PREP-ANCA - Comparison of a strategy based on clinic-biological surveillance versus pre-emptive treatment with rituximab in the event of ANCA (anti-neutrophil cytoplasm antibodies) repositivation in patients with granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA)

This study is designed to help people living with two uncommon conditions called granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA). These conditions cause inflammation in the body's small blood vessels, which can affect many organs. After treatment, patients often go into remission, meaning their symptoms improve or disappear. However, there's always a risk the condition might flare up again.

The main question this study wants to answer is: What's the best way to prevent a relapse (when the condition comes back or gets worse) once a patient's ANCA levels start to rise again? ANCA stands for anti-neutrophil cytoplasm antibodies, which are special markers in the blood. When these levels go up, it can sometimes be an early warning sign that the condition might be returning. The study is comparing two different ways to handle this:

One group of patients will be closely monitored by their doctors, and treatment will only be given if their symptoms or other tests show a definite flare-up. The other group will receive an earlier preventative treatment with a medicine called rituximab (also known as Truxima) if their ANCA levels increase, even before they have clear symptoms. The researchers will then compare both groups over two years to see which approach helps patients stay healthier for longer without their condition returning. They will also look at other important things like side effects, quality of life, and how much steroid medication is needed.