Annual report pursuant to Section 13 and 15(d)

Income Taxes (Tables)

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes and operating loss and credit carryforwards. Significant components of our deferred tax assets are as follows (in thousands):

	December 31,
	2016		2015
Deferred tax assets:
Net operating loss carryforwards	$	87,267	$	91,365
Research credit carryforwards		14,322		13,884
Other, net		2,637		3,417
Deferred revenue		—		—
Total deferred tax assets		104,226		108,666
Valuation allowance		(104,226)		(108,666)
Net deferred tax assets	$	—	$	—

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

The provision for income taxes consists of state minimum taxes due. The effective tax rate of our provision (benefit) for income taxes differs from the federal statutory rate as follows (in thousands):

	Year Ending December 31,
	2016		2015		2014
Computed at 34%	$	1,758	$	(3,840)	$	(839)
State taxes		(187)		(268)		592
Book gains (losses) not currently benefited		(4,439)		2,740		454
Other		659		(20)		235
Revaluation of warrant liability		(280)		1,534		(346)
Research and development credits		(252)		(146)		(97)
Net operating loss carryforward expirations		2,741		—		—
Total	$	—	$	—	$	(1)