COMET: Comparison of Carvedilol and Metoprolol in Chronic Heart Failure

2003, Carvedilol vs Metoprolol in Heart Failure, The Lancet

The COMET trial randomized 3029 patients with NYHA Class II, III or IV heart failure and a reduced ejection fraction of 35% or less to receive either 25mg of carvedilol twice daily or 50mg of metoprolol twice daily on top of optimal therapy with diuretics and ACE inhibitors unless not tolerated. The co-primary endpoints were all-cause mortality and a composite of all-cause death or all-cause hospitalization.

Patients were followed for 5 years. Overall, 35% of patients assigned to the carvedilol group and 40% in the metoprolol group died (HR:0.83; 95%CI: 0.74 to 0.93; p=0.0017). This reduction in mortality was consistent across all pre-specified subgroups, including: sex, age, NYHA class, LVEF, heart rate, systolic blood pressure, or diabetic status. The co-primary composite endpoint occurred in 75% of patients in the carvedilol group and 74% of those in the metoprolol group (HR: 0.94; 95%CI: 0.86 to 1.02; p=0.122).