Enfortumab Vedotin-induced Cutaneous Reactions Presenting as Pruritic Erythematous Plaques: A Case Report and Literature Review

Abstract

Enfortumab vedotin (EV) is a monoclonal antibody-drug conjugate targeting nectin-4 that is approved for treating urothelial carcinoma. Half of patients treated with EV present with adverse cutaneous reactions such as erythematous rash, blisters, and severe drug eruptions, including Stevens-Johnson syndrome and toxic epidermal necrolysis. A 54-year-old man treated with EV for metastatic urothelial carcinoma developed pruritic erythematous plaques bilaterally on his abdomen, thighs, and left lower limb two days after his first dose. Histopathologically, scattered areas of keratinocyte necrosis and superficial perivascular infiltration of lymphocytes and eosinophils were observed. Based on the clinical and pathological findings, we diagnosed cutaneous reactions induced by EV. Because EV-induced cutaneous reactions can appear as early as soon after the initial administration and can be severe, dermatologists should be involved early to diagnose any eruption.