Dupilumab efficacy in children aged 6 months to younger than 6 years with moderate-to-severe atopic dermatitis and clinical characteristics of early super-responders

Abstract Background To evaluate the efficacy of dupilumab in treating moderate-to-severe atopic dermatitis (AD) in children aged 6 months to 6 years and to investigate the clinical characteristics influencing early super-responders（eSR). Methods This study adopted a prospective design and enrolled pediatric patients with moderate-to-severe AD who were treated at the Department of Dermatology, General Hospital of Ningxia Medical University, from January 2023 to March 2025. In accordance with the patients’ age and body weight, a subcutaneous injection of dupilumab (200–300 mg) was administered every 4 weeks. At baseline, week 4, week 12, and week 16 of treatment, the efficacy of dupilumab and the family quality of life were evaluated using the following tools: the Eczema Area and Severity Index (EASI), Investigator’s Global Assessment (IGA), Peak Pruritus Numeric Rating Scale (PP-NRS), Children’s Dermatology Life Quality Index (CDLQI)/Infant’s Dermatology Life Quality Index (IDQoL), and Dermatitis Family Impact (DFI). Improvements in comorbid conditions were assessed using the Rhinoconjunctivitis Control Assessment Test (RCAT), Child Asthma Control Test (C-ACT), and Oral Food Challenge (OFC). Moreover, adverse events that occurred during the treatment period were recorded systematically. The proportions of patients who achieved EASI75 (≥75% improvement in EASI score from baseline), a ≥4-point reduction in PP-NRS, and a ≥4-point improvement in CDLQI / IDQoL concurrently at week 4, as well as those who met both EASI75 and IGA 0/1(clear/almost clear) at week 16, were documented. Linear mixed models were used to analyze changes in clinical scores at different time points before and after dupilumab treatment, and logistic regression was applied to identify factors influencing eSR to dupilumab treatment. Results A total of 50 children with moderate to severe AD, including 21 males (42.00%) and 29 females (58.00%), aged 4.24±1.81, were included in this study. Clinical scores related to skin lesions and pruritus were significantly lower at weeks 4, 12, and 16 postdupilumab treatment than at baseline ( P < 0.001). At week 4, 40.00% (20/50) of patients achieved the primary efficacy endpoints. By week 16, 87.10% (27/31) and 90.32% (28/31) of patients had EASI75 and an IGA 0/1, respectively. The proportion of patients with severe/moderate DFI scores decreased markedly from 100% at baseline to 9.68% ( P < 0.001). Notably, the prevalence of recurrent upper respiratory tract infections decreased significantly (P = 0.017), while the improvement rates for allergic rhinitis and food allergies reached 84.21% ( P < 0.001) and 84.61% ( P < 0.001), respectively. Multivariate logistic regression revealed that a high absolute basophil count (OR = 0.104, 95% CI = 0.021-0.506, P = 0.005) and the presence of allergic rhinitis (OR = 0.223, 95% CI = 0.055-0.896, P = 0.035) were independent predictors of eSR. Receiver operating characteristic (ROC) curve analysis demonstrated high predictive accuracy (AUC = 0.773; P = 0.001), indicating that a baseline absolute basophil count less than 0.035×109/L was associated with a better eSR to dupilumab. No serious adverse events were observed during treatment. Conclusion Dupilumab demonstrates significant efficacy and a favorable safety profile in the treatment of moderate-to-severe atopic dermatitis in children aged 6 months to 6 years. During treatment, patients presented alleviated allergic comorbidities, decreased incidence of recurrent upper respiratory tract infections, and improved quality of life for children and their families. Elevated absolute basophil count in peripheral blood and the presence of allergic rhinitis were independent predictors of eSR to dupilumab in children with AD.