Low-density lipoprotein cholesterol (LDL-C) is the primary therapeutic target in the National Cholesterol Education Program Adult Treatment Panel III (ATP III) guidelines. This study tested the hypothesis that ezetimibe/simvastatin, a lipid-lowering agent that inhibits both intestinal cholesterol absorption and cholesterol synthesis, provides greater LDL-C reductions than atorvastatin across dose ranges.

This multicenter, double-blind, 6-week parallel-group study randomized 1902 patients with LDL-C above ATP III goal to atorvastatin (10, 20, 40, or 80 mg) or to ezetimibe/simvastatin (10/10, 10/20, 10/40, or 10/80 mg). Patients were stratified by prerandomization LDL-C level.

At each milligram-equivalent statin dose comparison, and averaged across doses, ezetimibe/simvastatin provided greater LDL-C reductions (47%-59%) than atorvastatin (36%-53%). Ezetimibe/simvastatin 10/40 and 10/80 mg also provided significantly greater high-density lipoprotein cholesterol (HDL-C) increases than atorvastatin 40 and 80 mg. Triglyceride reductions were similar for all comparisons. More ezetimibe/simvastatin than atorvastatin patients with coronary heart disease (CHD) or CHD risk equivalents attained the ATP III LDL-C goal of <100 mg/dL and the optional LDL-C target of <70 mg/dL. C-reactive protein reductions were similar between treatment groups. Consecutive elevations in alanine aminotransferase and/or aspartate aminotransferase occurred in significantly more atorvastatin patients than ezetimibe/simvastatin patients. No myopathy or liver-related adverse events led to study discontinuation with either drug.

Ezetimibe/simvastatin was more effective than atorvastatin in lowering LDL-C at each dose comparison and provided greater increases in HDL-C at the 40- and 80-mg statin dose. Ezetimibe/simvastatin is a highly efficacious, well-tolerated treatment option for hypercholesterolemic patients.