This retrospective cohort study evaluated the therapeutic efficacy and safety profile of telitacicept, a novel dual B-cell-activating factor (BAFF)/a proliferation-inducing ligand (April) inhibitor, in managing systemic lupus erythematosus (SLE) patients with lupus nephritis (LN) and nephrotic syndrome (NS), with particular focus on renal and hematological parameters. This evidence concerns the gene TNFSF13B and Netherton syndrome.