A comparison of enteric-coated mycophenolate sodium and mycophenolate mofetil to four years after kidney transplantation: An analysis from the Mycophenolic Acid Observational Renal Transplant Registry

Purpose: Bioavailability of mycophenolic acid (MPA) is higher with concomitant tacrolimus than cyclosporine. This analysis was undertaken to compare MPA dosage and outcomes with enteric-coated mycophenolate sodium (EC-MPS) versus mycophenolate mofetil (MMF) in tacrolimus-treated kidney transplant recipients.  

Methods: The Mycophenolic Acid Observational Renal Transplant (MORE) registry is a prospective, observational study of de novo adult renal transplant patients receiving MPA, managed according to local practice at 40 US sites.

Results: 904 patients (616 EC-MPS, 288 MMF) were followed for up to four years. Baseline characteristics were similar except for living donors (EC-MPS 39%, MMF 49%; p=0.04). More patients received the full recommended dose of MPA (1.44g EC-MPS, 2.0g MMF) with EC-MPS versus MMF at month 1 (79% versus 72%; p=0.02), month 3 (68% versus 57%; p<0.01) and month 6 (53% versus 44%; p=0.03) but proportions were similar thereafter. Mean MPA dose was higher in patients receiving EC-MPS versus MMF patients up to month 6 post-transplant. Efficacy to four years post-transplant was similar with EC-MPS versus MMF: biopsy-proven acute rejection 14% versus 10% (p=0.20), graft survival 93% versus 95% (log rank p=0.52, Kaplan-Meier), and patient survival 96% versus 94% (p=0.28). Mean(SD) serum creatinine was 1.5(1.1)mg/dL with EC-MPS and 1.7(1.8)mg/dL with MMF (p=0.25). Adverse events were similar with EC-MPS or MMF. Gastrointestinal complications were reported in 73% of EC-MPS-treated patients versus 75% of MMF-treated patients (p=0.57).

Conclusion: More kidney transplant patients receiving EC-MPS were maintained on the full recommended MPA dose to month 6 post-transplant than MMF-treated patients, and mean MPA dose during the first six months was correspondingly higher with EC-MPS. Although there were fewer living donor recipients in the EC-MPS group, efficacy was similar with EC-MPS or MMF to 4 years. Safety profiles, including gastrointestinal complications, were similar with EC-MPS or MMF despite higher early MPA dosing with EC-MPS.