A Study of Long-term Effect of Dupilumab on Skin Barrier Function in Pediatric Participants With Atopic Dermatitis

Inclusion Criteria: Age * For new participants: ≥6 to \<12 years of age (inclusive), at the time of signing the informed consent. * For former PELISTAD participants: ≥6 to \<15 years of age at the time of signing the informed consent. Type of participant and disease characteristics * With AD diagnosis according to Hanifin and Rajka criteria at least 1 year before screening. * Applicable to new participants only: Validated Investigator Global Assessment for AD (vIGA AD™) score of ≥3 (for US and Canada participants) or ≥4 (for UK participants) at screening (on the 0 to 4 scale) depending on the approved vIGA-AD™ label indication in the country. * Applicable to new participants only: Have active lesions on the upper limbs or lower limbs (including trunk, if needed), with severity for lesion erythema or edema/papulation ≥2 at screening on the 0 to 3 scale of the ISS. * Applicable to all participants: Should have a non-lesional (normal looking) skin area 4 cm from the edge of the lesional area. If unable to identify non-lesional skin 4 cm from the lesional area, it is acceptable to identify normal looking skin as close to the lesion as possible. * Willing to refrain from applying any topical medications on the target assessment areas (including lesional and non-lesional) throughout the study until EoS unless necessary to alleviate intolerable symptoms. * Willing and able to comply with all clinic visits and study-related procedures. Weight * Body weight ≥15 kg at screening. Exclusion Criteria: Medical conditions * Skin conditions other than AD that can confound assessments in the area of TEWL assessments in the opinion of the Investigator (ie, skin atrophy, ichthyosis, tinea infection, contact dermatitis). * Cracked, crusted, oozing, or bleeding AD lesions in the designated lesional assessment area leaving insufficient skin that is adequate for TEWL assessments. * Hypersensitivity to the active substance or to any of the excipients of dupilumab. * Ocular disorder that in the opinion of the Investigator could adversely affect the individual's risk for study participation. * Severe concomitant illness(es) that, in the Investigator's judgment, would adversely affect the participant's participation in the study. * History of hypersensitivity reaction to skin tape or adhesives used in tape strip discs. Prior/concomitant therapy * Treatment with any investigational medication other than dupilumab within 16 weeks or within 5 half-lives (if known) prior to Day 1, whichever is longer. * Systemic AD treatment, cyclosporine A (CsA), systemic corticosteroids, azathioprine (AZA), methotrexate (MTX), mycophenolate mofetil (MMF), or Janus kinase (JAK) inhibitors or phototherapy within 4 weeks of baseline. * Topical AD treatment within 1 week of baseline. Face and neck may be treated with topical steroids during the washout period if approved by the Investigator. * Participants who received a live vaccine within 4 weeks of baseline. Prior/concurrent clinical study experience * Current participation in another investigational or interventional clinical study. The above information is not intended to contain all considerations relevant to a potential participation in a clinical trial.