Safety, Pharmacokinetics and Efficacy of Dupilumab in Patients ≥6 Months to <6 Years With Moderate-to-Severe Atopic Dermatitis (Liberty AD PRESCHOOL)

Key Inclusion Criteria

   - Diagnosis of atopic dermatitis (AD) according to the American Academy of Dermatology
   consensus criteria at the screening visit

   - Participants with documented recent history (within 6 months before the screening
   visit) of inadequate response to topical AD medication(s)

   - IGA score at screening and baseline visits

   - part A: IGA = 4

   - part B: IGA ≥3

   - EASI score at screening and baseline visits

   - part A: EASI ≥21

   - part B: EASI ≥16

   - Body Surface Area (BSA) involvement at screening and baseline visits

   - part A: ≥15%

   - part B: ≥10%

   - At least 11 (of a total of 14*) applications of a topical emollient (moisturizer)
   during the 7 consecutive days immediately before the baseline visit (not including the
   day of randomization) (for part B of the study only)

   - Baseline worst scratch/itch score weekly average score for maximum scratch/itch
   intensity ≥4 (for part B of the study only)

   - At least 11 (of a total of 14) daily applications of low potency TCS during the 2-week
   TCS standardization period (beginning on day -14) leading up to the baseline visit
   (for part B of the study only).

Key Exclusion Criteria

   - Prior treatment with dupilumab

   - History of important side effects of low potency topical corticosteroids (only
   applicable for part B of the study)

   - Having used immunosuppressive/immunomodulating drugs within 4 weeks before the
   baseline visit

   - Treatment with a live (attenuated) vaccine within 4 weeks before the baseline visit

   - Active chronic or acute infection requiring treatment with systemic antibiotics,
   antivirals, antiprotozoals, or antifungals within 2 weeks before the baseline visit.

   - Known or suspected immunodeficiency, known history of human immunodeficiency virus
   (HIV) infection or HIV seropositivity at the screening visit, established diagnosis of
   HBV infection or HBV seropositivity at screening, established diagnosis of HCV
   infection or HCV seropositivity at screening

   - History of malignancy at any time before the baseline visit

   - Diagnosed active endoparasitic infections or at high risk of these infections

   - Severe concomitant illness(es) that, in the investigator's judgment, would adversely
   affect the patient's participation in the study

   - Body weight <5 kg or ≥30 kg at baseline (only applicable part B of the study)

Note: Other protocol defined Inclusion/ Exclusion criteria apply