A Study to Evaluate Effect of AZD6234 as an Adjunct to Incretin-based Therapies in Adult Participants With Obesity or Overweight With Weight-related Comorbidity With or Without Type 2 Diabetes Mellitus

Inclusion Criteria: * Males \& females (inclusive of all gender identities) age ≥18 years * BMI ≥ 30 kg/m2 OR BMI ≥ 27 kg/m2 with at least one of the following weight-related comorbidities (treated or untreated): hypertension, dyslipidaemia, obstructive sleep apnoea, cardiovascular disease, heart failure, chronic kidney disease, metabolic dysfunction associated steatotic liver disease, osteoarthritis of the knee, or stress urinary incontinence * For participants with T2DM only: * Diagnosed with T2DM ≥ 90 days prior to Screening * HbA1c value at Screening of ≥6.0% (42 mmol/mol) and ≤9.0% (75 mmol/mol) managed with diet and exercise alone or with a stable dose of any oral glycaemic-lowering agent and/or incretin-based medication * Receiving a stable dose of incretin- based medications at a dose level that is sufficient for chronic weight management for at least 3 months prior to Screening and Randomisation. * Stable body weight (≤ 3% body weight change) for at least 3 months prior to Randomisation * History of at least one self-reported unsuccessful attempt to lose body weight in their lifetime Exclusion Criteria: * Obesity primarily caused by other endocrine disorders * Type 1 diabetes mellitus * Significant hepatobiliary disease and/or any of the following results at Screening: * ALT ≥ 3.0 × ULN * AST ≥ 3.0 × ULN * TBL \> 1.5 × ULN (except for cases of known Gilbert's Syndrome) * Use of insulin therapy for T2DM within 3 months prior to screening