The aim of this study was to evaluate the efficacy on LDL-cholesterol (LDL-C) of micronised fenofibrate given for three months at doses ranging from 200 to 400 mg once daily, compared with placebo. A double-blind, randomised, parallel-group, multi-centre trial was performed in four centers of France in 340 hypercholesterolemic patients (163M, 177F) aged 18-75 years. After a 2-3 month single-blind run-in period on placebo and diet, patients with LDL-C greater than or equal to 4.65 mmol/l (180 mg/dl) maintained on the same diet throughout the study were randomly allocated to placebo or to 200, 267, 340 or 400 mg micronised fenofibrate, given once daily with the evening meal for 3 months. LDL-C, total cholesterol (TC), total triglycerides (TG) and apolipoprotein B (Apo B) significantly decreased compared with placebo in all four fenofibrate groups. For all randomised patients, the decrease in the fenofibrate groups ranged from 31.6-38.8% for LDL-C, 24.5-31.9% for TC, 26.7-40.8% for TG, and 27.3-35.0% for Apo B. An increase in HDL-cholesterol of 4.1-8.2% was observed in the fenofibrate groups, but did not reach statistical significance. Lipid values in the placebo group remained unchanged. The therapeutic goal of LDL-C<3.36 mmol/l (130 mg/dl) was reached in 27% in the 200 mg group and increased to 56% in the 300 mg group. There were no major clinical or biological adverse events in the dose interval from 200 mg to 400 mg of micronised fenofibrate per day. This study showed treatment for 3 months with micronised fenofibrate at doses up to 400 mg per day is effective and can reduce LDL-cholesterol up to 30% allowing further evaluation of these doses on longer trials.