Open-label Study to Assess the Pharmacokinetics of NKTR-118 in Patients With Impaired Hepatic Function

Inclusion Criteria: * Males or females aged 18 years or more with a weight of at least 50 kg and BMI between 18 and 40 kg/m2, inclusive. * Negative screen for human immunodeficiency virus (HIV) * For subjects with normal hepatic function, negative results for serum hepatitis B (HBV) surface antigen, HCV antibody, and HIV Exclusion Criteria: * Plasma or blood product donation within 1 month of screening or any blood donation/blood loss greater than 500 mL during the 3 months prior to screening. * History of severe allergy/hypersensitivity or ongoing allergy/hypersensitivity * Known or suspected history of drug/chemical abuse within the past 2 years as judged by the Investigator. * Subjects with a history of surgery on the gastrointestinal tract. * For patients with hepatic impairment, fluctuating or rapidly deteriorating hepatic function as indicated by clinical and/or laboratory signs of hepatic impairment (e.g. advanced ascites, infection of ascites, fever, or active gastrointestinal bleeding).