Study in Healthy Volunteers to Investigate the Effects of Diltiazem on the Pharmacokinetics of Naloxegol

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 have negative pregnancy test (screening and admission), must not be lactating, and must be of nonchildbearing potential, confirmed at screening by being postmenopausal, or documentation of irreversible surgical sterilization not in. * 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. * Significant orthostatic reaction at enrolment, as judged by the Investigator. * Abnormal vital signs, after 10 minutes supine rest as defined in protocol.