Efficacy and safety of retatrutide, a GIP, GLP-1, and glucagon receptor agonist, in people with type 2 diabetes and inadequate glycaemic control with diet and exercise (TRANSCEND-T2D-1): a double-blind, randomised, phase 3 trial.

Summary

In a 40-week, multicenter, double-blind phase 3 RCT (n=537), retatrutide monotherapy significantly improved glycemic control and reduced body weight versus placebo in adults with type 2 diabetes inadequately controlled by diet and exercise. Adverse events were consistent with GLP-1 agonist class effects, primarily gastrointestinal.

Key Findings

• 40-week, double-blind, placebo-controlled phase 3 RCT across 48 sites randomized 537 adults to retatrutide 4, 9, or 12 mg or placebo.
• Retatrutide significantly improved glycemic control (HbA1c) and reduced body weight versus placebo.
• Adverse events were consistent with GLP-1 agonists, predominantly gastrointestinal.

Clinical Implications

If approved, retatrutide may offer a potent monotherapy for patients needing both glycemic and weight reduction, with class-typical GI tolerability considerations and need for long-term safety and CV outcome data.

Limitations

• Effect sizes for HbA1c and weight are not detailed in the abstract segment provided
• Duration limited to 40 weeks; long-term safety and cardiovascular outcomes remain unknown

Future Directions

Head-to-head comparisons versus established GLP-1/GIP agents, durability and CV outcome trials, and optimization of dosing/tolerability.