Supplementary Material for: Two cases of exacerbation of asthma during treatment with enfortumab vedotin

Enfortumab vedotin is an antibody-drug conjugate against nectin-4 that is recently being used in the management of patients with urothelial carcinoma. The common adverse events include rashes, peripheral neuropathy, and hyperglycemia. Only a few cases of associated respiratory symptoms have been reported. Herein, we describe two patients with advanced urothelial carcinoma who experienced asthma exacerbation after initiating enfortumab vedotin treatment. Both patients improved with inhalation therapy. Since nectin-4 is expressed in the tracheal epithelium, its association with asthma is likely. This study highlights that clinicians should caution patients with a history of asthma against the worsening of respiratory symptoms when enfortumab vedotin is administered.