Rituximab as an effective add-on maintenance therapy for disease activities in childhood-onset systemic lupus erythematosus.

Objectives: Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease that can result in high morbidity if not treated. This retrospective study aimed to evaluate the outcomes of rituximab treatment in a paediatric SLE cohort in Taiwan.

Methods: The medical records of paediatric patients diagnosed with SLE at the National Taiwan University Hospital between January 1992 and August 2022 who received rituximab as maintenance therapy between January 2015 and August 2022 were retrospectively reviewed. To enhance our analysis, we included a contemporary comparison group, matching in case number and demographic characteristics. This study aimed to describe the indications, efficacy and safety of rituximab in the treatment of paediatric SLE and to analyse the factors associated with disease outcomes.

Results: The study included 40 rituximab-treated patients with a median age of 14.3 years at the time of disease diagnosis. In the rituximab-treated cohort, the median score on the Systemic Lupus Erythematosus Disease Activity Index 2000 decreased from 8 before rituximab administration to 4 after 2 years. The levels of C3 and C4 increased and anti-double stranded DNA (anti-dsDNA) levels decreased significantly within 6 months. The equivalent oral prednisolone dose halved after 6 months. Finally, 8 (20%) patients achieved disease control and 35 (87.5%) patients had no flare-ups during the follow-up period (median, 2 years). Those patients who achieved disease control had a significantly shorter interval between diagnosis and rituximab administration. In terms of adverse effects, only one patient developed hypogammaglobulinaemia that required intravenous immunoglobulin (IVIG) replacement. Compared with the comparison group (n=53), the rituximab-treated cohort exhibited superior disease outcomes and a reduced incidence of flare-ups.

Conclusions: This study provides real-world data and illuminates rituximab's role in maintaining disease stability among patients with paediatric-onset SLE who are serologically active without major clinical deterioration. Most importantly, no mortality or development of end-stage renal disease was observed in the rituximab-treated cohort.