A multicenter, double-blind, placebo-controlled study was carried out to evaluate the effect of a new antiplatelet agent, triflusal (2-acetoxy-4-trifluoromethyl benzoic acid), in the prevention of nonfatal myocardial infarction and cardiac or vascular death (principal end-points) in patients with unstable angina. 281 patients were randomly assigned to triflusal (300 mg t.i.d.; n = 143) or placebo (n = 138). After 6 months of treatment, the incidence of nonfatal acute myocardial infarction was significantly lower in the triflusal than in the placebo group: 6 patients (4.2%) versus 17 (12.3%), p = 0.013. The low number of deaths (2/143 triflusal versus 0/138 placebo recipients) hampered statistical analysis of mortality rates. The need for revascularization was similar in the two groups: 24 patients (16.8%) in the triflusal group and 28 (20.3%) in the placebo group, p = 0.449. In conclusion, the results show that treatment with triflusal can reduce the incidence of myocardial infarction in patients with unstable angina.