This study will evaluate the effect of various degrees of renal function on the pharmacokinetics and safety of ALKS 5461.

Inclusion Criteria:

For all subjects:

• Has a body mass index (BMI) of 18.0-40.0 kg/m^2 and a total body weight >50kg
• Agrees to use an approved method of contraception for the duration of the study
• Additional criteria may apply

For subjects with renal impairment:

• Has severe or end stage renal disease, and does not require dialysis
• Has stable renal function for at least 60 days preceding screening
• Additional criteria may apply

Exclusion Criteria:

For all subjects:

• Has any past history or current finding of a clinically significant observed abnormality, psychiatric or medical condition other than renal impairment
• Has a history of gastrointestinal surgery affecting drug absorption or biliary elimination, excluding appendectomy or cholecystectomy
• Is pregnant, planning to become pregnant, or lactating
• Has a history of clinically significant allergy or a hypersensitivity to opioids
• Additional criteria my apply

For subjects with renal impairment:

• Has evidence of compromised respiratory function, seizure disorder, or myasthenia gravis
• Has received a kidney transplant
• Additional criteria may apply