SURMOUNT-5 Head-to-Head: Tirzepatide Delivers 21.6% Weight Loss vs Semaglutide's 15.4%
The first definitive Phase 3B head-to-head trial of Lilly's tirzepatide versus Novo Nordisk's semaglutide in 750 patients with obesity over 72 weeks showed tirzepatide produced 21.6% mean weight loss vs semaglutide's 15.4%. 36.2% of tirzepatide patients achieved ≥25% weight loss vs 19.4% on semaglutide. Results published April 20 give Lilly a clear comparative data point in the GLP-1 market share battle.