Study of Salvage Therapy to Treat Patients With Granulomatosis With Polyangiitis

This clinical study is investigating "Study of Salvage Therapy to Treat Patients With Granulomatosis With Polyangiitis". Researchers are looking for volunteers to help improve understanding and treatments in this area. You may be eligible if: - You are at least 18 Years - Aged 18 years or older - Active clinical manifestations attributable to GPA - An inadequate response to previous standard of care therapy including either : - A combination of glucocorticoids plus cyclophosphamide - AND /OR a combination of glucocorticoids plus rituximab You may NOT be eligible if: - An allergy or hypersensitivity to monoclonal antibodies or either of the study drugs (rituximab, abatacept or tocilizumab) or to their excipients - A previous treatment with a combination of rituximab plus a cDMARD, with tofacitinib, or with tocilizumab - Patients with vasculitis in remission - Patients with symptoms attributable to chronic and non-active GPA - Patients with severe cardiac failure defined as class IV in New York Heart Association - Patients with acute infections or chronic active infections (including HIV, HBV or HCV) Talk to your doctor to see if this trial is right for you.