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. Standard treatment involves optimising insulin therapy to achieve an HbA 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. The REMOVAL study is the largest trial to date that has investigated the longer-term effects of metformin in people with type 1 diabetes. Here, we consider the role of metformin in individuals with type 1 diabetes in light of these results and other study findings.