Background: Patients with heart failure, a preserved ejection fraction (HFpEF), and obesity have significant disability and suffer frequent exacerbations of heart failure. We hypothesized that tirzepatide, a long-acting agonist of glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptors, would improve a comprehensive suite of clinical endpoints, including measures of health status, functional capacity, quality of life, exercise tolerance, patient well-being, and medication burden in these patients.
Methods: 731 patients in class II-IV heart failure, ejection fraction ≥50%, and body mass index ≥30 kg/m2 were randomized(double-blind) to tirzepatide(titrated up to 15mg subcutaneously weekly)(n=364) or placebo(n=367), added to background therapy for a median of 104 weeks (Q1=66, Q3=126 weeks).
Primary endpoints: tirzepatide reduced the combined risk of cardiovascular death or worsening heart failure and improved Kansas City Cardiomyopathy Questionnaire Clinical Summary Score(KCCQ-CSS). The current expanded analysis included sensitivity analyses of the primary endpoints, 6-minute walk distance(6MWD), EQ-5D-5L health state index, Patient Global Impression of Severity Overall Health(PGIS), NYHA class, use of heart failure medications, and a hierarchical composite based on all-cause death, worsening heart failure, and 52-week changes in KCCQ-CSS and 6MWD.
Results: Patients were aged 65.2±10.7, 53.8%(n=393) were female; BMI 38.2±6.7kg/m2, KCCQ-CSS 53.5±18.5, 6MWD 302.8±81.7meters, and 53%(n=388) had a worsening heart failure event in the prior 12 months. Compared with placebo, tirzepatide produced a consistent beneficial effect across all composites of death and worsening heart failure events, analyzed as time-to-first-event (hazard ratios 0.41-0.67). At 52 weeks, tirzepatide increased KCCQ-CSS 6.9 points (95%CI, 3.3, 10.6, P<0.001), 6MWD 18.3 meters (95%CI, 9.9, 26.7, P<0.001) and EQ-5D-5L 0.06 (95%CI, 0.03, 0.09, P<0.001). The tirzepatide group shifted to a more favorable PGIS (proportional odds ratio 1.99 (95%CI, 1.44, 2.76) and NYHA class (proportional odds ratio 2.26 (95%CI, 1.54, 3.31), both P<0.001 and required less heart failure medications (P=0.015). The broad spectrum of effects was reflected in benefits on the hierarchical composite (win ratio 1.63, 95%CI, 1.17, 2.28;P=0.004).
Conclusions: Tirzepatide produced a comprehensive, meaningful improvement in heart failure across multiple complementary domains; enhanced health status, quality of life, functional capacity, exercise tolerance and well-being; and reduced symptoms and medication burden in patients with HFpEF and obesity.