Study in Healthy Volunteers to Investigate the Effects of Quinidine on the Pharmacokinetics of NKTR-118

Inclusion Criteria: * Provision of signed and dated, written informed consent prior to any study-specific procedures. * Male and female (nonchildbearing potential, nonlactating) healthy volunteers aged 18 to 55 years inclusive, with suitable veins for cannulation or repeated venipuncture. * Female volunteers must be nonpregnant and nonlactating. Women of childbearing potential must have negative pregnancy test (screening and admission) and be using a highly-effective form of birth control for 3 months before enrollment. * Male volunteers should be willing to use barrier contraception ie, condoms, from the first day of dosing until 3 months after dosing with the IP. The female partner should use contraception during this period. * Volunteers must have a BMI between 18 and 30 kg/m2, inclusive, and weigh at least 50 kg. Exclusion Criteria: * Any clinically significant disease or disorder (eg, cardiovascular, pulmonary, gastrointestinal, liver, renal, neurological, musculoskeletal, endocrine) which, may put the volunteer at risk of participation in the study, or influence of the ADME of drugs. * Any clinically significant illness, medical/surgical procedure or trauma within 4 weeks of the first administration of IP. * Any clinically significant abnormalities in clinical chemistry, hematology, or urinalysis results as judged by the Investigator. * History (personal or family) of torsades de pointes, any other polymorphic ventricular tachycardia, long QT syndrome, sudden death or Brugada syndrome, or personal history of sustained (greater than 30 s) monomorphic ventricular tachycardia. * Abnormal vital signs, after 10 minutes supine rest as defined in protocol.