Phase 3 trial compares Tirzepatide and Semaglutide efficacy and safety as add-on to metformin in Type 2 Diabetes

Type 2 Diabetes (T2D) is a chronic metabolic disorder characterized by insulin resistance and impaired insulin secretion, leading to hyperglycemia. Despite advancements, many patients struggle to achieve optimal glycemic control with standard therapies like metformin. Glucagon-like peptide-1 receptor (GLP-1R) agonists have revolutionized T2D management by improving glycemic control and offering cardiovascular benefits. Tirzepatide, a novel dual GLP-1R and glucose-dependent insulinotropic polypeptide receptor (GIPR) agonist, represents a new class aiming for potentially superior efficacy by targeting two key incretin pathways, addressing a critical gap in current monotherapy or dual-therapy approaches.

This was a Phase 3, randomized, open-label trial (NCT03987919) enrolling 1879 participants with Type 2 Diabetes already on metformin therapy. Participants were randomized to receive either Tirzepatide at doses of 5 mg, 10 mg, or 15 mg subcutaneously (SC) once weekly, or Semaglutide 1 mg SC once weekly, as an add-on to their existing metformin regimen. The study duration was approximately 47 weeks, with about 12 visits, primarily assessing the effect on blood sugar levels as the main outcome, alongside safety and tolerability profiles.