Risks associated with conversion of stable patients after liver transplantation to the microemulsion formulation of cyclosporine

Background. Neoral is a microemulsion formulation of cyclosporine that has a better pharmacokinetic profile than the standard formulation (Sandimmune). To prove the safety of converting stable liver transplant patients from Sandimmune to Neoral, we conducted a prospective trial involving 54 patients. Method. The average time from transplantation to conversion was 48.5±21.6 months. Thirty of 54 patients (55%) required a dose reduction during the study for various reasons. Five of 30 patients had the first dose reduction because of increased levels of cyclosporine. Seven patients required more than one dose reduction. Results. Sixteen patients suffered serious adverse events. Six patients had a biopsy-proven rejection. Four of 6 patients had trough cyclosporine levels within 20% of baseline value immediately before developing rejection. Conclusion. Converting patients from the standard formulation to the microemulsion formulation of cyclosporine seems to expose stable patients to unnecessary risks.