Introduction
Myfortic Tablet (Delayed Release) 360 mg is an an immunosuppresant drug and potent anti-proliferative, and can be used in place of the older anti-proliferative azathioprine. It is usually used as part of triple therapy including a calcineurin inhibitor (ciclosporin or tacrolimus) and prednisolone. It is also useful in research for the selection of animal cells that express the E. coli gene coding for XGPRT (xanthine guanine phosphoribosyltransferase).
Uses
Myfortic Tablet (Delayed Release) 360 mg is an immunosuppressant used to prevent organ transplant rejections.
For the prophylaxis of organ rejection in patients receiving allogeneic renal transplants, administered in combination with cyclosporine and corticosteroids.
Associated Conditions
Pharmacodynamics
Myfortic Tablet (Delayed Release) 360 mg is an antibiotic substance derived from Penicillium stoloniferum. It blocks de novo biosynthesis of purine nucleotides by inhibition of the enzyme inosine monophosphate dehydrogenase. Myfortic Tablet (Delayed Release) 360 mg is important because of its selective effects on the immune system. It prevents the proliferation of T-cells, lymphocytes, and the formation of antibodies from B-cells. It also may inhibit recruitment of leukocytes to inflammatory sites.
Mechanism of Action
Myfortic Tablet (Delayed Release) 360 mg is a potent, selective, uncompetitive, and reversible inhibitor of inosine monophosphate dehydrogenase (IMPDH), and therefore inhibits the de novo pathway of guanosine nucleotide synthesis without incorporation into DNA. Because T- and B-lymphocytes are critically dependent for their proliferation on de novo synthesis of purines, whereas other cell types can utilize salvage pathways, mycophenolic acid has potent cytostatic effects on lymphocytes. Myfortic Tablet (Delayed Release) 360 mg inhibits proliferative responses of T- and B-lymphocytes to both mitogenic and allospecific stimulation. Addition of guanosine or deoxyguanosine reverses the cytostatic effects of mycophenolic acid on lymphocytes. Myfortic Tablet (Delayed Release) 360 mg also suppresses antibody formation by B-lymphocytes. Myfortic Tablet (Delayed Release) 360 mg prevents the glycosylation of lymphocyte and monocyte glycoproteins that are involved in intercellular adhesion to endothelial cells and may inhibit recruitment of leukocytes into sites of inflammation and graft rejection.
Absorption
Bioavailability following oral administration of Myfortic delayed-release tablet ranges from 70-95%
Volume of Distribution
- 54 ± 25 L
Protein Binding
>98%
Half Life
The mean elimination half-life for mycophenolic acid ranges from 8-16 hours, while that of the MPAG metabolite ranges from 13-17 hours.
Clearance
- 140 +/- 30 mL/min [Stable renal transplant patients]
Toxicity
Oral (LD50): Acute: 352 mg/kg [Rat], 1000 mg/kg [Mouse], and >6000 mg/kg Rabbit. Possible signs and symptoms of acute overdose could include the following: hematological abnormalities such as leukopenia and neutropenia, and gastrointestinal symptoms such as abdominal pain, diarrhea, nausea and vomiting, and dyspepsia.
Food Interactions
- Take on an empty stomach. Take mycophenolic acid at least 1 hour before or 2 hours after eating.
Dosage
Dosage in pediatric kidney transplant patients: The recommended dose of Myfortic Tablet (Delayed Release) 360 mg in conversion (at least 6 months post-transplant) pediatric patients age 5 years and older is 400 mg/m2 body surface area (BSA) administered twice daily (up to a maximum dose of 720 mg administered twice daily). Pediatric patients with a BSA of 1.19 to 1.58 m2 may be dosed either with three Myfortic Tablet (Delayed Release) 360 mg 180 mg tablets, or one 180 mg tablet plus one 360 mg tablet twice daily (1080 mg daily dose). Patients with a BSA of >1.58 m2 may be dosed either with four Myfortic Tablet (Delayed Release) 360 mg 180 mg tablets, or two Myfortic Tablet (Delayed Release) 360 mg 360 mg tablets twice daily (1440 mg daily dose).
Myfortic Tablet (Delayed Release) 360 mg tablets should be taken on an empty stomach, 1 hour before or 2 hours after food intake. Tablets should not be crushed, chewed, or cut prior to ingesting. The tablets should be swallowed whole in order to maintain the integrity of the enteric coating.
