Abstract
BACKGROUND: Lupus nephritis (LN) is a severe complication of systemic lupus erythematosus with suboptimal response to standard therapy. This study evaluated the efficacy and safety of telitacicept, a novel fusion protein targeting both BLyS and APRIL, combined with standard therapy in patients with active LN. METHODS: This retrospective study included 67 patients with biopsy-proven LN treated with telitacicept plus standard therapy between January 2022-July 2024. Primary endpoints included renal response rates, SRI-4, and safety at weeks 12, 24, and 52. FINDINGS: Complete and partial renal response rates were 41.8%/26.9% at week 12 (n=67), 48.9%/34.0% at week 24 (n=47), and 56.3%/37.5% at week 52 (n=16). SRI-4 response rates increased from 55.2% at week 12 to 75.0% at week 52 (p=0.035 for trend). Proteinuria decreased significantly from 2.69g/24h at baseline to 0.51g/24h at week 24 (p<0.001). Median prednisone dose decreased from 40mg at baseline to 7.5mg at week 52 (p<0.001). Thirteen adverse events occurred with no serious events reported. INTERPRETATION: Telitacicept combined with standard therapy demonstrated significant efficacy in LN with an acceptable safety profile, achieving high response rates, reduced proteinuria, improved immunological parameters, and substantial glucocorticoid-sparing effects.