[An inhibitor of intestinal cholesterol transporter]

Ezetimibe is a unique inhibitor of intestinal cholesterol absorption. Ezetimibe selectively inhibits intestinal cholesterol absorption by blocking Niemann-Pick C1-like 1 (NPCIL1). Ezetimibe accelerates VLDL and TG degradation. Therefore, ezetimibe ameliorates postprandial hyperlipidemia. Ezetimibe inhibited the progression of nonalcoholic fatty liver disease (NAFLD) by correcting insulin resistance and decreasing small dense LDL-C in human subjects. In clinical study, ezetimibe administration combined with statin failed to inhibit progression of IMT thickness in ENHANCE (Ezetimibe and Simvastatin in Hypercholesterolemia Enhances Atherosclerosis Regression) study. In this study baseline IMT thickness (0.7 mm) of patients was within normal range. Therefore only two years observation was too short to demonstrate anti-atherogenic effects of ezetimibe. SEAS(Simvastatin and Ezetimibe in Aortic Stenosis) trial examined effects of combination therapy with ezetimibe and statin in patients with aortic stenosis. Combination therapy could not inhibit progression of aortic stenosis. However, events of ischemic heart disease, especially CABG were significantly decreased only in combination group. Statin was not reported to reduce CVD(cardiovascular disease) in moderate to severe CKD patients. In SHARP(Study of Heart and Renal Protection) study, patients with severe renal disease were allocated either for statin alone group or combination therapy group with statin and ezetimibe. Combination therapy significantly decreased non-hemorrhagic stroke by 25 % compared with statin alone group in severe CKD and HD(hemodialysis) patients. Ezetimibe has unique lipid lowering profile increasing HDL-C concomitant with decreasing LDL-C and TG. Ezetimibe should be initiated first in patients with insulin resistant metabolic syndrome. Ezetimibe should be combined with statin to reduce not only LDL-C but RLP-C(remnant like lipoprotein particle choletserol) in type IIb dyslipidemia.