ABSTRACT
Everolimus is an immunosuppressant intended for use with cyclosporine in acute-rejection prophylaxis following organ transplantation. The possibility of a drug interaction of cyclosporine on everolimus was assessed. In this randomized, two-period, crossover study, 24 healthy subjects received a single oral dose of 2 mg everolimus alone and with one of two cyclosporine formulations: either 175 mg Neoral or 300 mg Sandimmune. The single doses of Neoral and Sandimmune were chosen to yield similar average areas under the concentration-time curve (AUC). Treatments were separated by a 14-day washout period. Cyclosporine AUCs were similar for both formulations (p = 0.53), whereas the peak concentration (Cmax) was significantly higher for Neoral (p = 0.02). Simultaneous administration of Neoral with everolimus increased everolimus Cmax and AUC by 82% and 168%, respectively (p = 0.0001). Coadministration of Sandimmune with everolimus did not affect everolimus Cmax (p = 0.59) but increased everolimus AUC by 74% on average (p = 0.0001). Everolimus elimination half-lives were unchanged in the presence of both cyclosporine formulations. The everolimus AUC increase with Neoral coadministration was significantly greater than the AUC increase with Sandimmune (p = 0.008). However, there was no apparent association between cyclosporine Cmax and the change in everolimus AUC with cyclosporine coadministration. If Neoral or Sandimmune is removed from an everolimus-cyclosporine immunosuppressive regimen, a two- to three-fold decrease in everolimus exposure is expected. Therapeutic monitoring of everolimus concentrations would be helpful after the removal of cyclosporine to individually titrate everolimus exposure.
