Rabbit anti‐thymocyte globulin for the prevention of acute rejection in kidney transplantation

This report describes the results of 2 international randomized trials (total of 508 kidney transplant recipients). The primary objective was to assess the noninferiority of rabbit anti‐thymocyte globulin (rATG, Thymoglobulin(®)) versus interleukin‐2 receptor antagonists (IL2RAs) for the quadruple endpoint (treatment failure defined as biopsy‐proven acute rejection, graft loss, death, or loss to follow‐up) to serve as the pivotal data for United States (US) regulatory approval of rATG. The pooled analysis provided an incidence of treatment failure of 25.1% in the rATG and 36.0% in the IL2RA treatment groups, an absolute difference of −10.9% (95% confidence interval [CI] −18.8% to −2.9%) supporting noninferiority (noninferiority margin was 10%) and superiority of rATG to IL2RA. In a meta‐analysis of 7 trials comparing rATG with an IL2RA, the difference in the proportion of patients with BPAR at 12 months was −4.8% (95% CI −8.6% to −0.9%) in favor of rATG. In conclusion, a rigorous reanalysis of patient‐level data from 2 prior randomized, controlled trials comparing rATG versus IL‐2R monoclonal antibodies provided support for regulatory approval for rATG for induction therapy in renal transplant, making it the first T cell–depleting therapy approved for the prophylaxis of acute rejection in patients receiving a kidney transplant in the United States.