Efficacy and Safety of Tocilizumab in the Treatment of Acute Active Antibody-mediated Rejection in Kidney Transplant Recipients

Background. Antibody-mediated rejection (AMR) continues to have a deleterious impact on kidney allograft survival. Recent evidence supports use of tocilizumab for treatment of chronic active AMR, but it has not been assessed for treatment of acute active AMR. Methods. We performed a single-center, observational study of kidney transplant recipients who received at least 1 dose of tocilizumab in addition to conventional therapies for acute active AMR between October 2016 and October 2018 with follow-up through August 2019. Results. Seven patients were included. All 7 patients received tocilizumab 8 mg/kg (max dose, 800 mg) monthly. We noted a 50% or greater reduction in immunodominant donor-specific antibodies in 4 of 6 patients. Renal function improved or stabilized in all patients throughout the duration of therapy. One patient developed cytomegalovirus esophagitis and 1 had a potential hypersensitivity reaction. In the extended follow-up, 1 patient had mixed rejection and 2 patients had T-cell-mediated rejection, which occurred 6 to 24 mo after completion of therapy. Conclusions. Tocilizumab may be considered as an addition to conventional therapies for treatment of acute active AMR. More studies are needed to determine which patients may benefit from therapy and to examine the appropriate duration of treatment.