Significance of HLA-B*15 in three pemphigus patients with rituximab-triggered severe cutaneous drug reactions.

Abstract

Introduction: Rituximab, a CD20 inhibitor, has swiftly become the primary treatment for pemphigus patients.

Aim: We present 3 cases of pemphigus patients who had undergone rituximab treatment.

Material and methods: After the second intravenous administration of rituximab, the primary rash developed into severe cutaneous drug reactions. Peripheral blood was collected from the aforementioned 3 patients for the detection of susceptibility genes by using second-generation sequencing.

Results: Notably, a significant resemblance was observed in the HLA profiles of these 3 patients, particularly regarding high-risk alleles associated with rituximab-induced severe cutaneous drug reactions (CDRs). This rare occurrence of severe CDRs post-rituximab administration may be HLA-dependent and linked to HLA-B*15:02:01, HLA-B*15:12 and HLA-B*15:27:01. This pioneering laboratory trial shows the pathological background of rituximab-induced severe cutaneous drug reactions.

Conclusions: Our findings contribute to the expanding catalogue of potential HLA-B*15 linked to severe CDRs and underscore the importance of vigilance regarding such reactions in pemphigus patients undergoing rituximab therapy.