Dupilumab-PEdiatric Skin Barrier Function and LIpidomics STudy in Patients With Atopic Dermatitis

Primary Objective: \- Evaluate changes in skin barrier function with transepidermal water loss (TEWL) assessed after skin tape stripping (STS) in predefined lesional skin in pediatric participants with moderate to severe atopic dermatitis (AD) treated with dupilumab. Secondary Objectives: * Evaluate changes in skin barrier function with TEWL assessed after STS in predefined lesional and non-lesional skin in pediatric participants with moderate to severe AD treated with dupilumab in reference to normal skin of healthy volunteers. * Evaluate time course of change in skin barrier function with TEWL assessed before and after STS in predefined lesional and non-lesional skin in pediatric participants with moderate to severe AD during dupilumab treatment phase and follow-up period in reference to normal skin of healthy volunteers.