Psoriasis and Seronegative Spondyloarthropathy in Atopic Dermatitis Patients Treated with Dupilumab or Tralokinumab: A Multicentre Observational Study

Background Biologic therapies such as dupilumab and tralokinumab have greatly impacted the management of moderate-to-severe atopic dermatitis (AD). However, recent clinical observations have reported paradoxical adverse events, including psoriasis and seronegative spondyloarthropathy (SpA).Objectives To assess the incidence, clinical characteristics and management of psoriasis and SpA in patients with AD treated with dupilumab or tralokinumab in a real-world setting.Methods We conducted a multicentre retrospective observational study involving patients with AD receiving dupilumab or tralokinumab for >= 16 weeks between January 2019 and May 2025. Data were collected on patients developing psoriasis and/or SpA, including demographics, time to onset, severity, management strategies and treatment outcomes.Results Psoriasis developed in 78 of 5899 patients (1.3%) receiving dupilumab and 16 of 769 (2.1%) on tralokinumab, with respective mean times to onset of 57.7 (SD 66.5) and 28.3 (28.9) weeks. SpA occurred in 17 patients (0.3%) on dupilumab and 1 (0.1%) on tralokinumab. Topical calcipotriol/betamethasone was the most frequent treatment for psoriasis, while systemic agents, including methotrexate and corticosteroids, were required in refractory cases. In addition, a proportion of patients required switching to alternative biologics due to poor disease control. For SpA, management often involved systemic corticosteroids, nonsteroidal anti-inflammatory drugs or methotrexate, and upadacitinib was introduced in 41% of cases of dupilumab requiring therapeutic escalation.Conclusions Although rare, psoriasis and SpA are adverse events emerging during dupilumab or tralokinumab therapy in patients with AD. Close monitoring and prompt differential diagnosis are essential to optimize patient outcomes.This multicentre retrospective study investigates the occurrence of paradoxical psoriasis and seronegative spondyloarthropathy (SpA) in patients with atopic dermatitis (AD) treated with dupilumab or tralokinumab. Among 6668 patients, these adverse events were infrequent but clinically relevant, with psoriasis observed in 1.3% (dupilumab) and 2.1% (tralokinumab), and SpA in 0.3% and 0.1%, respectively. The findings highlight the need for vigilance and tailored management in patients with AD receiving interleukin-4/13 inhibitors.