Ezetimibe reduces plasma plant sterol levels in mice lacking ABCG5/G8 and patients with homozygous phytosterolemia and can improve phytosterolemia-related adverse conditions, but the levels remain substantially above the normal range [27, 32]; at an average of ~50% of pretreatment levels in the patients even with years of the treatment with the drug [33, 34]. Here, ABCG5 is linked to sitosterolemia.