Paradoxical Worsening of Eczematous Cutaneous Immune-Related Adverse Events Associated with Dupilumab: Two Cases

This letter presents two cases of patients with immune checkpoint inhibitor-induced eczematous cutaneous immune-related adverse events (cirAEs) who experienced rapid and severe paradoxical worsening following dupilumab administration. Both patients achieved clinical improvement with methotrexate-based therapy, with short-course systemic corticosteroids added when needed, while anticancer therapy was maintained and no tumour progression was observed during follow-up. These findings highlight the need for cautious use of dupilumab in cirAE patients under immune checkpoint inhibitor treatment, and suggest that conventional systemic agents remain important options when balancing cutaneous toxicity control with continuity of cancer treatment.