A Study to Evaluate Effect of AZD6234 in Adult Participants With Type 2 Diabetes Mellitus and Obesity or Overweight

Inclusion Criteria: * Males \& females (inclusive of all gender identities) age ≥18 years * BMI ≥27 kg/m2 * Diagnosed with T2DM ≥90 days prior to Screening * HbA1c value at Screening of ≥6.0% (42 mmol/mol) and ≤10% (86 mmol/mol) managed with diet and exercise alone or with a stable dose of any oral glycaemic-lowering agent (as per local labelling) * Stable body weight (≤5% 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 lifetime Exclusion Criteria: * Obesity primarily caused by other endocrine disorders * Type 1 diabetes mellitus (or any other diabetes mellitus that is not clearly Type 2 diabetes), OR have history of ketoacidosis or hyperosmolar coma/state within 3 months prior to Screening * Significant hepatobiliary disease and/or any of the following results at Screening: * ALT ≥ 3.0 X ULN * AST ≥ 3.0 X ULN * TBL \> 1.5 X ULN (except for cases of known Gilbert's Syndrome) * Has received treatment with a GLP-1 receptor agonist or GLP-1 containing medication for any indication within 3 months before Randomisation * Use of insulin therapy for T2DM within 3 months prior to screening