CETP (Cholesteryl Ester Transfer Protein): CETP is a protein that plays a key role in lipid metabolism by facilitating the transfer of cholesteryl esters and triglycerides between lipoproteins. It influences the composition of HDL (high-density lipoprotein) and LDL (low-density lipoprotein), making it important in cardiovascular health. CETP inhibitors have been studied as potential treatments for atherosclerosis because of their ability to increase HDL cholesterol levels.