The purpose of this study is to evaluate the efficacy and safety of rapcabtagene autoleucel versus comparator in participants with severe active Granulomatosis with Polyangiitis (GPA) or Microscopic Polyangiitis (MPA)

This is a Phase 2, randomized, assessor-blinded active controlled study. This study comprises two cohorts:

• A lead-in cohort enrolling participants to receive rapcabtagene autoleucel
• A randomized cohort with participants receiving either rapcabtagene autoleucel or comparator.

After end of study (EOS), participants who received rapcabtagene autoleucel infusion will enter a long-term follow-up (LTFU) period lasting up to 15 years after rapcabtagene autoleucel infusion. This LTFU will be described in a separate study protocol.

Key inclusion criteria:

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 exclusion criteria:

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 diseases 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. Inadequate organ function

Novartis is committed to sharing access to patient-level data and supporting clinical documents from eligible studies with qualified external researchers. Requests are reviewed and approved by an independent review panel on the basis of scientific merit. All data provided are anonymized to protect the privacy of patients who have participated in the trial in line with applicable laws and regulations.

This trial data availability is according to the criteria and process described on www.clinicalstudydatarequest.com

The study investigator and the participant will be unblinded to the study treatment. A blinded assessor will perform the efficacy assessments to minimize bias in data collection.