Efficacy of Tralokinumab in a Patient with Atopic Dermatitis Experiencing Loss of Response to Dupilumab: A Case Report

Atopic dermatitis (AD) is driven by a self-perpetuating cycle of immune dysregulation and skin barrier dysfunction. While dupilumab provides sustained efficacy for moderate-to-severe disease, a subgroup of patients may experience a secondary loss of response, creating a therapeutic challenge due to limited real-world data. We present a 36-year-old male with severe upper-body AD (initial BSA 15%, pruritus 7/10) who achieved rapid clearance on dupilumab, maintaining a stable response for three years before experiencing a breakthrough flare (BSA 5%, pruritus 6/10). The adjunct introduction of delgocitinib cream, used to treat chronic hand eczema (CHE), alongside increased dupilumab frequency to weekly dosing yielded only partial clearance (BSA 2%, pruritus 6/10). Due to incomplete resolution, the patient transitioned to tralokinumab, an IL-13 inhibitor. After 12 weeks, the patient achieved complete clearance (BSA 0%, pruritus 0/10). This clinical case demonstrates that managing a secondary biologic failure does not necessitate a disruptive class switch to oral JAK inhibitors, IL-31 inhibitors, or traditional systemic immunosuppressants; rather, staying in class with a more targeted IL-13 inhibitor remains a highly effective strategy.