This clinical trial is focused on studying atopic dermatitis, a condition that causes the skin to become red, itchy, and inflamed. The trial will evaluate the effectiveness and safety of a medication called tralokinumab, which is used in combination with topical corticosteroids. Topical corticosteroids are creams or ointments applied to the skin to reduce inflammation and itching. The study will involve children aged 2 to under 12 years and infants aged 6 months to under 2 years who have moderate-to-severe atopic dermatitis.

The purpose of the study is to determine if tralokinumab combined with topical corticosteroids provides better control of the skin symptoms of atopic dermatitis compared to a placebo combined with topical corticosteroids. The trial will also explore how this treatment affects symptoms like itching and the overall impact on the quality of life for both the children and their caregivers. Additionally, the study will look into how the treatment influences skin colonization by a common bacteria called Staphylococcus aureus and the composition of lipids in the outer layer of the skin, which is an indirect measure of skin barrier function.

Participants in the study will receive either the active treatment or a placebo, which is a substance with no active medication, for a period of up to 150 days. The trial is designed to be double-blind for children, meaning neither the participants nor the researchers will know who is receiving the active treatment or the placebo. For infants, the trial will be open-label, meaning all participants will receive the active treatment. The study aims to provide valuable information on the potential benefits of tralokinumab for young patients with atopic dermatitis.