Lilly: tirzepatide cuts A1C and body weight in two Phase 3 SURPASS trials in type 2 diabetes

Eli Lilly/Tirzepatide (Mounjaro / Zepbound)

Eli Lilly reported Phase 3 results for tirzepatide, a dual GIP/GLP-1 receptor agonist, in type 2 diabetes. At the 15 mg dose, A1C fell 2.37 points in SURPASS-3 (vs insulin degludec) with 12.9 kg weight loss, and 2.59 points in SURPASS-5 (vs placebo) with 10.9 kg weight loss, while comparator groups gained weight.

• Up to 97.4% of tirzepatide recipients achieved A1C below 7%; 62.4% reached non-diabetic levels (below 5.7%).
• In SURPASS-3, insulin users gained 2.3 kg while tirzepatide users lost 12.9 kg; in SURPASS-5, placebo users gained 1.7 kg.
• Gastrointestinal side effects were most common but decreased over time; hypoglycemia rates were lower than comparators.