Telitacicept in IgA Nephropathy Patients with Severe Renal Impairment: A Case Series

Background: Treatment options for IgA nephropathy (IgAN) patients with severe renal impairment are limited. Although telitacicept is approved for reducing proteinuria in IgAN, prior trials excluded patients with estimated glomerular filtration rate (eGFR) 1 g/day who received ≥24 weeks of telitacicept between March 2023 and June 2024. Proteinuria, eGFR, and serum immunoglobulins were assessed longitudinally. Results: Thirteen patients were included. Proteinuria decreased by 45% at Month 6 and remained reduced by 51%, 47%, and 45% at Months 12, 18, and 24, respectively. One patient initiated dialysis at Month 15. Mean eGFR remained stable over 24 months, with an annual decline slope of -2.39 mL/min/1.73 m²/year. In eight patients, serum IgA fell from 2.93 ± 0.78 to 0.78 ± 0.28 g/L (P = 0.001) and IgG from 11.16 ± 2.92 to 6.53 ± 2.85 g/L (P < 0.001) at Month 6, both stable through Month 12. Combination therapy with glucocorticoids achieved greater proteinuria reductions at Months 1–6 and a more favorable eGFR slope (+0.95 ± 6.37 vs. -3.88 ± 3.76 mL/min/1.73 m²/year) than monotherapy. Conclusion: Telitacicept reduced proteinuria and stabilized eGFR in IgAN patients with severe renal impairment. It may be a therapeutic option for patients unresponsive or intolerant to conventional therapy, but confirmation in larger, prospective studies is warranted.