INS and type 2 diabetes mellitus: The United Kingdom Prospective Diabetes Study (UKPDS) group performed a major randomized controlled trial evaluating the effect of metformin and intensive antihyperglycemic therapy (insulin, glibenclamide, or chlorpropamide) compared with conventional glucose-lowering therapy in 5,102 patients.2 Patients receiving metformin had a significant reduction in all T2DM-related events compared with those receiving conventional therapy (relative risk reduction [RRR] 32%; hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.53-0.87) and the intensive glycemic control group.