Merck/Schering-Plough Pharmaceuticals received FDA approval for Zetia for use, along with diet, in combination with fenofibrate for the reduction of elevated total cholesterol and LDL "bad" cholesterol in patients with mixed hyperlipidemia, when diet alone is not enough. Zetia is the first in a class of cholesterol-lowering agents that inhibits the intestinal absorption of cholesterol.

Fenofibrate is commonly used along with diet to treat hyperlipidemia and has proven efficacy in lowering triglyceride levels and increasing HDL "good" cholesterol. Mixed hyperlipidemia is a metabolic disorder characterized by elevated LDL cholesterol, elevated triglycerides (a form of fat in the bloodstream), and reduced levels of HDL cholesterol.

Approval was based on the results from a trial, which showed that combination therapy of 10 mg of ZETIA co-administered with 160 mg of fenofibrate significantly reduced LDL cholesterol levels when compared to either treatment alone. Patients in a 12-week study showed a 20% reduction in LDL cholesterol levels compared to a 6% reduction in LDL cholesterol levels with 160 mg fenofibrate as monotherapy and a 13% reduction in LDL cholesterol levels with 10 mg ZETIA as monotherapy. In this study, Zetia co-administered with fenofibrate appeared to be well tolerated.