Tocilizumab as Adjuvant Therapy in Refractory Antibody Mediated Rejection in Pediatric Kidney Transplant Recipients

ABSTRACT Background Antibody mediated rejection (ABMR) is a major cause of graft loss in kidney transplantation. There are limited treatment options with poor efficacy. Intravenous tocilizumab has been reported to be of benefit in a small number of patients. We provide further evidence of efficacy in pediatric patients and show successful switch to subcutaneous tocilizumab. Methods Retrospective case note review of all patients treated with Tocilizumab for ABMR at our institution. Clinical and demographic data, including kidney function, donor specific antibody (DSA) status, and histopathology reports were collected from the electronic medical record. Results Six patients, median age 12.7 years at the start of Tocilizumab treatment and a median time of 5.2 years post‐kidney transplant, were included. All patients had histological evidence of chronic active ABMR. Five had anti‐human leukocyte antigen (HLA) DSA and one had anti‐angiotensin receptor 1 (ATIR) antibodies only. All patients were previously treated with intravenous immunoglobulin, ± plasmapheresis ± rituximab. There was a decrease in DSA in all patients and stabilization of kidney function in five. Results were sustained after switching to subcutaneous drug in four. All six had repeat biopsies demonstrating stabilization, but no improvement, of the Banff grading of ABMR. Two patients ceased Tocilizumab after presenting with sepsis‐like episodes, one patient ceased due to non‐compliance, and one developed severe recurrent stomatitis and had their dose interval increased. Conclusions Tocilizumab is an effective adjuvant to conventional therapy in some children with ABMR and can be given subcutaneously. Clinicians should be aware of potential adverse effects.