Accrued Liabilities

3 Months Ended

Mar. 31, 2014

7. Accrued Liabilities

Accrued liabilities are comprised of the following (and are included within the accounts payable and accrued expenses line item on the consolidated balance sheets), in thousands:

	March 31,		December 31,
	2014		2013
	(unaudited)

Accrued clinical trial and clinical supply costs	$	538	$	2,253
Accrued compensation	3,829		5,016
Accrued rebates and allowances	2,817		1,903
Accrued product costs	517		2,503
Accrued sales and marketing expenses	1,540		1,077
Accrued interest	1,251		619
Other accrued liabilities	1,998		1,801
	$	12,490	$	15,172

Accrued clinical trial and clinical supply costs consist primarily of investigator fees, contract research organization services, contract manufacturing, pass-through costs and laboratory costs. Other accrued liabilities consist primarily of professional fees, distribution fees, and miscellaneous accrued expenses.