Effect of Systematic Conversion to Generic Mycophenolate Mofetil (MMF) in Kidney Transplantation: A Single-Center Clinical Experience from Japan

Abstract

IntroductionRecently, more and more generic drugs have been used for immunosuppressive drugs in the field of organ transplantation. Some reports have indicated that blood concentration of most generic drugs is difficult to maintain stability, and it may cause the difference in graft survival of transplanted organs between original drugs and generic drugs. In this article, we report the cases could not maintain blood concentration of generic drugs of mycophenolate mofetil (MMF). ResultsIn 4 cases out of 5 cases that we had to change original MMF to generic MMF, there were cases that blood concentration level was not stabilized. There were possibility that the lowered blood concentration level of MMF caused a rejection, in two cases. Mean MMF trough level was decreased from 3.6 ± 1.9 μg/mL to 0.6 ± 0.4 μg/mL. Due to the early detection, it did not become severe or failure of graft function, however, we cannot deny the possibilities that side effects were increased and rejection rose. In these cases, we discontinued to use the generic drugs thereafter due to unstable plasma concentration of MMF. DiscussionSome reports have indicated that failure to maintain plasma concentration of MMF leads to rejection. Therefore, maintenance of effective plasma concentration and prevention of rejection are essential to long-term graft survival in kidney transplant. ConclusionGeneric drug formulations may exhibit differences in effects and absorption compared to the brand-name drug. If the generic drug should be used, patients should be closely monitored.