The IL-5 inhibitor mepolizumab combined with glucocorticoids is recommended to induce remission in patients with relapsed and refractory EGPA without organ damage or life-threatening manifestations, and can also be used for maintenance therapy, but evidence-based medical data are currently lacking to demonstrate the effectiveness of mepolizumab in patients with EGPA with CNS involvement. Here, IL5 is linked to eosinophilic granulomatosis with polyangiitis.