Pharmacokinetics, Immunogenicity and Safety of Subcutaneous Dupilumab and Berahyaluronidase Alfa (ALT-B4) Coformulation (EXTENSA)

Inclusion Criteria:

• Participant must be ≥12 years of age at the time of signing the informed consent.

• Participants with chronic AD, (according to American Academy of Dermatology Consensus Criteria, that has been present for at least 12 months before the screening visit.

• Participants with ≥10% body surface area (BSA) of AD involvement at the screening and baseline visits.

• Participant's AD must be graded as Eczema Area and Severity Index (EASI) score ≥16 at the screening and baseline visits.

• Validated Investigator Global Assessment for Atopic Dermatitis (v-IGA) ≥3 at the screening and baseline visits.

• Worst-Itch Numerical Rating Scale (WI-NRS) weekly average score ≥4 in the 7 days before randomization.

• 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 (eg, because of important side effects or safety risks).

  *Inadequate response to topical therapy is defined as persistent moderate-to-severe AD (EASI ≥16, vIGA-AD ≥3, BSA ≥10%) despite ≥4 weeks of optimized topical anti-inflammatory treatment (medium/high potency corticosteroids ± calcineurin inhibitors), or documented intolerance/contraindication to such therapies.

• For adolescents (≥12 and <18 years old) only, body weight ≥60 kg.

Exclusion Criteria:

• Any history or presence of severe concomitant illness(es) that, in the Investigator's judgment, would adversely affect the participant's participation in the study. Examples include, but are not limited to participants with short life expectancy, participants with uncontrolled diabetes (hemoglobin A1c ≥9%), participants with cardiovascular conditions (e.g, cardiomyopathy, thromboembolism, Class III or IV cardiac failure according to the New York Heart Association classification), severe hematological conditions (e.g. hyperviscosity), severe renal conditions (e.g, participants on dialysis), hepato-biliary conditions (e.g, Child-Pugh class B or C), neurological conditions (e.g, demyelinating diseases), active major autoimmune diseases (e.g, lupus, inflammatory bowel disease, rheumatoid arthritis, etc), other severe endocrinological, gastrointestinal, metabolic, pulmonary, or lymphatic diseases. The specific justification for participants excluded under this criterion will be noted in study documents (chart notes, case report forms [CRF], etc).
• 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 may be rescreened after infection resolves.
• 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, suggesting immunocompromised status per Investigator judgment.
• Presence of any skin comorbidities other than AD that, in the opinion of the Investigator, may interfere with the assessment of the study outcomes. For example: scabies, insect bite, folliculitis, lymphomatoid papulosis, chronic actinic dermatitis, dermatitis herpetiformis, sporotrichosis, bullous disease, or others.
• History of malignancy within 5 years before the screening visit, except completely treated in situ carcinoma of the cervix, completely treated and resolved non-metastatic squamous or basal cell carcinoma of the skin.
• Diagnosed with, suspected of, or at high risk for endoparasitic infection, and/or use of antiparasitic drugs within 2 weeks before Screening (Visit 1) or during the Screening period.
• Previously treated with marketed dupilumab or having received dupilumab in a prior dupilumab clinical study.

The above information is not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.