Drug-Drug Interaction and Safety of AZD4041 Study (Part 1) and Efficacy, Safety, Pharmacokinetics and Pharmacodynamics of AZD4041 Study in Opioid Use Disorder (Part 2).

Inclusion Criteria: • Male participants: * with female partner(s) of childbearing potential (including breastfeeding partner) must be willing to use a reliable method of contraception throughout the study period for 30 days) after final investigational medicinal product (IMP) administration for Part 1a, and for 5 drug elimination half-lives after final IMP administration for Part 1b and Part 2. * must not donate sperm starting at screening and throughout the study period and for 30 days) after final IMP administration for Part 1a and for 5 drug elimination half-lives after final IMP administration for Part 1b and Part 2. * with pregnant partner(s) must agree to remain abstinent or use a condom for the duration of the pregnancy throughout the study period and for 5 drug elimination half-lives after final IMP administration. Part 1 * Body mass index (BMI) within 18.0 kg/m2 to 30.0 kg/m2, inclusive. * Body weight of within 50 kg to 100 kg, inclusive. * Non- or ex-smoker (an ex-smoker is defined as someone who completely stopped using nicotine products for at least 180 days prior to the first drug administration). Part 2 * BMI within the range of ≥ 18 and ≤ 35 kg/m2 at the screening visit. * Participant has a diagnosis of moderate to severe OUD according to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) using the Mini International Neuropsychiatric Interview (MINI) version 7.02. * Participant is voluntarily seeking treatment for OUD. * Partic…