Mycophenolate Mofetil

Pharmacology: Mechanism of Action: The active substance in mycophenolate mofetil, is an immunosuppressive medicine. In the body, it is converted into mycophenolic acid, which blocks an enzyme called 'inosine monophosphate dehydrogenase'. This enzyme is important for the formation of DNA in cells, particularly in the lymphocytes (a type of white blood cell which is involved in the rejection of organ transplants). By preventing the production of new DNA, Mycophenolate mofetil reduces the rate at which the lymphocytes multiply. This makes the transplanted organ, lowering the risk of the organ being rejected.Pharmacokinetics: Following oral administration, mycophenolate mofetil undergoes rapid and extensive absorption and complete presystemic metabolism to the active metabolite, MPA. Mycophenolate mofetil is not measurable systemically in plasma following oral administration. MPA at clinically relevant concentrations, is 97% bound to plasma albumin. MPA is metabolized principally by glucuronyl transferase to form the phenolic glucuronide of MPA (MPAG), which is not pharmacologically active. A negligible amount of substance excreted as MPA (<1% of dose) in the urine. Orally administered radiolabelled mycophenolate mofetil results in complete recovery of the administered dose with 93% of the administered dose recovered in the urine and 6% recovered in the feces. Most (about 87%) of the administered dose is excreted the urine as MPAG.