Tirzepatide succeeds in Phase 3 SUMMIT in heart failure with preserved ejection fraction and obesity

Eli Lilly/Tirzepatide (Mounjaro / Zepbound)

In the 731-patient SUMMIT trial, tirzepatide cut the risk of heart-failure urgent visits, hospitalisation, intensified diuretics or cardiovascular death by 38% versus placebo in people with obesity and heart failure with preserved ejection fraction (stiff heart, normal ejection). Patients lost 15.7% body weight and reported better symptoms.

• HFpEF is a stiff-heart condition where weight loss and reduced afterload can improve outcomes; tirzepatide showed a 38% reduction in composite events.
• Weight loss was 15.7% on tirzepatide versus 2.2% on placebo (efficacy estimand).
• Kansas City Cardiomyopathy Questionnaire improvement favored tirzepatide, indicating symptom relief.
• Safety profile aligned with previous tirzepatide trials; gastrointestinal side effects were most common.