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

Study duration for each participant will be approximately 112 weeks, including:

• Screening period: Up to 4 weeks (Day -28 to Day -1) from signing the informed consent.
• Open-label dupilumab treatment period: 104 weeks (from Day 1/Week 0 to Week 104).
• Follow-up period: 4 weeks (safety follow-up phone visit at 4 weeks after the EoT visit).

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.