Background: Corticosteroids and calcineurin inhibitors (CNIs) are included in renal transplantation immunosuppressive protocols around the world. Well-known side effects are associated with the use of these drugs, including new onset of diabetes after transplantation (NODAT). Long-term patient survival rates are lower among patients with NODAT. The optimal immunosuppressive protocol would therefore include not using corticosteroids and minimization of CNI use.
Methods/design: This is a prospective, multi-centre, controlled, randomized, parallel group, open-label study involving kidney transplant patients. The study compares a steroid-free immunosuppressive protocol (study arm A), which is based on low-dose tacrolimus and mycophenolate mofetil (MMF) maintenance therapy together with antithymocyte globulin (ATG) induction, with the conventional immunosuppressive protocol (study arm B), being based on low-dose tacrolimus, MMF and steroids together with interleukin-2 receptor (IL2-R) induction. The study is designed to include most normal-risk patients. It will exclude patients seen as at a high risk of rejection. The primary objective of the study is to assess the cumulative incidence of NODAT in the two study arms 12 months after transplantation using the American Diabetes Association type 2 diabetes diagnostic criteria. The composite measure of freedom from acute rejection, graft survival and patient survival will be evaluated. Renal function and chronic changes in the transplanted kidney will be assessed.
Discussion: If this study confirms conceptual expectations, namely decreased incidence of NODAT, the steroid-free study protocol could be used with all patients. The regimen could be especially beneficial for patients at a high risk of diabetes mellitus.
Trial registration: EudraCT 2012-000451-13.
Keywords: diabetes; immunosuppression; renal transplantation.