Real-World Effectiveness and Safety of Upadacitinib and Abrocitinib in Moderate-to-Severe Atopic Dermatitis: A 52-Week Retrospective Study

<b>Background:</b> Atopic dermatitis (AD) is a chronic pruritic inflammatory disease affecting children and adults. Upadacitinib and abrocitinib are selective Janus kinase 1 inhibitors approved for the treatment of moderate-to-severe AD. Although their efficacy and safety are described in phase 3 clinical trials, real-world data are limited. <b>Objectives:</b> We aimed to evaluate the effectiveness and safety of upadacitinib and abrocitinib treatment in a real-life adult population with moderate-to-severe AD throughout an extended observation period. <b>Methods:</b> This retrospective observational study was conducted by analyzing data from the electronic records of IRCCS Humanitas Research Hospital from January 2023 to December 2024. Patients were administered either upadacitinib (15 or 30 mg) or abrocitinib (100 or 200 mg). Effectiveness was evaluated by using clinician-reported scores (Investigator Global Assessment [IGA] and Eczema Area and Severity Index [EASI]) and patient-reported outcomes (peak pruritus numerical rating scale [PP-NRS]) at weeks 8, 16, 32 and 52. Statistical significance was set at a probability value (<i>p</i>-value) < 0.05. Adverse events were also collected. <b>Results:</b> In total, 129 patients were included in the study, and 84 of them reached 52 weeks. At week 52, the EASI 75, 90, and 100 responses were 88.9%, 70.8%, and 54.2% for upadacitinib, and 100%, 91.7%, and 75% for abrocitinib. An IGA score equal to 0 or 1 at 52 weeks was achieved by 84.7% of patients treated with upadacitinib and 100% of those receiving abrocitinib. A four-point reduction from baseline PP-NRS was reported by 86.1% for upadacitinib and by 83.3% of patients for abrocitinib after one year of follow-up. <b>Conclusions:</b> Our study showed comparable or even higher effectiveness outcomes in terms of EASI 75, EASI 90, and EASI 100 at week 52 compared to phase-3 clinical trials, with no new safety concerns, supporting the real-world effectiveness of abrocitinib and upadacitinib in moderate-to-severe AD.