What role for metformin in type 1 diabetes?

Tight glycaemic control is key to reducing the risk of cardiovascular and microvascular complications in people with type 1 diabetes. 1 Standard treatment involves optimising insulin therapy to achieve an HbA 1c level of 48mmol/mol (6.5%) or lower. Although not licensed for use in type 1 diabetes, metformin is included in some clinical guidelines as adjuvant therapy for people with type 1 diabetes who are overweight and wish to improve glycaemic control while minimising the dose of insulin. 1,2 The REMOVAL study is the largest trial to date that has investigated the longer-term effects of metformin in people with type 1 diabetes. 3 Here, we consider the role of metformin in individuals with type 1 diabetes in light of these results and other study findings.