A Research Study to Look Into How Semaglutide, Together With a Lower Dose of Insulin Glargine, Compares to a Higher Dose of Insulin Glargine Alone in People With Type 2 Diabetes (SUSTAIN OPTIMIZE)

Inclusion Criteria

• •Diagnosed with Type 2 Diabetes Mellitus (T2D) mellitus greater than or equal to (\>=) 180 days before screening.
• •Glycated haemoglobin (HbA1c) of 7-10 percentage \[(53-86 millimoles per mole (mmol/mol)\] (both inclusive) as assessed by central laboratory on the day of screening.
• •Body mass index (BMI) greater than or equal to (\>=) 25 kilograms per meter square (kg/m\^2) on the day of screening.
• •Stable daily dose(s) greater than or equal to (\>=) 90 days before screening of any of the following anti-diabetic drugs or combination regimens:
• •Any metformin formulations greater than or equal to (\>=) 1500 milligrams (mg) or maximum tolerated or effective dose.
• •Any metformin combination formulation greater than or equal to (\>=) 1500 mg or maximum tolerated or effective dose.
• •The treatment can be with or without sodium glucose cotransporter 2 (SGLT-2) inhibitors.
• •Treated with a once daily basal insulin (e.g. insulin glargine Unit 100 or U300, neutral protamine hagedorn (NPH) insulin, insulin detemir, insulin degludec) less than or equal to (\<=) 40 units/day (U/day) for greater than or equal to (\>=) 90 days before screening. Short-term bolus insulin treatment for a maximum of 14 days before screening is allowed.