Recommended Dosage and Usage of Cellcept (Mycophenolate Mofetil) for Transplant Patients
For kidney transplant recipients, mycophenolate mofetil (MMF) should be administered at a dose of 1 g twice daily in combination with a calcineurin inhibitor (preferably tacrolimus) and corticosteroids to prevent organ rejection. 1, 2
Standard Dosing Regimen
- Kidney transplantation: 1 g twice daily (2 g total daily dose)
- Heart transplantation: 1.5 g twice daily (3 g total daily dose)
- Liver transplantation: 1 g twice daily (2 g total daily dose)
Administration Guidelines
- Start MMF before or at the time of transplantation
- Administer orally (available as capsules, tablets, and oral suspension)
- Give on an empty stomach for optimal absorption
- Divide into two daily doses (twice daily administration)
- For patients with GI side effects, consider using the enteric-coated formulation (Myfortic) which delays release until the small intestine 2
Monitoring Requirements
- MMF levels: Regular monitoring is suggested 1
- Complete blood count: Monitor for bone marrow suppression (leukopenia, anemia, thrombocytopenia)
- Renal function: Regular monitoring of serum creatinine and estimated GFR
- Liver function tests: Regular monitoring for hepatotoxicity
- Therapeutic drug monitoring schedule:
- Every other day during immediate post-operative period
- Whenever there is a change in medication or patient status
- When there is a decline in kidney function 1
Dose Adjustments
- Renal impairment: No dose adjustment needed for MMF in renal dysfunction
- Severe GI side effects: Consider dose reduction or temporary interruption
- Neutropenia: If ANC < 1.3 × 10³/μL, consider dose reduction or interruption
- When switching to generic formulations: Monitor drug levels more frequently until stable therapeutic target is achieved 1
Important Considerations
Mechanism of Action
MMF is a prodrug that is rapidly converted to mycophenolic acid (MPA), which selectively inhibits inosine monophosphate dehydrogenase (IMPDH). This enzyme is critical for de novo purine synthesis in T and B lymphocytes, making MMF particularly effective at preventing lymphocyte proliferation and organ rejection 2, 3.
Efficacy
MMF has demonstrated superior efficacy compared to azathioprine in preventing acute rejection in kidney and heart transplant recipients 4, 5. It allows for reduction of calcineurin inhibitor doses, which can improve renal function 2.
Common Side Effects
- Gastrointestinal effects (diarrhea, nausea, vomiting, abdominal pain) in up to 35% of patients
- Hematologic effects (leukopenia, anemia, thrombocytopenia)
- Increased risk of opportunistic infections, particularly CMV 2
Pregnancy Risks
MMF carries significant pregnancy risks including increased risk of miscarriage (49%) and birth defects (23%), prompting an FDA black box warning 2.
Drug Interactions
- Decreased MMF levels with antacids containing magnesium/aluminum
- Decreased MMF levels with cholestyramine and rifampin
- Potential for increased toxicity when combined with other immunosuppressants 2
Combination Therapy
The KDIGO guidelines recommend using MMF as part of a triple immunosuppressive regimen including:
- A calcineurin inhibitor (preferably tacrolimus)
- MMF as the antiproliferative agent
- With or without corticosteroids 1
This combination has shown the best outcomes for preventing organ rejection while minimizing side effects.