Familial hypercholesterolemia carries a markedly increased risk of coronary artery disease. Reduction of plasma low density lipoprotein cholesterol (LDL-C) levels to the normal range may prevent premature atherosclerosis and usually requires a combination of cholesterol-lowering drugs such as 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors plus resins or fibrates. The current, 60-week, open-label investigation involved 22 patients whose plasma LDL-C had not reached the target level for prevention of coronary artery disease in 3 previous studies using fluvastatin alone and in combination with other cholesterol-lowering medications. At the beginning of the current study, patients were stabilized on fluvastatin monotherapy at 40 mg/day. After 6 weeks, the daily treatment changed to a combination of fluvastatin 40 mg/day in the evening and bezafibrate 400 mg/day in the morning. After a further 6 weeks, a lunchtime dose of cholestyramine 8 g/day was added, to form triple cholesterol-lowering therapy. Efficacy was determined by plasma lipid/lipoprotein analysis. Baseline levels were assessed after 4 weeks of placebo treatment, prior to active treatment, in the first fluvastatin study. Safety analyses included liver and renal function tests, creatine phosphokinase levels and blood counts. Compliance was determined by counting the fluvastatin capsules, bezafibrate tablets, and cholestyramine sachets returned by the patients at each visit. The triple-drug combination used in this study was more effective than the double therapy and resulted in stabilization of the LDL-C:high density lipoprotein cholesterol (HDL-C) ratio, at a reduction from baseline ranging from -40.4 to -52.5%.(ABSTRACT TRUNCATED AT 250 WORDS)