2a Study to Assess the Efficacy and Safety of REGN3500 Monotherapy and Combination of REGN3500 Plus Dupilumab in Adult Patients With Moderate-to-Severe Atopic Dermatitis

Key Inclusion Criteria:

1. 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

2. Eczema Area and Severity Index (EASI) score ≥16 at the screening and baseline visits

3. ≥10% Body surface area (BSA) of AD involvement at the screening and baseline visits

4. Documented recent history (within 6 months before the screening visit) of inadequate
response to topical AD medication(s) or for whom topical treatments are medically
inadvisable

Key Exclusion Criteria:

1. Prior participation in a REGN3500 (anti-Interleukin (IL)-33) or dupilumab
(anti-IL-4Rα) clinical study; past treatment with or current treatment with dupilumab

2. Active chronic or acute infection requiring treatment with systemic antibiotics,
antivirals, antiparasitics, antiprotozoals, or antifungals 2 weeks before the baseline
visit, or superficial skin infections within 1 week before the baseline visit

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

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

5. Positive with hepatitis B surface antigen (HBsAg), hepatitis B core antibody (HBcAb),
or hepatitis C virus antibody (HCV Ab) at the screening visit

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

Note: Other protocol defined Inclusion/Exclusion Criteria apply