Mycophenolate mofetil (brand names CellCept, Myfortic) is an immunosuppressant

Immunosuppressant

An immunosuppressant is any substance that performs immunosuppression of the immune system. They may be either exogenous, as immunosuppressive drugs, or endogenous, as ,e. g., testosterone...

 and prodrug

Prodrug

A prodrug is a pharmacological substance administered in an inactive form. Once administered, the prodrug is metabolised in vivo into an active metabolite, a process termed bioactivation. The rationale behind the use of a prodrug is generally for absorption, distribution, metabolism, and...

 of mycophenolic acid

Mycophenolic acid

Mycophenolic acid INN or mycophenolate is an immunosuppressant drug used to prevent rejection in organ transplantation. It inhibits an enzyme needed for the growth of T cells and B cells. It was initially marketed as the prodrug mycophenolate mofetil to improve oral bioavailability. More...

, used extensively in transplant medicine. It is a reversible inhibitor of inosine monophosphate dehydrogenase (IMPDH) in purine

Purine

A purine is a heterocyclic aromatic organic compound, consisting of a pyrimidine ring fused to an imidazole ring. Purines, including substituted purines and their tautomers, are the most widely distributed kind of nitrogen-containing heterocycle in nature....

 biosynthesis

Biosynthesis

Biosynthesis is an enzyme-catalyzed process in cells of living organisms by which substrates are converted to more complex products. The biosynthesis process often consists of several enzymatic steps in which the product of one step is used as substrate in the following step...

, which is necessary for the growth of T cells and B cells. Other cells are able to recover purines via a separate, scavenger, pathway and are thus able to escape the effect.

MMF is a less toxic alternative to azathioprine.

MMF is also used in the treatment of autoimmune diseases, such as Behçet's disease

Behçet's disease

Behçet's disease is a rare immune-mediated systemic vasculitis that often presents with mucous membrane ulceration and ocular involvements...

, pemphigus vulgaris

Pemphigus vulgaris

Pemphigus vulgaris is a chronic blistering skin disease with skin lesions that are rarely pruritic, but which are often painful.-Pathophysiology:...

 and systemic lupus erythematosus

Systemic lupus erythematosus

Systemic lupus erythematosus , often abbreviated to SLE or lupus, is a systemic autoimmune disease that can affect any part of the body. As occurs in other autoimmune diseases, the immune system attacks the body's cells and tissue, resulting in inflammation and tissue damage...

. Suppressing T cells and B cells stops them from attacking healthy cells, but also weakens their ability to defend against infections.

The chemical name for mycophenolate mofetil is 2-morpholinoethyl (E)-6-(1,3-dihydro-4-hydroxy-6-methoxy-7-methyl-3-oxo-5-isobenzofuranyl)-4-methyl-4-hexenoate. Its empirical formula is C₂₃H₃₁NO₇ and molecular weight 433.50. Mycophenolate mofetil is morpholinoethyl ester of mycophenolic acid, which is used to mask the carboxyl group. Mycophenolate mofetil is reported to have pKa values 5.6 for the morpholino moiety and 8.5 for the phenolic group.

Side effects and adverse reactions

Among the most common side-effects of this drug are high blood sugars and increased blood cholesterol levels. Other changes in blood chemistry such as hypomagnesemia

Hypomagnesemia

Hypomagnesemia is an electrolyte disturbance in which there is an abnormally low level of magnesium in the blood. Usually a serum level less than 0.7 mmol/L is used as reference. The prefix hypo- means low . The middle 'magnes' refers to magnesium...

, hypocalcemia, hyperkalemia

Hyperkalemia

Hyperkalemia refers to the condition in which the concentration of the electrolyte potassium in the blood is elevated...

, and an increase in BUN

Bun

A bun is a small, usually sweet, bread. Commonly they are hand-sized or smaller, domed in shape, with a flat bottom. A bun can also be a savory bread roll similar to a bap or barmcake....

 are regularly noted. Coughing and issues with breathing are not uncommon - pleural effusions being noted in approximately 1:3. There is a similar occurrence ratio of Infections; with Leukopenia

Leukopenia

Leukopenia is a decrease in the number of white blood cells found in the blood, which places individuals at increased risk of infection....

 and Anemia

Anemia

Anemia is a decrease in number of red blood cells or less than the normal quantity of hemoglobin in the blood. However, it can include decreased oxygen-binding ability of each hemoglobin molecule due to deformity or lack in numerical development as in some other types of hemoglobin...

 reflecting the immunosuppressive and myelosuppressive nature of the drug. Back and abdominal pain, in addition to headache, nausea, diarrhea, and fever are also experienced with this drug.

More rarely various neoplasia

Neoplasia

Neoplasm is an abnormal mass of tissue as a result of neoplasia. Neoplasia is the abnormal proliferation of cells. The growth of neoplastic cells exceeds and is not coordinated with that of the normal tissues around it. The growth persists in the same excessive manner even after cessation of the...

 occur : Melanoma, Lymphoma, other malignancies having an occurrences of 1 in 20 to 1 in 200 depending on the type. Neoplasia in the skin being the most common site.

Other rarer effects include GI bleeding, and pulmonary fibrosis

Pulmonary fibrosis

Pulmonary fibrosis is the formation or development of excess fibrous connective tissue in the lungs. It is also described as "scarring of the lung".-Symptoms:Symptoms of pulmonary fibrosis are mainly:...

.

Progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy , also known as progressive multifocal leukoencephalitis, is a rare and usually fatal viral disease that is characterized by progressive damage or inflammation of the white matter of the brain at multiple locations .It occurs almost exclusively in...

 is a usually fatal infection of the brain which occurs rarely with this and other immunosuppressive drugs.

Given that this is a pro-drug of mycophenolic acid, the adverse reactions and side-effects noted in that article are also relevant.

Apart from Medscape, the British National Formulary March 2011 was consulted in drafting these side-effects.