Etofibrate is a combination of clofibrate and niacin, used to treat hyperlipemia.

Administering 200 mg/kg of Etofibrate results in significant inhibition of neointimal proliferation of smooth muscle cells in a rabbit model of atherosclerosis, leading to less pronounced plaque expansion. Additionally, 1.2 mM/g of Etofibrate lowers plasma free fatty acid (FFA) levels in male Sprague-Dawley rats. The effect of Etofibrate on plasma glycerol levels varies depending on the dosage and duration of treatment, either increasing or decreasing these levels.

Etofibrate significantly reduces the concentration of cholesterol, triglycerides, free fatty acids, and glycerol, in both total and unesterified forms, in the microsomal fraction of rat liver plasma. It increases the activity of glycerol-3-phosphate dehydrogenase in hepatocytes, which leads to a reduction in the activities of microsomal HMG-CoA reductase and cholesterol 7α-hydroxylase without affecting acyl CoA: cholesterol acyltransferase. Moreover, etofibrate boosts the activity of cytosolic glyceraldehyde-3-phosphate dehydrogenase and the overall concentration of carnitine in rat liver, consequently lowering the concentrations of triglycerides and cholesterol. When fed rats' epididymal adipose tissue is cultured under basal conditions, etofibrate stimulates the rate of fatty acid re-esterification. It reduces the action of lipolytic products in the liver by releasing lipolytic products from adipose tissue and through intrinsic liver metabolism.