Multiple cycles of rituximab therapy for pemphigus: A group of patients with difficult- to-treat disease or a consequence of late rituximab initiation?

Abstract

Pemphigus is a serious autoimmune disease with few appropriate therapeutic options. Although rituximab (RTX) has recently shown great promise in this regard, the best protocol of its administration is remains to be elucidated. This study aimed to evaluate the patients who need at least 3 cycles of treatment with RTX to identify hard-to-treat patients' characteristics, which might lead to consider more prompt protocols for treatment of them. A retrospective cross-sectional study was conducted on 45 patients with pemphigus vulgaris who received at least 3 cycles of RTX. Their demographic, clinical, and laboratory data as well as details of treatment protocol and final clinical situation of patients were evaluated. Totally, 45 patients (21 men and 24 women) with mean age of 44.33 years were included in this paper. Women were about 8 years older than men (mean age: 48.1 years versus 40.1 years, p: 0.011) and needed RTX approximately 2 years later in their course of disease (gap: 41.04 months vs. 14.85 months, p: 0.003). Buccal, truncal, and scalp regions were the most frequent sites of involvement respectively. A significant decrease in both anti-Dsg1, 3 was seen at last visit compared to baseline. However, the amount of this decrement was not significantly different between them (p: 0.083). Partial remission in 31.11%, complete remission in 24.44%, relapse in 15.56%, partial remission on treatment in 15.56% and complete remission on treatment in 13.33% were seen at the last follow-up session. RTX is an effective medication for PV even in patients with refractory disease and its therapeutic effect is increased with each subsequent cycle. Male gender, severe oral mucosal involvement on disease onset and extensive scalp and truncal lesions as first cutaneous manifestation of disease are more likely to be signs of refractory PV. Hence, it is reasonable to consider more prompt protocols for treatment of these cases. Moreover, late prescription of RTX during the course of disease might play a role in presence of more resistant form of disease.