Reslizumab in the Treatment of Eosinophilic Granulomatosis With Polyangiitis (EGPA) Study

This study is open-label which means that all subjects will receive the study medication. The study medicine - reslizumab - will be given to the participants in addition to the medicines they are already taking to treat their EGPA such as oral steroids (e.g. prednisone) and medicines that reduce the activity of their immune system (the study doctor will tell the participants which medications these are) - this is what is meant by 'standard of care' and can vary in different countries. Drugs that are sometimes used (i.e., 'standard of care') to reduce the activity of the immune system in EGPA (in addition to oral steroids) include azathioprine, methotrexate, mycophenolate mofetil and cyclophosphamide. Information about how the study drug affects the human body and health will be collected through a number of tests, procedures and questions. The study medicine, reslizumab, will be given to the participants at a dose of 3mg/kg intravenously (within a vein) every four weeks for 28 weeks for a total of 7 treatments. During the treatment phase of this study, a study staff member will call the participants every two weeks to see how they are doing, what medications they are taking, and if they are able to decrease their steroid use. The study is a total of 11 study visits in a 44 week time period. Everyone who takes part in the study will continue to receive his/her existing treatments for EGPA (although the dose of oral steroids may be reduced during the study).