Efficacy of Telitacicept in Childhood‐Onset Systemic Lupus Erythematosus: A Prospective Multicenter Cohort Study With Inverse Probability of Treatment Weighting –Adjusted Comparison to a Historical Control Group Treated With Belimumab

Objective The therapeutic effects of telitacicept combined with standard of care (SoC) in childhood‐onset systemic lupus erythematosus (cSLE) remain unclear. This study aims to evaluate its efficacy in comparison with belimumab combined with SoC. Methods We performed a prospective cohort study across seven tertiary hospitals in China, enrolling patients aged 5 to 18 years with cSLE. Primary endpoints included the proportions of patients attaining Lupus Low Disease Activity State (LLDAS) and Definition of Remission in SLE (DORIS) at 3, 6, and 12 months after treatment, complemented by relapse rates and steroid tapering metrics. Propensity score–based inverse probability of treatment weighting (IPTW) was employed to address baseline imbalances between the telitacicept group (n = 60) and the historical control group treated with belimumab (n = 67). Results Among 60 enrolled patients (median follow‐up 12 [interquartile range 6–12] months), LLDAS and DORIS achievement rates progressively increased from 19.6% and 7.8% at 6 months to 65.7% and 37.1% at 12 months. Flare rates remained low (3 months: 1.7%; 6 months: 11.8%; 12 months: 14.3%). Notably, 74.3% of patients achieved prednisone doses ≤7.5 mg/day by 12 months (vs baseline 13.3%, P < 0.0001). IPTW‐adjusted analyses demonstrated comparable efficacy between the telitacicept and belimumab groups across all endpoints in terms of LLDAS and DORIS attainment, steroid reduction, and immunologic normalization (all P > 0.05). Conclusion Telitacicept combined with SoC exhibited significant improvements in disease activity, steroid reduction, and immunologic markers, with therapeutic outcomes comparable to belimumab in cSLE management.