Myfortic (Mycophenolic Acid) Uses in Transplantation
Myfortic (mycophenolic acid) is primarily used as an immunosuppressant for prophylaxis of organ rejection in kidney transplant recipients, in combination with cyclosporine and corticosteroids. 1
Primary Indications
- FDA-approved uses:
- Prevention of organ rejection in adult kidney transplant recipients
- Prevention of organ rejection in pediatric kidney transplant patients at least 5 years of age and older who are at least 6 months post-transplant 1
Mechanism of Action
Mycophenolic acid (MPA) functions as an immunosuppressant through:
- Selective inhibition of inosine monophosphate dehydrogenase (IMPDH)
- Blocking purine synthesis
- Inhibiting T and B lymphocyte proliferation 2
- Preventing acute and chronic allograft rejection 3
Formulation Differences
Myfortic is available as an enteric-coated formulation of mycophenolic acid sodium (EC-MPS), which:
- Was developed to reduce gastrointestinal side effects compared to mycophenolate mofetil (MMF) 4
- Delays MPA release until the small intestine 5
- Is available as 180 mg and 360 mg delayed-release tablets 1
Important note: Myfortic (EC-MPS) and mycophenolate mofetil (MMF) should not be used interchangeably due to different absorption profiles 1
Clinical Use in Transplantation
Myfortic is typically used:
- In combination therapy with calcineurin inhibitors (cyclosporine or tacrolimus) and corticosteroids 2, 1
- As a replacement for azathioprine in immunosuppressive regimens 5
- At a standard adult dose of 720 mg twice daily (1,440 mg total daily dose) 1
- On an empty stomach, 1 hour before or 2 hours after food intake 1
Efficacy in Transplantation
- Multiple studies have demonstrated that Myfortic is as effective as mycophenolate mofetil in preventing renal graft rejection 4
- In Korean de novo renal transplant patients, Myfortic with tacrolimus showed an incidence of biopsy-confirmed acute rejection of only 10.8% within 6 months after transplantation 6
- Long-term studies (up to 3 years) have shown good efficacy and tolerability of EC-MPS in renal transplant recipients 7
Important Safety Considerations
Myfortic carries several significant warnings:
- Embryo-fetal toxicity: Associated with increased risks of pregnancy loss and congenital malformations 1
- Malignancy risk: Increased risk of lymphoma and other malignancies, particularly skin cancers 1
- Infection risk: Increased susceptibility to bacterial, viral, fungal, and protozoal infections 1
- Blood dyscrasias: Monitor for neutropenia or anemia 1
- Gastrointestinal complications: Use with caution in patients with active digestive system disease 1
Drug Interactions
Important interactions to monitor:
- Antacids with magnesium and aluminum hydroxides decrease MPA concentrations 1
- Cholestyramine and other drugs that interfere with enterohepatic recirculation may decrease MPA concentrations 1
- Concurrent use with azathioprine is not recommended due to competition for purine metabolism 1
- May reduce effectiveness of hormonal contraceptives 1
Monitoring Requirements
Patients on Myfortic should be monitored for:
- Signs of organ rejection
- Complete blood count with differential
- Renal and hepatic function
- Opportunistic infections
- Gastrointestinal side effects 2, 1
Myfortic represents an important component of immunosuppressive regimens in transplantation medicine, with particular utility in kidney transplant recipients who may experience gastrointestinal intolerance to mycophenolate mofetil.