Atorvastatin (INN) (Lipitor, Pfizer), is a member of the drug class known as statins, used for lowering blood cholesterol. It also stabilizes plaque and prevents strokes through anti-inflammatory and other mechanisms. Atorvastatin inhibits HMG-CoA reductase, the rate-determining enzyme located in hepatic tissue that produces mevalonate, a small molecule used in the synthesis of cholesterol and other mevalonate derivatives. This lowers the amount of cholesterol produced which in turn lowers the total amount of LDL cholesterol. Atorvastatin was first synthesized in 1985 by Bruce Roth while working at Parke-Davis Warner-Lambert Company (now Pfizer). With 2006 sales of US$12.9 billion, Lipitor is the largest-selling drug in the world.