Transplant Antibody-Mediated Rejection: Guiding Effective Treatments

Inclusion Criteria: * Willing and able to give written informed consent by patient aged 16 years and over; or by a parent or legal guardian for patients who are under 16 years old * 5 years old or older * A diagnosis of acute AMR as defined by: * The presence of ≥1 donor specific antibodies (DSA) * An adequate renal transplant biopsy with histological features consistent with active AMR with no evidence of chronicity as defined by the Banff histological classification of allograft pathology: * If C4d positive (2 or 3): * v score ≥1 and/or * g score ≥1 and/or * thrombotic microangiopathy and/or * ptc score ≥1 * or if co-existent cellular rejection, a g score of ≥1 OR * If C4d negative (0 or 1): * microcirculation inflammatory score (g + ptc) ≥2 * or if co-existing cellular rejection, a g score ≥1 and (g + ptc) ≥2 AND * Chronic glomerulopathy (cg) score 0 or 1a * Tubulo-interstitial fibrosis \<50% and glomerular obsolescence \<50% Exclusion Criteria: * Patients who have received an ABO incompatible transplant * Patients who have received rituximab as part of induction or post-transplant for any other indications (e.g. recurrent focal and segmental glomerular sclerosis) * Patients who have completed PEX treatment prior to the index biopsy on the suspicion of acute AMR in the absence of histology * Have active infection including bacterial, viral (including CMV (cytomegalovirus) and EBV (Epstein-Barr virus)), fungal or tuberculosis, which in the investigator's opinion could af…