LAUSR

OBJECTIVE We investigated the effectiveness of rituximab (an anti-CD20 monoclonal antibody) in patients with eosinophilic granulomatosis with polyangiitis (EGPA). METHODS We performed a systematic literature review from the inception dates until July 20, 2020 for articles reporting rituximab administration to treat EGPA. RESULTS We identified a total of 171 patients; most of the patients had refractory or relapsing disease, whereas 14 patients were newly diagnosed with EGPA. Rituximab was used for induction therapy in all patients and administered as four infusions of 375 mg/m2/week, or two infusions of 1000 mg, given 2 weeks apart. The observation period was 6-36 months after rituximab initiation. The remission rates (defined as a Birmingham Vasculitis Activity Score of 0 along with low dose glucocorticoid) were 36 to 100%. Anti-neutrophil cytoplasmic antibody (ANCA)-positive patients tended to respond better to rituximab than ANCA-negative patients. All studies reported the successful reduction of glucocorticoid dose after rituximab treatment. The median glucocorticoid dose at rituximab initiation was 12.5-60 mg/day, which was successfully reduced to 0-8.5 mg/day after rituximab treatment. Scheduled rituximab maintenance treatment significantly reduced the relapse rates as compared to rituximab administered on demand. No new safety signal was reported. CONCLUSION Rituximab effectively induced and sustained remission and reduced glucocorticoid dose in patients with newly diagnosed or relapsing and refractory EGPA; it also showed potentially greater benefit in ANCA-positive patients than in ANCA-negative patients.