['dermatitis, atopic']
['dupilumab', 'placebo (for dupilumab)']

        Inclusion Criteria:

          1. Male or female, 18 years or older

          2. Chronic AD (according to American Academy of Dermatology Consensus Criteria
             Eichenfield 2014) that has been present for at least 3 years before the screening
             visit;

          3. Eczema Area and Severity Index (EASI) Score ≥16 at the screening and baseline visits;

          4. Investigator's Global Assessment (IGA) Score ≥3 (on the 0 to 4 IGA scale, in which 3
             is moderate and 4 is severe) at the screening and baseline visits;

          5. ≥10% body surface area (BSA) of AD involvement at the screening and baseline visits;

          6. Documented recent history (within 6 months before the screening visit) of inadequate
             response to treatment with topical medications or for whom topical treatments are
             otherwise medically inadvisable (e.g, because of important side effects or safety
             risks).

        Exclusion Criteria:

          1. Participation in a prior Dupilumab clinical study;

          2. Treatment with an investigational drug within 8 weeks or within 5 half-lives (if
             known), whichever was longer, before the baseline visit;

          3. Having used any of the following treatments within 4 weeks before the baseline visit,
             or any condition that, in the opinion of the investigator, was likely to require such
             treatment(s) during the first 4 weeks of study treatment:

               -  Immunosuppressive/ immunomodulating drugs (e.g, systemic corticosteroids,
                  cyclosporine, mycophenolate-mofetil, IFN-γ, Janus kinase inhibitors,
                  azathioprine, methotrexate, etc.);

               -  Phototherapy for AD

          4. Treatment with topical corticosteroids (TCS) or topical calcineurin inhibitors (TCI)
             within 1 week before the baseline visit;

          5. Treatment with biologics as follows:

               -  Any cell-depleting agents including but not limited to rituximab: within 6 months
                  before the baseline visit, or until lymphocyte count returns to normal, whichever
                  was longer

               -  Other biologics: within 5 half-lives (if known) or 16 weeks prior to baseline
                  visit, whichever was longer

          6. Regular use (more than 2 visits per week) of a tanning booth/ parlor within 4 weeks of
             the screening visit;

          7. Planned or anticipated use of any prohibited medications and procedures during study
             treatment;

          8. Treatment with a live (attenuated) vaccine within 12 weeks before the baseline visit;

          9. Active chronic or acute infection requiring treatment with systemic antibiotics,
             antivirals, antiparasitics, antiprotozoals, or antifungals within 2 weeks before the
             baseline visit, or superficial skin infections within 1 week before the baseline
             visit. NOTE: Participants might be rescreened after infection resolves;

         10. Known or suspected history of immunosuppression, including history of invasive
             opportunistic infections (e.g, tuberculosis [TB], histoplasmosis, listeriosis,
             coccidioidomycosis, pneumocystosis, aspergillosis) despite infection resolution: or
             unusually frequent, recurrent, or prolonged infections, per investigator judgment;

         11. History of human immunodeficiency virus (HIV) infection or positive HIV serology at
             screening;

         12. Positive with hepatitis B surface antigen (HBsAg) or hepatitis C antibody at the
             screening visit;

         13. Participant was a member of the investigational team or his/her immediate family;

         14. Pregnant or breastfeeding women, or women planning to become pregnant or breastfeed
             during the study;

         15. Women unwilling to use adequate birth control, if of reproductive potential and
             sexually active.

        Note: The information listed above is not intended to contain all considerations relevant
        to a participant's potential participation in this clinical trial therefore not all
        inclusion/ exclusion criteria are listed.
      