Tirzepatide Research for Type 2 Diabetes

Tirzepatide was first FDA-approved for adult type 2 diabetes in 2022 (as Mounjaro); the US label now includes patients aged 10 years and older. The adult SURPASS program demonstrated HbA1c reductions of 2.0-2.3% at higher studied doses, exceeding semaglutide in SURPASS-2. SURPASS-PEDS enrolled 99 youths and reported a 30-week pooled tirzepatide versus placebo HbA1c difference of -2.28 percentage points (95% CI -2.87 to -1.69); this pediatric result has a different comparator and population. Tirzepatide activates both GIP and GLP-1 receptors; the contribution of each pathway to clinical outcomes cannot be assigned a fixed percentage. SURPASS-2 showed tirzepatide superior to semaglutide for both HbA1c reduction and weight loss. SURPASS-CVOT compared tirzepatide with dulaglutide on major adverse cardiovascular events in 13,299 participants with type 2 diabetes and atherosclerotic cardiovascular disease. It was published in the New England Journal of Medicine on 18 December 2025 (NCT04255433). A primary endpoint event occurred in 801 participants (12.2%) on tirzepatide and 862 (13.1%) on dulaglutide: hazard ratio 0.92, 95.3% CI 0.83 to 1.01. That met the prespecified noninferiority margin of 1.05 (P=0.003) but did not establish superiority (P=0.09).