Reduced kidney transplant rejection rate and pharmacoeconomic advantage ofmycophenolate mofetil

Background. Several multinational controlled clinical trials have shown tha t triple therapy immunosuppressive regimens which include mycophenolate mof etil (MMF), cyclosporin A (CSA) and steroids (S) are superior compared with conventional regimens which include azathioprine (AZA), CSA and S, mainly because MMF reduces the rate of acute rejection episodes in the first 6 mon ths after kidney transplantation. Post-marketing studies are useful to eval uate the general applicability and costs of MMF-based immunosuppressive reg imens. Methods. Based on the excellent results of the published controlled clinica l trials, we have changed the standard triple therapy immunosuppressive pro tocol (AZA+CSA+S) to an MMF-based regimen (MMF + CSA + S) at our centre. To analyse the impact of this change in regimen, we have monitored 6-month pa tient and graft survival, rejection rate, serum creatinine and CSA levels, as well as the costs of the immunosuppressive and anti-rejection treatments , in 40 consecutive renal transplant recipients (MMF group) and have compar ed the data with 40 consecutive patients transplanted immediately prior to the change in regimen (AZA group). Results. Recipient and donor characteristics were similar in the AZA and MM F groups. Patient survival (37/40; 92.5% in the AZA group err 38/40; 95% in the MMF group), graft survival (36/40 vs 36/40; both 90%) and serum creati nine (137+/-56 vs 139+/-44 mu mol/l) after 6 months were not significantly different. However, the rate of acute rejection episodes (defined as a rise in creatinine without other obvious cause and treated at least with pulse steroids) was significantly reduced with MMF from 60 to 20% (P= 0.0005). Th e resulting cost for rejection treatment was lowered 8-fold (from sFr. 2113 to 259 averaged per patient) and the number of transplant biopsies was low ered > 3-fold in the MMF group. The cost for the immunosuppressive therapy was increased 1.5-fold with MMF (from sFr. 5906 to 9231 per patient for the first 6 months). Conclusions. The change from AZA to MMF resulted in a significant reduction in early rejection episodes, resulting in fewer diagnostic procedures and rehospitalizations. The optimal long-term regimen in terms of patient and p harmacoeconomic benefits remains to be defined.