The FDA approved the treatment known as lomitapide for use in patents with a rare genetic disease that causes extreme elevation of blood cholesterol levels. The once-daily pill it calls Juxtapid is Aegerion Pharmaceuticals' (AEGR) 1st drug on the market. It's approved to treat a potentially fatal condition that causes abnormalities in liver cells responsible for clearing " bad" cholesterol. But the drug will carry a boxed warning alerting users to the risk of liver toxicity. Shares fell 1.8% to 25.25.