This clinical trial is focused on studying a disease called ANCA-associated vasculitis, which is a condition where the body’s immune system mistakenly attacks its own blood vessels, leading to inflammation. In this study, the specific type of ANCA-associated vasculitis being examined involves severe bleeding in the lungs, known as pulmonary hemorrhage. The treatment being tested is a medication called Idefirix, which contains an active substance named imlifidase. This medication is given through an intravenous infusion, meaning it is administered directly into the bloodstream.
The purpose of the study is to evaluate how effective Idefirix is when used alongside the standard care for patients with severe ANCA-associated vasculitis and lung bleeding. Participants in the study will receive either Idefirix or a placebo, in addition to the usual treatments for their condition. The study will monitor how quickly the levels of ANCA antibodies in the blood decrease after treatment, as well as other health outcomes such as lung and kidney function, and overall safety.
Throughout the study, researchers will observe participants for any changes in their condition, including improvements in lung function and any potential side effects. The study aims to provide valuable information on the potential benefits and safety of using Idefirix in treating this serious form of vasculitis. The trial is expected to continue until mid-2026, with recruitment of participants starting in 2024.



Germany