Efficacy and Safety of KAI-9531 Administered Once Weekly in Participants Living With Obesity or Overweight and Diabetes

Key Inclusion Criteria: * Diagnosis of type 2 diabetes mellitus (T2DM). * Receiving stable therapy for T2DM for 3 months prior to Screening. This includes diet/exercise alone and any oral medication for T2DM treatment except for glucagon-like peptide-1 receptor (GLP-1R) agonist, GLP-1R/glucose-dependent insulinotropic polypeptide receptor (GIPR) dual agonist, or dipeptidyl peptidase-4 (DPP-4) inhibitors. * BMI ≥27 kg/m\^2. * History of at least 1 self-reported unsuccessful effort to lose weight with diet and exercise within the prior 6 months. Key Exclusion Criteria: * Current diagnosis or history of type 1 diabetes mellitus (T1DM) or any other type of diabetes except T2DM. * History of diabetic ketoacidosis or hyperosmolar state/coma within 1 year prior to Screening. * History of severe hypoglycemia or hypoglycemia unawareness within 1 year prior to Screening. * Started medications within 3 months prior to Screening that may cause significant weight gain, including, but not limited to, tricyclic antidepressants, atypical antipsychotics, and mood stabilizers. * Unstable weight defined as self-reported change in body weight exceeding 5% within 3 months prior to Screening. * Family or personal history of multiple endocrine neoplasia Type 2 or medullary thyroid cancer. * Uncontrolled hypertension or unstable cardiovascular disease. * History of chronic or acute pancreatitis. * Known clinically significant gastric emptying abnormality or chronic treatment with medications that…