Cyclosporine A and tacrolimus combined with enteric-coated mycophenolate sodium influence the plasma mycophenolic acid concentration - a randomised controlled trial in Chinese live related donor kidney transplant recipients

How cyclosporin reduces mycophenolic acid exposure by 40% while other calcineurin inhibitors do not

The most frequently used immunosuppressive treatment in kidney transplant recipients is the combination therapy of a calcineurin inhibitor and mycophenolate mofetil (MMF), with or without corticosteroids. Cyclosporin and tacrolimus are the two calcineurin inhibitors registered for this indication. Also in the treatment of glomerular diseases calcineurin inhibitors and mycophenolic acid are being used on a worldwide scale, either alone or as combined treatment. In January 2021 the U.S. Food and Drug Administration (FDA) has approved voclosporin, a novel calcineurin inhibitor for the treatment of adult patients with active lupus nephritis. There is a clinically relevant drug-drug interaction between cyclosporin and mycophenolate. As a result of cyclosporin-induced inhibition of the enterohepatic recirculation of mycophenolate, the mycophenolic acid-AUC is significantly lower (40%) in case of cyclosporin co-administration as compared to cotreatment with either tacrolimus or voclosporin (or no CNI co-treatment). The aim of this mini review is to summarize this potential drug-drug interaction and explain how cyclosporin affects the pharmacokinetics of mycophenolate. The optimal dose of MMF is likely to depend on the calcineurin inhibitor with which it is co-administered. Furthermore clinical implications are discussed, including the potential emergence of mycophenolic acid (MPA)-related side effects after discontinuation of cyclosporin co-treatment.

Pharmacokinetics of mycophenolic acid after haplo-hematopoietic stem cell transplantation in Japanese recipients

PURPOSE

Mycophenolate mofetil (MMF), a mycophenolic acid (MPA) prodrug, is used to prevent graft-versus-host disease (GVHD) in hematopoietic stem cell transplantation (HSCT). Although previous studies have reported that enterohepatic circulation (EHC) of MPA, which is usually observed in MMF-treated patients, does not occur in HSCT patients, it is unclear what happens in haploidentical-HSCT (haplo-HSCT) patients, who are using post-transplant cyclophosphamide. This study was conducted to investigate MPA pharmacokinetics in haplo-HSCT patients.

METHODS

Seventeen haplo-HSCT patients, who received MMF for GVHD prophylaxis, were enrolled in this study. We collected blood samples on days 14 and 28, and plasma MPA concentrations were measured by high-performance liquid chromatography; pharmacokinetic parameters such as area under the curve (AUC), mean residence time (MRT), and apparent oral clearance (CL/F) were measured with moment analysis. We also evaluated EHC as AUC_6-12h/AUC_0-12h.

RESULTS

There was no significant difference in MPA pharmacokinetic parameters between days 14 and 28. There was also no difference between the pharmacokinetic parameter changes and diarrhea. Additionally, varying plasma MPA concentrations suggested that MPA EHC did not occur.

CONCLUSION

In this study, we revealed the pharmacokinetics of MMF in Japanese haplo-HSCT recipients. Additionally, our study demonstrated that MPA EHC might not occur in Japanese haplo-HSCT recipients.

Tacrolimus in preventing transplant rejection in Chinese patients--optimizing use

Tacrolimus is a product of fermentation of Streptomyces, and belongs to the family of calcineurin inhibitors. It is a widely used immunosuppressive drug for preventing solid-organ transplant rejection. Compared to cyclosporine, tacrolimus has greater immunosuppressive potency and a lower incidence of side effects. It has been accepted as first-line treatment after liver and kidney transplantation. Tacrolimus has specific features in Chinese transplant patients; its in vivo pharmacokinetics, treatment regimen, dose and administration, and adverse-effect profile are influenced by multiple factors, such as genetics and the spectrum of primary diseases in the Chinese population. We reviewed the clinical experience of tacrolimus use in Chinese liver- and kidney-transplant patients, including the pharmacology of tacrolimus, the immunosuppressive effects of tacrolimus versus cyclosporine, effects of different factors on tacrolimus metabolism on Chinese patients, personalized medicine, clinical safety profile, and patient satisfaction and adherence. This article provides guidance for the rational and efficient use of tacrolimus in Chinese organ-transplant patients.