Comparison of the efficacy of simvastatin and standard fibrate therapy in the treatment of primary hypercholesterolemia and combined hyperlipidemia.

Five multicenter, randomized, double-blind, placebo-controlled studies were conducted in France to compare the efficacy and safety of once-daily simvastatin treatment (10-40 mg/day) with conventional therapy with gemfibrozil 900 mg/day, ciprofibrate 100 mg/day, bezafibrate 400 mg/day, and fenofibrate 300 or 400 mg/day in a total of 800 patients with hypercholesterolemia. Simvastatin was associated with statistically significantly greater (p < or = 0.01) mean percent reductions in plasma low-density lipoprotein (LDL) cholesterol compared with each of the five fibrate regimens, even when administered at its recommended starting dose of 10 mg/day. Furthermore, approximately 90% of patients treated once daily with simvastatin experienced an at least 20% decrease in plasma LDL cholesterol compared with only 36 to 68% of patients treated with the individual fibrate agents (p < or = 0.05). The effectiveness of simvastatin in reducing LDL cholesterol did not differ as a function of the baseline plasma concentrations of total cholesterol or triglycerides. In contrast, the effectiveness of fibrate therapy in lowering plasma LDL cholesterol levels was significantly diminished (p < or = 0.05) among patients with triglyceride concentrations > 1.7 mmol/l. Plasma high-density lipoprotein (HDL) cholesterol levels were increased by approximately 10% after treatment with simvastatin or the fibrates. Although fibrate therapy was more effective overall in lowering plasma triglyceride levels, the effectiveness of simvastatin in reducing plasma triglyceride levels was generally 2- to 4-fold greater in patients with hypercholesterolemia associated with triglyceride levels > or = 2.3 mmol/l than in those with hypercholesterolemia associated with triglyceride levels < 2.3 mmol/l. The results of these studies confirm the superiority of simvastatin to standard fibrate therapy in reducing plasma levels of total and LDL cholesterol. They further indicate that once-daily treatment with simvastatin is effective in patients with isolated hypercholesterolemia or hypercholesterolemia associated with elevated triglyceride levels.