Rituximab therapy for refractory autoimmune bullous diseases: A multicenter, open‐label, single‐arm, phase 1/2 study on 10 Japanese patients

Abstract

This was a multicenter study of rituximab, a chimeric monoclonal immunoglobulin G antibody directed against CD20, for the treatment of refractory autoimmune bullous diseases (pemphigus and pemphigoid). Ten patients (three with pemphigus vulgaris, six with pemphigus foliaceus and one with bullous pemphigoid) were treated with a single cycle of rituximab (four weekly infusions at a dose of 375 mg/m2 of body surface area). The primary end‐points were the number of serious adverse events and rate of complete remission at 40 weeks. Five patients (50%) achieved complete remission with minimal therapy (defined as no active lesions with lower doses of systemic corticosteroids compared to that with prednisolone 10 mg/day). Improvements in clinical scores (Pemphigus Disease Area Index) and decreases in autoantibody titers in the sera were observed in the four pemphigus patients who failed to achieve complete remission. This suggests that rituximab was effective in nine of 10 cases. Two serious adverse events (Pneumocystis carinii pneumonia and septic shock due to infectious arthritis) were observed and adequately treated with hospitalization. CD19‐positive B lymphocytes in the peripheral blood decreased on day 29 following rituximab treatment, and remained at low levels throughout the observation period (280 days). Our results confirmed the efficacy of rituximab therapy for refractory autoimmune bullous diseases in Japan.

Efficacy of Rituximab in the treatment of pemphigus: experience of Moroccan population

“…All cases demonstrated significant improvement or complete remission and most experienced no adverse events [4][5][6][7][8] Rituximab appears to be both well tolerated and efficacious for refractory juvenile pemphigus foliaceus [6]. Therefore, it may be considered for severe cases of PF to avoid side effects associated with conventional glucocorticoid therapy [5,[7][8][9][10]. This study reinforces the beneficial role of rituximab in pemphigus in our context.…”

Rituximab Therapy for Treatment of Pemphigus in Southeast Asians

“…33 The rate of CR on therapy in the literature has ranged from 50-89.5% following the first rituximab infusion, which is tantamount to ours. 24,[34][35][36] Our data show that CR off therapy occurred in 34% of the patients within 19.74 months. That rate is rather inferior to the figures in previous reports, where approximately 36.6-89.5% of the cases achieved CR off therapy.…”

Myasthenia Gravis With Antibodies Against Muscle Specific Kinase: An Update on Clinical Features, Pathophysiology and Treatment

“…In MuSK-MG patients, rituximab treatment appears to be particularly effective and this could be because IgG4 antibodies sustain the main pathogenic mechanism of the disease. Short-lived plasma cells producing IgG4 antibodies may be more susceptible to the drug as indicated by studies on other diseases caused by IgG4 antibodies (such as pemphigus and IgG4-related disease) in which significant clinical improvement and reduction in antibody titers were observed (Khosroshahi et al, 2010 ; Díaz-Manera et al, 2012 ; Carruthers et al, 2015 ; Kamisawa and Okazaki, 2017 ; Kurihara et al, 2019 ). The use of rituximab treatment in MuSK-MG is supported by several case reports, local studies, and, more recently, by bigger nation-wide group analysis (Hain et al, 2006 ; Khosroshahi et al, 2010 ; Nowak et al, 2011 ; Díaz-Manera et al, 2012 ; Keung et al, 2013 ; Hehir et al, 2017 ; Topakian et al, 2019 ).…”