Effectiveness and safety of rituximab in special types of rheumatoid arthritis

To elucidate the efficacy and safety of rituximab in special types of rheumatoid arthritis.

We retrospectively reviewed all patients with rheumatoid arthritis with lymphoproliferative disorder or vasculitis treated with rituximab between April 2010 and June 2022 at Keio University Hospital. We assessed the effectiveness of rituximab using the Disease Activity Score for 28 joints-erythrocyte sedimentation rate (DAS28-ESR), Clinical Disease Activity Index (CDAI), and safety of rituximab during the disease course. We also assessed the glucocorticoid-sparing effects of rituximab.

We included eight patients with a history of lymphoproliferative disorder and five patients with rheumatoid vasculitis. They were treated with rituximab without high-dose glucocorticoid. The mean DAS28-ESR and CDAI scores significantly improved 12 months after rituximab administration (DAS28-ESR, 4.7 vs. 2.7, p < .001; CDAI, 16.0 vs. 5.1, p = .006, respectively), and the dose of prednisolone was reduced from a mean of 7.4 mg/day to 4.0 mg/day at 12 months (p = .05) and 3.2 mg/day at the last visit (p = .04). During the mean follow-up period of 52 months, we recorded one recurrence of lymphoproliferative disorder (not B-cell type) in patients with a history of lymphoproliferative disorder and remarkable improvement of skin ulcers in patients with vasculitis.

B-cell depletion by rituximab may be a useful treatment option for patients with lymphoproliferative disorder and rheumatoid vasculitis.