A Study to Evaluate the Safety and Efficacy of JNJ-64565111 in Severely Obese Participants With Type 2 Diabetes Mellitus

Inclusion criteria

• Body Mass Index (BMI) greater than or equal to (>=) 35 to less than or equal to (<=) 50 kilogram per meter square (kg/m^2) at screening
• Stable weight (that is, change of <= 5 percent [%] within 12 weeks before screening based on medical or participant reported history)
• Hemoglobin A1c of >= 6.5% and <= 9.5% at screening and meets one of the inclusion criteria as: (a) on diet and exercise alone >= 12 weeks prior to screening; (b) on stable dose of single oral antihyperglycemic agent (AHA) or dual-combination oral AHAs for >= 12 weeks prior to screening
• Women must be either: (a) Postmenopausal, or (b) Permanently sterilized or otherwise be incapable of pregnancy, or (c) Heterosexually active and practicing a highly effective method of birth control, or (d) Not heterosexually active
• Willing and able to adhere to specific the prohibitions and restrictions

Exclusion criteria

• History of obesity with a known secondary cause (example, Cushing's disease/syndrome)
• History of Type 1 diabetes mellitus, diabetic ketoacidosis, pancreas or beta-cell transplantation, or diabetes secondary to pancreatitis or pancreatectomy
• Fasting C-peptide less than (<) 0.7 nanogram per milliliter (ng/mL) at screening
• Fasting fingerstick glucose of >= 270 milligram per deciliter (mg/dL) (>=15 millimoles per liter [mmol/L]) on Day 1
• Ongoing, inadequately controlled thyroid disorder as assessed by the investigator's review of the participant's medical history. Participants taking thyroid hormone replacement therapy must be on stable doses for at least 6 weeks before the screening visit