Ciltacabtagene Autoleucel in Monoclonal Gammopathy of Renal Significance

A 63-year-old woman with IgG Kappa monoclonal gammopathy of undetermined significance (MGUS) presented with progressive proteinuria and kidney dysfunction. Sequential biopsies eventually revealed collapsing focal segmental glomerulosclerosis ( FSGS) with light chain crystalline podocytopathy (LCCP), diagnostic of monoclonal gammopathy of renal significance (MGRS). Despite multiple clone-directed regimens, she progressed to kidney failure. Treatment with ciltacabtagene autoleucel (cilta-cel), a B-cell maturation antigen (BCMA) directed chimeric antigen receptor (CAR) T-cell therapy, achieved complete hematologic remission sustained at 6 months. This case highlights the therapeutic potential of CAR T-cell therapy for refractory MGRS and evolving considerations for kidney transplantation following deep clonal remission.