A 55-year-old man with a 5-year history of type 2 diabetes mellitus, prior non-ST elevation myocardial infarction, and stage 3 chronic kidney disease (estimated glomerular filtration rate 45 mL/min/1.73 m², albumin-to-creatinine ratio 35 mg/mmol) is reviewed in a family practice clinic. He takes metformin 1000 mg twice daily, ramipril, and atorvastatin. His HbA1c is 7.9% despite lifestyle measures. According to current Canadian guidelines, which additional antihyperglycaemic agent is most appropriate to add to optimise cardiovascular and renal outcomes?