Clinical and inflammatory determinants of successful abrocitinib dose reduction in atopic dermatitis: a real-world cohort study with implications for treatment optimization

BACKGROUND: Abrocitinib, a selective Janus kinase 1 inhibitor, is an effective therapy for moderate-to-severe atopic dermatitis (AD). However, evidence guiding dose reduction during long-term maintenance in real-world practice remains limited, and determinants of successful dose tapering are unclear. OBJECTIVE: To evaluate the feasibility of abrocitinib dose reduction and identify clinical and immunological features associated with tapering. METHODS: In this prospective real-world study, 66 adults with moderate-to-severe AD received standard-dose abrocitinib for 12 weeks, followed by individualized dose adjustment based on disease control. Clinical outcomes and serum cytokine profiles were assessed longitudinally to characterize treatment responses and immunological correlates of dose reduction. RESULTS: Baseline disease severity was comparable between groups defined by dose-adjustment outcomes. Patients requiring dose maintenance or escalation had a longer disease duration and higher prevalence of atopic comorbidities and family history, whereas those achieving dose reduction tended to be older. By Week 12, the dose-reduction group achieved significantly lower Eczema Area and Severity Index scores, pruritus numerical rating scale scores and eosinophil counts. These differences persisted during long-term follow-up despite dose reduction. Cytokine analyses demonstrated significantly lower IL-13 levels at Week 12, with consistent trends towards reduced inflammatory activity during maintenance therapy. CONCLUSIONS: Successful abrocitinib dose reduction appears to occur in a clinically distinct subgroup characterized by shorter disease duration, lower atopic burden and deeper early treatment responses. Patients achieving dose tapering exhibited a more quiescent inflammatory profile. These findings support an individualized treatment-optimization strategy aimed at maintaining long-term disease control with the minimal effective dose.