Efficacy, Safety, and Pharmacokinetic Profiles of REGN3500 Administered to Adult Patients With Moderate-to-Severe Atopic Dermatitis

A Phase 2b, Randomized, Double-Blind, Placebo-Controlled, Parallel-Group, Dose-Ranging Study Investigating the Efficacy, Safety, and Pharmacokinetic Profiles of REGN3500 Administered to Adult Patients With Moderate-to- Severe Atopic Dermatitis

The primary objective of the study is to assess the efficacy of REGN3500 monotherapy in Atopic dermatitis (AD), as well as understand the dose-response relationship, compared with placebo treatment, in adult patients with moderate-to-severe AD.

Secondary objectives are to:

• Assess the safety and tolerability of subcutaneous (SC) doses of REGN3500 monotherapy in adult patients with moderate-to-severe AD
• Assess the Pharmacokinetics (PK) of REGN3500 in adult patients with moderate-to-severe AD
• Assess the immunogenicity of REGN3500 in adult patients with moderate-to-severe AD

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. IGA score ≥3 (on the 0 to 4 IGA scale, in which 3 is moderate and 4 is severe) at screening and baseline visits
4. ≥10% Body surface area (BSA) of AD involvement at the screening and baseline visits
5. 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. Participation in a prior anti-Interleukin (IL)-33 medication clinical study

2. Treatment with an investigational drug within 8 weeks or within 5 half-lives (if known), whichever is 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, is likely to require such treatment(s) during the first 4 weeks of study treatment:

   1. Immunosuppressive/immunomodulating drugs (eg, systemic corticosteroids, cyclosporine, mycophenolate-mofetil, Interferon-gamma (IFN-γ), Janus kinase inhibitors, azathioprine, methotrexate, etc)
   2. Phototherapy for AD

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

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

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

7. Known or suspected history of immunosuppression

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

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

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

Note: Other protocol defined Inclusion/Exclusion Criteria apply