Agents that mimic high density lipoprotein (HDL) are being developed, with the aim of reversing atherosclerosis. Dr Roger Newton (Esperion Therapeutics, US) told the conference that animal studies had indicated that raising HDL might promote regression of atherosclerosis, by mobilising cholesterol from arteries. HDL-mimetic agents could enhance the normal reverse lipid transport system (the transfer of cholesterol from the tissues to the liver for elimination) - Dr Newton called this a type of "molecular angioplasty". Recombinant apolipoprotein (apo) A-1 in a liposome formulation was among the preparations that were being tested as "synthetic HDL particles," he said.