Fenofibrate of gemfibrozil for treatment of types IIa and IIb primary hyperlipoproteinemia: a randomized, double-blind, crossover study.

OBJECTIVE: To compare the hypolipidemic effects of gemfibrozil and micronized fenofibrate in patients with primary hyperlipoproteinemia, phenotypes IIa and IIb, with emphasis on their cholesterol-lowering effectiveness.

METHODS: A randomized, double-blind, double-dummy, crossover study was performed to assess the effects of gemfibrozil (900 mg) and micronized fenofibrate (200 mg), administered once daily, to 21 patients (45 to 70 years old)-16 with type IIa and 5 with type IIb primary hyperlipidemia. The two treatment periods lasted 6 weeks each; the run-in and washout periods were 4 weeks.

RESULTS: Both drugs significantly reduced total cholesterol, calculated low-density lipoprotein (LDL) cholesterol, triglycerides, apolipoprotein B, and fibrinogen (P<0.01 for all calculations, except P<0.05 for fibrinogen with gemfibrozil therapy) and increased high-density lipoprotein (HDL) cholesterol (P<0.01). Neither drug affected Lp(a) lipoprotein, whereas uric acid was reduced only by fenofibrate (P<0.01). The percentage decrease in total cholesterol and LDL cholesterol was greater with fenofibrate than with gemfibrozil (-22% versus -15%, P<0.02; and -27% versus -16%, P<0.02, respectively). In contrast, reductions in levels of triglycerides (-54% versus -46.5%), apolipoprotein B, and fibrinogen, as well as the increase in HDL (+9% for both drugs), showed no significant difference between treatments. Separate analysis of patients with type IIb hyperlipoproteinemia showed essentially the same plasma lipid changes as for the overall group, but with greater modifications in triglyceride and HDL concentrations.

CONCLUSION: Fenofibrate and gemfibrozil induced similar variations from baseline values in triglycerides, HDL cholesterol, apolipoprotein B, and fibrinogen, but the decreases in total and LDL cholesterol levels were greater with fenofibrate, in this group of patients with primary hyperlipidemia.