A Study to Assess the Efficacy and Safety of Advagraf® Switching From Cyclosporine Between the Group That Was Treated With a 50% Reduced Corticosteroid and the Group With Maintained Corticosteroid for Stable Kidney Transplant Recipients

The primary objective is to assess the changes in the GFR after 24 weeks of treatment between the group that was reduced corticosteroid slowly until 50% lower dose from 4 weeks to 12 weeks and the group with maintained corticosteroid in stable kidney transplant subjects whose regimen was converted from a CyA-based immunosuppressive regimen with corticosteroid to an Advagraf®-based immunosuppressive regimen with corticosteroid for kidney transplant subjects whose regimen was converted from a CyA-based immunosuppressive regimen. The secondary objective is to assess the creatinine clearance rate, acute rejection, satisfaction of medication and safety of the group with a 50% reduced dose of corticosteroid and the group in which the Advagraf ®-based immunosuppressive regimen with maintained corticosteroid.