A Study to Confirm the Efficacy and Safety of Different Dupilumab Dose Regimens in Adults With Atopic Dermatitis (AD)

A Phase 3, Randomized, Double-Blind, Placebo-Controlled Study Investigating the Efficacy and Safety of Multiple Dupilumab Dose Regimens Administered as Monotherapy for Maintaining Treatment Response in Patients With Atopic Dermatitis

The primary objective of the study was to assess the ability of different Dupilumab dose regimens, administered as monotherapy, to maintain the treatment response achieved after 16 weeks of initial treatment with Dupilumab monotherapy compared to placebo.

Key Inclusion Criteria:

1. Must have completed the treatment phase in 1 of the two 16-week initial treatment studies (R668-AD-1334 or R668-AD-1416).

2. Must have achieved at least 1 of the following 2 treatment success criteria:

   Investigator Global Assessment (IGA) = 0 or 1 (clear or almost clear) at week 16 OR Eczema Area and Severity Index >= 75% (EASI-75) (at least 75% reduction in EASI score from baseline to week 16)

3. Must be willing and able to comply with clinic visits and study-related procedures

4. Must provide signed informed consent

5. Must be able to understand and complete study-related questionnaires

Key Exclusion Criteria:

1. Receipt of rescue medication for AD in the initial treatment study
2. Any conditions that require permanent discontinuation of study treatment in either initial treatment study
3. Planned or anticipated major surgical procedure during the participants's participation in this study
4. Pregnant or breastfeeding women, or women planning to become pregnant or breastfeed during this study
5. Women unwilling to use adequate birth control, if of reproductive potential* and sexually active. Adequate birth control is defined as agreement to consistently practice an effective and accepted method of contraception, whenever engaging in heterosexual intercourse, throughout the duration of the study and for 120 days after last dose of study drug. These include hormonal contraceptives, intrauterine device, or double barrier contraception (e.g, condom + diaphragm), or a male partner with documented vasectomy. Additional requirements for acceptable contraception may apply in certain countries, based on local regulations. Investigators in these countries will be notified accordingly in a protocol clarification letter.

(*For females, menopause is defined as at least 12 consecutive months without menses; if in question, a follicle stimulating hormone level of >= 25 milli units per milliliter (mU/mL) must be documented. Hysterectomy, bilateral oophorectomy, or bilateral tubal ligation must be documented, as applicable; if documented, women with these conditions are not required to use additional contraception).