Conversion From Mycophenolate Mofetil to Azathioprine in Renalallograft Patients Within the First Month Posttransplantation

This retrospective study evaluated the safety of conversion from mycophenolate mofetil (MMF) to azathioprine (Aza) within the first month posttransplantation in 117 renal allograft patients concomittantly treated with cyclosporine (CsA) and prednisone. In 52 Conversion from MMF to Aza was conducted at 2 to 4 weeks posttransplantation in 52 patients (conversion group). Thirty-six patients received MMF (MMF group) and 29 patients were treated with Aza (Aza group). Patients were monitored for allograft function, acute rejection episodes, and CsA levels. The demographics were comparable between groups with respect to age, as well as warm and cold ischemic times of allografts. The cumulative allograft survival rates at 1, 2, 3, and 5 years were 98% ± 2%, 96% ± 3%, 90% ± 4%, 90% ± 4% in the conversion (n = 52) group versus 79% ± 7%, 79% ± 7%, 79% ± 7%, and 75% ± 8% in the MMF group (n = 36) versus 93% ± 5%, 93% ± 5%, 82% ± 7%, and 78% ± 8% in the Aza group (n = 29). The CsA trough levels at 1 year posttransplantation were 208.39 ± 93.79 ng/mL in the conversion group; 159.30 ± 52.99 ng/mL in the MMF group; and 241.82 ± 112.76 ng/mL in the Aza group. The acute rejection rates during a 5-year follow-up were 28.85% in the conversion group; 27.78% in the MMF group; and 24.14% in the Aza group. The rejection-free allograft survival between the conversion group and the MMF group was identical (P < .921). However, allograft survival in the conversion group with acute rejection was significantly higher than the MMF group (P < .024). In conclusion, early conversion from MMF to Aza among renal allograft patients was safe without increased acute allograft rejection during a 5-year follow-up. The overall allograft survival in the conversion group was comparable to patients treated with MMF or Aza therapies.