	$	(7	)	$	4,309	$	(5,012	)
State		—			22		3,440
Total current		(7	)		4,331		(1,572	)
Deferred:
Federal		—			—		—
State		—			—		—
Total deferred		—			—		—
Total income tax (expense) benefit	$	(7	)	$	4,331	$	(1,572	)

Schedule Of Reconciliation Of Statutory Federal Income Tax Rate

A reconciliation of the statutory Federal income tax rate of 35% to the Company’s effective income tax rates is as follows:

	Years Ended December 31,
	2012			2011			2010
Federal tax provision at statutory rate		35.00	%		35.00	%		35.00	%
State taxes (net of Federal benefit)		10.81	%		2.27	%		(4.17	%)
Change in tax reserve		(0.06	%)		(0.94	%)		(1.84	%)
Orphan drug credit		0.25	%		(0.70	%)		(1.06	%)
Stock-based compensation		1.50	%		0.06	%		(2.03	%)
Non-deductible stock-based compensation		(1.86	%)		0.20	%		(0.98	%)
Change in valuation allowance		(45.48	%)		(29.94	%)		(39.65	%)
Research and development credits		—			7.05	%		9.72	%
Net proceeds from stockholder securities law settlement		—			(2.43	%)		—
Other		(0.19	%)		(0.53	%)		0.17	%
Benefit (provision) for taxes		(0.03	)%		10.04	%		(4.84	%)

Schedule Of Company's Deferred Tax Assets

Significant components of the Company’s deferred tax assets for Federal and state income taxes are follows:

	December 31,
	2012			2011
Deferred tax assets:
Deferred revenue	$	15,491		$	54,116
Net operating loss carry forward		72,232			30,767
Stock-based compensation		12,721			9,872
Research and development credits		13,897			11,280
Depreciation, amortization and other		109			133
Accruals and reserves		6,530			552
Total deferred tax assets		120,980			106,720
Less: valuation allowance		(98,671	)		(106,720	)
Total net deferred tax assets		22,309			—
Deferred tax liabilities
Convertible Notes		(22,309	)		—
Total deferred tax liabilities		(22,309	)		—
Net deferred tax assets	$	—		$	—
Recorded as:
Net current deferred tax assets (included in “Prepaid expenses and other current assets”)	$	3,800		$	—
Net non-current deferred tax assets		—			—
Net current deferred tax liabilities		—			—
Net non-current deferred tax liabilities (included in “Other non-current liabilities”)		(3,800	)		—
Net deferred tax assets	$	—		$	—

Schedule Of Gross Unrecognized Tax Positions

The following table summarizes activity related to the Company’s gross unrecognized tax positions:

	December 31,
	2012			2011			2010
Balance as of beginning of year	$	3,936		$	4,128		$	889
Additions based on tax positions related to the current year		400			500			393
Additions based on tax position related to prior year		270			109			2,846
Decreases based on tax positions related to prior year		(4	)		(801	)		—
Balance as of end of year	$	4,602		$	3,936		$	4,128