Comparison of alemtuzumab vs. antithymocyte globulin induction therapy in primary non‐sensitized renal transplant patients treated with rapid steroid withdrawal

Alemtuzumab and rabbit antithymocyte globulin (r ATG ) are commonly used for induction therapy in renal transplantation. This retrospective, single‐center, cohort study evaluated cumulative incidence of one‐yr biopsy‐proven acute rejection ( BPAR ) among 200 consecutive primary non‐sensitized kidney transplant recipients who received either alemtuzumab (n = 100) or r ATG (n = 100) induction followed by rapid steroid taper, tacrolimus, and mycophenolate mofetil. Protocol biopsies, plasma and urine BK virus PCR , serum creatinine and iothalamate glomerular filtration rate (iGFR), were obtained at 1, 4, and 12 months from transplantation. The one‐yr BPAR rates were similar between the alemtuzumab and rATG groups; however, rejection Banff IA and higher was more common in the alemtuzumab arm (18% vs. 5%, p = 0.047). After adjusting for confounding variables, alemtuzumab was still associated with Banff IA and higher rejection (adjusted OR: 3.7, CI: 1.2–10.5, p = 0.02). Despite similar rates of BK viremia, more patients in the alemtuzumab arm developed BK nephropathy (16% vs. 3%, p = 0.046). One‐year iGFR (53.4 ± 20.2 vs. 71.9 ± 27.2 mL/min/1.73 m 2 , p   =   0.002) and three‐yr graft survival (89.5% vs. 95%, p = 0.05) were lower in the alemtuzumab group. In low immunological risk kidney transplant recipients on steroid‐free immunosuppression, alemtuzumab was associated with more severe rejection and BK nephropathy compared to r ATG .