This clinical trial is focused on studying atopic dermatitis, a skin condition that causes red, itchy, and inflamed skin. The trial will evaluate a new treatment called LEO138559, which is a solution for injection. This treatment is a type of protein known as a humanised IgG1 monoclonal antibody that targets a specific part of the immune system involved in atopic dermatitis. The study will compare the effects of different doses of LEO138559 with a placebo to understand its safety and effectiveness in treating moderate-to-severe atopic dermatitis in adults.

The purpose of the study is to find out how well LEO138559 works and how safe it is for people with moderate-to-severe atopic dermatitis. Participants in the study will receive injections of either LEO138559 or a placebo. The study will last for 16 weeks, during which participants will be monitored to see how their skin condition changes over time. The main focus will be on the percentage change in the severity of the skin condition from the start of the study to the end of the 16 weeks.

Throughout the study, researchers will also keep track of any side effects that participants might experience. This information will help determine the safety of LEO138559 and its potential as a treatment option for atopic dermatitis. The study aims to provide valuable insights into managing this skin condition and improving the quality of life for those affected by it.