The impact of mycophenolate mofetil versus azathioprine as adjunctive therapy to cyclosporine on the rates of renal allograft loss due to glomerular disease recurrence

Abstract

Given the reported efficacy of mycophenolate mofetil (MMF) in the treatment of glomerular diseases, we question whether MMF can reduce the rate of renal allograft loss due to glomerular disease recurrence compared to azathioprine (AZA) as adjunctive therapy to cyclosporine (CSA)-based immunosuppression. This is a retrospective study based on the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) database designed to compare the Kaplan-Meier rates of graft loss due to disease recurrence stratified by primary renal diagnoses between recipients receiving CSA+AZA versus CSA+MMF. Recipients of primary kidney transplants (both deceased donor and living, related and unrelated) renal transplants performed between 1 January 1988 and 31 December 2007 with the primary renal diagnosis of IgA nephropathy (IgAN), membranous glomerulonephropathy (MGN), membranoproliferative glomerulonephropathy (MPGN), lupus nephritis (LN) or focal segmental glomerulosclerosis (FSGS) with a functioning allograft at discharge were included. Seven thousand eight hundred and twenty-six recipients of primary deceased donor kidney transplants (DDKT) [CSA + AZA: IgAN (890), MGN (380), MPGN (193), LN (1324), FSGS (1314) and CSA+MMF: IgAN (855), MGN (614), MPGN (116), LN (715), FSGS (1425)] and 5498 recipients of living donor kidney transplants (LDKT) [CSA+AZA: IgAN (694), MGN (229), MPGN (100), LN (592), FSGS (654) and CSA+MMF: IgAN (1066), MGN (435), MPGN (89), LN (530), FSGS (1109)] were included in the analysis. At 10-year follow-up (mean duration was 5.6 to 6.7±1.8 years in DDKT and 6.2 to 7.4±1.7 years in LDKT), mean times of transplantation (era of transplantation) were: 1992±1.6 years and 2002±1.9 years for the CSA+AZA and CSA+MMF groups, respectively. There was no statistically significant difference in the Kaplan-Meier rates of graft loss due to disease recurrence of any glomerular disease studied between the CSA+AZA and CSA+MMF groups in either DDKT or LDKT recipients. Chi-square analysis revealed no statistically significant difference between the two immunosuppressive regimen groups in terms of age, gender and ethnic background. The OPTN/UNOS database revealed no difference in the rates of renal allograft loss due to disease recurrence of IgAN, MGN, MPGN, LN and FSGS among recipients receiving either CSA+AZA or CSA+MMF maintenance immunosuppressive therapy at 10-year follow-up.