037 Efficacy and safety of tirabrutinib, highly selective Bruton’s tyrosine kinase inhibitor, for oral treatment of pemphigus: a multicenter, open-label, uncontrolled, single-arm phase 2 study

Abstract

Bruton’s tyrosine kinase (BTK) enhances BCR-stimulated proliferation, costimulatory molecule expression, and antibody production in B cells. Tirabrutinib is a highly selective oral BTK inhibitor that is expected to inhibit the immunoglobulin G autoantibody-mediated mechanism that plays a central role in the pathophysiology of pemphigus. The aim of this study was to investigate the efficacy and safety of tirabrutinib in patients with refractory pemphigus. In this multicenter, open- label, single-arm phase 2 study, patients received postprandial oral tirabrutinib 80 mg once daily for 52 weeks.