Recommended Dosage and Usage of CellCept (Mycophenolate Mofetil) for Transplant Rejection Prevention
For kidney transplant recipients, mycophenolate mofetil (CellCept) should be used at a dosage of 1g twice daily in combination with a calcineurin inhibitor and corticosteroids as the standard maintenance immunosuppressive regimen to prevent organ rejection. 1, 2
Dosing Recommendations by Transplant Type
Kidney Transplantation
- Initial dose: 1g twice daily (2g total daily dose)
- Administration: Oral tablets, capsules, or suspension
- Timing: Start before or at the time of transplantation
- Combination therapy: Used with tacrolimus (preferred) or cyclosporine, with or without corticosteroids
Heart Transplantation
- Similar dosing to kidney transplantation (1g twice daily)
- Has shown efficacy in preventing rejection and improving survival in heart transplant recipients
Monitoring Requirements
- Blood Levels: Monitor mycophenolate mofetil (MMF) levels regularly 1
- Complete Blood Count: Regular monitoring for potential hematologic effects (leukopenia, anemia, thrombocytopenia)
- Renal Function:
- Daily for first 7 days post-transplant
- 2-3 times weekly for weeks 2-4
- Weekly for months 2-3
- Every 2 weeks for months 4-6
- Monthly for months 7-12
- Every 2-3 months thereafter 1
- Urine Protein: Baseline in first month, every 3 months during first year, then annually 1
Mechanism of Action
Mycophenolate mofetil is a prodrug that is rapidly converted to mycophenolic acid (MPA), which:
- Inhibits inosine monophosphate dehydrogenase (IMPDH), a key enzyme in de novo purine synthesis
- Selectively inhibits lymphocyte proliferation (T and B cells)
- Has more potent inhibitory effects on the type II isoform of IMPDH expressed in activated lymphocytes 2, 3
Common Adverse Effects
- Gastrointestinal: Nausea, vomiting, diarrhea, abdominal cramping (most common side effects)
- Hematologic: Leukopenia, anemia, thrombocytopenia
- Increased infection risk: Particularly viral and bacterial infections
- Pregnancy risks: FDA black box warning due to increased risk of miscarriage and birth defects 2
Important Clinical Considerations
- Generic substitutions should only be used if they meet strict bioequivalence criteria 1
- After switching to a generic medication, monitor blood levels frequently until stable therapeutic targets are achieved 1
- Consider dose reduction by 2-4 months post-transplant if no rejection episodes have occurred 1
- Enteric-coated formulations may improve GI tolerability 2
Drug Interactions
- Decreased MMF levels with:
- Antacids containing magnesium/aluminum
- Cholestyramine
- Rifampin
- Potential for increased toxicity when combined with other immunosuppressants 2
Special Populations
While the evidence provided primarily focuses on adult transplant recipients, pediatric dosing should be adjusted based on body surface area (600-1200 mg/m²) 1.
CellCept has become a cornerstone immunosuppressive agent in transplantation, replacing azathioprine as the preferred antimetabolite due to its superior efficacy in reducing acute rejection episodes in both kidney and heart transplant recipients 2, 4.