Clinical and mechanistic differences between FK506 (tacrolimus) and cyclosporin A

Abstract

Cyclosporin A (CsA) and FK506 (tacrolimus) are potent immunosuppressive drugs widely used in reducing the incidence and severity of allograft rejection after organ transplantation. Owing to their capacity to antagonize calcineurin activity and hence calcium‐dependent T‐cell activation [1], both drugs were thought to have identical cellular and molecular effects, despite differences in their structure [2].