The purpose of this study is to find out if zenagamtide is safe and effective for treating participants who have excess body weight compared to treatment with semaglutide.
Male or female (sex at birth).
Age 18 years or above at the time of signing the informed consent.
Glycated haemoglobin (HbA1c) ≥ 6.5% (48 millimoles per mole [mmol/mol]) as measured by the central laboratory at screening.
History of type 1 or type 2 diabetes mellitus as declared by the participant or reported in the medical records.
Treatment with glucagon-like-peptide-1 (GLP-1) receptor agonists (RA), dual GLP-1/gastric inhibitory peptide (GIP) RAs (or any other GLP-1 based treatment) or amylin analogues within 1 year before screening.