030 Immune checkpoint inhibitor-induced bullous pemphigoid skin has elevated interleukin-4 and interleukin-13 expression and responds to IL-4R inhibition

Abstract

Immune check point inhibitors (ICIs) have revolutionized the treatment of advanced malignancies but can induce skin toxicities including ICI-induced bullous pemphigoid (BP). The pathogenesis of ICI-induced BP is unclear and selection of effective treatment options that do not inhibit the anti-tumor response is a challenge. If cytokine expression in ICI-induced BP and conventional BP skin is similar, emerging therapies for conventional BP may be effective for ICI-induced BP as well. RNA-in situ hybridization was utilized to examine expression of IL4Rα ligands, IL4 and IL13, in formalin-fixed paraffin-embedded skin biopsy specimens from patients with conventional BP, ICI-induced BP, atopic dermatitis and normal, control skin.