CICLOSPORINE inhibits antibody and cell-mediated immune responses and is the drug of choice for prevention of transplant rejection.
Ciclosporine (also cyclosporin) binds to cyclophilin (an intracellular protein of the immunophilin family), while everolimus (derivative of sirolimus), sirolimus, and tacrolimus bind to a protein called FKBP12, another immunophilin. For all of these drugs, the drug-protein complex then inhibits calcineurin phosphatase and T-cell activation. Nephrotoxicity is the major side effect of ciclosporine.