The main purpose of this study is to investigate efficacy and safety of three doses of petrelintide versus placebo in participants with overweight or obesity and type 2 diabetes.

Main Inclusion Criteria:

• Male or female participants with body mass index (BMI) ≥27.0 kg/m2.
• Diagnosed with type 2 diabetes ≥180 days prior to the day of screening.
• Treated with metformin with or without sodium-glucose cotransporter 2 inhibitors. Treatment should be stable (same drug[s], dose, and dosing frequency) for at least 90 days prior to screening.

Main Exclusion Criteria:

• Severe hypoglycemia within 6 months prior to screening or history of hypoglycemia unawareness.
• Receipt of any other glucose-lowering drug than those listed in the inclusion criterion within 90 days prior to screening.
• A self-reported change in body weight >5% within 90 days prior to screening, irrespective of medical records.
• Treatment with any medication (prescribed or over-the-counter) or alternative remedies (herbal or nutritional supplements) intended to promote weight loss within 90 days prior to screening.
• Previous or planned (during the trial period) obesity treatment with surgery or a body weight loss device. However, liposuction or surgical removal of fat depots more than 1 year prior to screening or device-based interventions (e.g., sleeve, banding, or similar) that have been removed more than 6 months prior to screening, are allowed.
• Obesity due to endocrine disorders or genetic syndromes.