CD38 mAb Induction + Azathioprine Maintenance for Chronic Active AMR in Kidney Transplant Recipients

This multicenter, prospective, single-arm exploratory study evaluates the efficacy and safety of a novel sequential regimen for chronic active antibody-mediated rejection (caABMR) in kidney transplant recipients: single-dose CD38 monoclonal antibody (1800 mg subcutaneous) induction to deplete plasma cells and NK cells, followed by long-term maintenance with azathioprine (replacing mycophenolate mofetil) plus standard triple immunosuppression (steroid + calcineurin inhibitor). The regimen aims to control DSA-driven injury, stabilize or improve graft function (primary: eGFR decline slope), reduce DSA, improve pathology (Banff 2022), and minimize infection/nephrotoxicity risks associated with intensified or prolonged biologic therapy. Twenty patients across 6 Chinese transplant centers will be enrolled. CD38 mAb, azathioprine, key monitoring tests (HLA antibody, pharmacogenomics, immune profiling) are provided free by the study team (\~40,000 RMB per patient). Ethics approved; informed consent obtained.