Mycophelonic acid inhibits an enzyme which controls the rate of
proliferation of some types of cells, especially T cells. It is a therefore a
potent anti-proliferative, and can be used in place of the older
anti-proliferative
azathioprine. It is usually used as part a combination of
drugs used to suppress the immune system after transplantation.
Mycophenolic acid is available
either in a specially-coated tablet which controls its release, or as mycophenolate
mofetil (MMF) which is converted to mycophenolic acid in the liver.
Compared with azathioprine, it is more lymphocyte-specific, causes less bone
marrow suppression and is associated with fewer opportunistic infections. It may lead to a decreased risk of acute rejection. Mycophenolic acid does cause
gastro-intestinal side effects, however, including severe diarrhoea; sometimes these effects can be reduced by switching from one form of the medication to the other - your doctor will advise you if they think this will help.
The exact role of myoophenolic acid compared with azathioprine has yet to be conclusively
established, but many centres use it in place of azathioprine for high-risk
patients, or patients who have already experienced an episode of acute
rejection. In long-term immunosuppression, it may be used to avoid calcineurin inhibitors or steroids.
