INTANGIBLE ASSETS (Tables)

6 Months Ended

Jun. 30, 2016

INTANGIBLE ASSETS.

Summary of the gross carrying amounts and net book values of our intangible assets

The gross carrying amounts and net book values of our intangible assets were as follows (in thousands):

	June 30, 2016							December 31, 2015
	Remaining	Gross						Gross
	Useful Life	Carrying		Accumulated		Net Book		Carrying		Accumulated		Net Book
Amounts in thousands	(In years)	Amount		Amortization		Value		Amount		Amortization		Value
NUCYNTA product rights	9.0	$	1,019,978	$	(123,836)	$	896,142	$	1,019,978	$	(74,081)	$	945,897
CAMBIA product rights	7.5		51,360		(13,051)		38,309		51,360		(10,483)		40,877
Lazanda product rights	6.1		10,480		(3,396)		7,084		10,480		(2,814)		7,666
Zipsor product rights	5.8		27,250		(13,865)		13,385		27,250		(12,696)		14,554
		$	1,109,068	$	(154,148)	$	954,920	$	1,109,068	$	(100,074)	$	1,008,994

Summary of the future amortization expenses of intangible assets

Based on finite-lived intangible assets recorded as of June 30, 2016, and assuming the underlying assets will not be impaired and that we will not change the expected lives of the assets, future amortization expenses were estimated as follows (in thousands):

	Estimated
	Amortization
Year Ending December 31,	Expense
2016 (remainder)	$	54,073
2017	$	108,147
2018		108,147
2019		108,147
2020		108,147
Thereafter		468,259
Total	$	954,920