The purpose of this study is to assess the efficacy and safety of Afimkibart (also known as RO7790121) in participants with moderate to severe atopic dermatitis (AD).

Inclusion Criteria:

• AD diagnosis confirmed by a dermatologist according to the Hanifin/Rajka criteria at least 1 year prior to screening
• Moderate to severe AD
• At least once daily use of an additive-free, bland emollient for at least 7 days prior to the baseline visit and during the study

Exclusion Criteria:

• Evidence of other skin conditions that would interfere with the assessment of AD, including, but not limited to, for example cutaneous T-cell lymphoma, allergic contact dermatitis
• IV, IM, IL, and oral corticosteroids (inhaled, ophthalmic drops, and nasal corticosteroids are allowed) within 4 weeks of the baseline visit and during the study
• Topical treatment for AD including, but not limited to topical corticosteroids, topical calcineurin Inhibitors, topical PDE-4 inhibitors, , prescription moisturizers or moisturizers containing additives such as ceramide, hyaluronic acid, urea or filaggrin within 7 days prior to the baseline visit and during the study
• Any active infection or other active skin diseases that required treatment with parenteral anti-infectives within 4 weeks or oral anti-infective treatment within 2 weeks prior to baseline
• Acquired or congenital immunodeficiency
• Systemic therapies that are also used in the treatment of AD, including, but not limited to methotrexate, cyclosporine, azathioprine, mycophenolate mofetil within 4 weeks of the baseline visit and during the study

For eligible studies, qualified researchers may request access to individual patient level clinical data. See Roche's commitment to transparency of clinical study information here: https://go.roche.com/data\_sharing