A Study of Long-term Effect of Dupilumab on Skin Barrier Function in Pediatric Participants With Atopic Dermatitis (PELISTAD-EX2)

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 <14 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: Investigator Global Assessment score of ≥3 (for US participants) or IGA ≥4 (for EU participants) at screening (on the 0 to 4 scale) depending on approved IGA 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 new participants only: 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 desquamme 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.