Efficacy of belimumab in children with systemic lupus erythematosus

To evaluate the efficacy and safety of belimumab combined with standard therapy in children with systemic lupus erythematosus (SLE) in a single-center retrospective observational cohort. A total of 60 children with active SLE were screened, and 40 eligible patients were included. Patients were classified into a belimumab plus standard therapy group ( n = 20) and a standard therapy alone group ( n = 20). Belimumab was administered intravenously at 10 mg/kg every 2 weeks for the first three doses and every 4 weeks thereafter. Clinical manifestations, laboratory parameters, SLEDAI-2000 scores, glucocorticoid doses, and adverse events were compared between groups. The 6-month assessment was considered the primary observation time point, while 12-month outcomes were exploratory. At 6 months, renal and mucocutaneous remission rates were 83% (15/18) and 94% (15/16) in the belimumab group, compared with 78% (7/9) and 85% (11/13) in the control group. At 12 months, the corresponding rates were 94% (15/16) and 94% (15/16) in the belimumab group, and 89% (8/9) and 85% (11/13) in the control group. C3, C4, and SLEDAI-2000 scores improved significantly in both groups. Most clinical and serological outcomes did not differ significantly between groups. Oral glucocorticoid doses decreased more markedly in the belimumab group than in the control group (53.55 ± 8.43 to 6.72 ± 3.50 mg/day vs. 55.50 ± 6.05 to 14.81 ± 5.54 mg/day; P < 0.05). One patient experienced reversible reductions in IgG levels and B-cell counts, with no severe infections or infusion reactions. Belimumab plus standard therapy showed a potential glucocorticoid-sparing effect in pediatric SLE, but larger prospective studies are needed to confirm its efficacy and safety.