Indobufen in the prevention of thromboembolic complications in patients with heart disease. A randomized, placebo-controlled, double-blind study.

BACKGROUND: The purpose of this randomized, double-blind study was to evaluate the efficacy of indobufen, a reversible inhibitor of platelet cyclooxygenase, in the prevention of embolic events of cardiac origin. METHODS AND RESULTS: One hundred ninety-six patients with heart disease and at risk for cardiogenic embolism (90 with atrial fibrillation and 106 in sinus rhythm) were randomly assigned to receive indobufen (100 mg b.i.d.) or placebo. All patients were reexamined every 3 months for the duration of the study. The primary study end points were cerebral ischemic attack (stroke and transient ischemic attack), systemic embolism, pulmonary embolism, and fatal myocardial infarction. The median duration of treatment was 854 days in the indobufen group and 865 days in the placebo group. The frequencies of primary end points (fatal and nonfatal) were 6.1% and 17.3%, respectively, in the indobufen and placebo groups (p < 0.05) for a reduction of 65% in the risk of a primary event (indobufen/placebo relative risk, 0.35; 95% confidence limits, 0.14-0.89). Adverse drug reactions, mostly gastrointestinal or hemostasis disorders, occurred in 9.2% of indobufen-treated patients. CONCLUSIONS: The results of the study indicate that indobufen may reduce the risk of ischemic events in patients with heart disease associated with an increased risk of embolism.