Phase 2 Study Evaluating Rapcabtagene Autoleucel in Participants With Severe Active GPA or MPA

Key Who May Qualify: 1. Men and women, aged ≥18 and ≤ 75 years with a diagnosis of GPA or MPA according to the American College of Rheumatology/ European League Against Rheumatism 2022 (ACR/EULAR 2022) classification criteria 2. Positive test for ANCA-autoantibodies 3. GPA and MPA participants with severe active disease Key Who Should NOT Join This Trial: 1. Any condition that could prevent a complete washout of medications or could otherwise make the participant ineligible for anti-CD19 CAR-T therapy and further participation in the study 2. Hypersensitivity and/or contraindications to any product to be given to the participant as part of the study protocol 3. Other systemic autoimmune conditions (where your immune system attacks your own body)s requiring therapy 4. Any medical conditions that are not related to GPA/MPA that would jeopardize the ability of the participant to tolerate CD19 CAR-T cell therapy 5. Inyour organs (liver, kidneys, etc.) are working well enough based on blood tests Always talk to your doctor about whether this trial is right for you.