Eli Lilly's Phase 3 SURMOUNT-1 trial, the longest study of tirzepatide to date, reveals a significant reduction in the risk of type 2 diabetes progression in adults with pre-diabetes and obesity or overweight. The 176-week treatment period demonstrated that weekly tirzepatide injections (5 mg, 10 mg, 15 mg doses) led to a 94% risk reduction compared to placebo.
Sustained Weight Loss and Diabetes Prevention
The study showcased that individuals treated with tirzepatide experienced an average weight loss of up to 22.9% (15 mg dose) which was sustained over the three-year treatment period. Ania Jastreboff, director of the Yale Obesity Research Center, noted that nearly 99% of individuals treated with tirzepatide remained diabetes-free at 176 weeks.
Jeff Emmick, SVP of product development at Eli Lilly, highlighted the clinical significance, stating, "In the SURMOUNT-1 three-year study of tirzepatide, an average weight reduction of up to 22.9% was accompanied by a hazard ratio of 0.06 for progression to type 2 diabetes. This translates to a risk reduction of 94% and a number needed to treat of nine to prevent one case of diabetes."
Impact on Diabetes Diagnosis
Data from the study indicated that at 193 weeks, only 2.4% of patients on tirzepatide were diagnosed with Type 2 diabetes compared to 13.7% of patients in the placebo group, underscoring the drug's potential in preventing the onset of diabetes.
Additional Benefits
Beyond diabetes prevention and weight loss, the study also revealed that tirzepatide treatment was associated with improved glycemic control, cardiometabolic risk factors (including fasting insulin, blood pressure, and lipids), and health-related quality of life, sustained through 176 weeks. A post hoc mediation analysis suggested that approximately half of the observed effect in delaying the onset of type 2 diabetes with tirzepatide was associated with medication-induced weight reduction.
