A 52-year-old man with known type 2 diabetes is reviewed in clinic. His latest HbA1c is 68 mmol/mol despite lifestyle modifications and metformin 1g BD. His eGFR is >60 mL/min/1.73m² and BMI is 31 kg/m². He has no history of cardiovascular disease. According to NICE NG28, what is an appropriate next agent to add?