A randomized trial with steroids and antithymocyte globulins comparing cyclosporine/azathioprine versus tacrolimus/mycophenolate mofetil (CATM2) in renal transplantation.

BACKGROUND: The best immunosuppressive regimen in benefit-risk ratio in renal transplantation is debated. Nowadays, tacrolimus (Tac) and mycophenolate mofetil (MMF) are considered more efficient than cyclosporine A (CsA) and MMF, but recent studies have challenged this assumption.

METHODS: We conducted a monocentric, prospective, open-labeled, randomized, and controlled trial comparing CsA/azathioprine (Aza) versus Tac/MMF in 289 kidney transplant recipients treated with antithymocyte globulins and prednisone. Primary outcome was the number of patients with clinically suspected acute rejection at 1 year. Secondary outcomes were the number of patients with biopsy-proven acute rejection (BPAR), estimated glomerular filtration rate (eGFR), patient and graft survivals, and adverse events at 1 and 3 years.

RESULTS: During the first year, 21 patients had clinically suspected acute rejection with CsA/Aza (14.4%) vs. 11 (7.7%) with Tac/MMF (P=0.07). BPAR, including borderline, was more frequent in the CsA/Aza group (14.4%) than in the Tac/MMF group (5.6%; P=0.013). At 1 year, patient and graft survivals were not different, and eGFR was 48±1 in the CsA/Aza group and 53±1 mL/min/1.73 m in the Tac/MMF group (P=0.007). There was no significant difference in diabetes after transplantation (16.8% and 18.8%, respectively).

CONCLUSIONS: With antithymocyte globulins and steroids, clinically suspected acute rejections did not differ between CsA/Aza and Tac/MMF arms. Analysis of secondary endpoints showed a lower rate of BPAR, including border line, and a higher eGFR in the Tac/MMF group. CsA/Aza allowed a low acute rejection rate, but Tac/MMF seemed as a better regimen regarding severe secondary outcomes.