Rituximab in the real-world treatment of lupus nephritis: A retrospective cohort study in Japan

Although recommended in established international guidelines for lupus nephritis (LN), rituximab is not officially approved for LN treatment, making all such use off-label. The Japan College of Rheumatology (JCR) conducted a retrospective observational study on real-world efficacy and safety of rituximab treatment for LN in Japan.Clinical data were collected from 47 hospitals for LN patients treated with rituximab to retrospectively investigate dosing schedule, efficacy, and safety.This retrospective analysis included 115 patients: 84 (73%) received 375 mg/m2 weekly up to four doses, and 31 (27%) received 1000 mg/body in one or two doses 2 weeks apart. Rituximab significantly improved findings for urinalysis, systemic lupus erythematosus serology, and systemic lupus erythematosus disease activity and was assessed as 'extremely effective' in 24.8% of patients and 'effective' in 60.2%. The renal response by the JCR-I criteria was 52.5% for overall response rate (ORR) (complete renal response rate 20.8% and partial renal response rate 31.7%) and that by the JCR-II criteria was 49.5% (21.8% and 27.7%, respectively). Corticosteroid dose was significantly reduced. Rituximab was well tolerated, with frequent but manageable adverse events of infusion reaction and infection.Rituximab is effective for the treatment of Japanese patients with LN refractory to conventional therapy.