Advances in the treatment of eosinophilic granulomatosis with polyangiitis.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a small-vessel vasculitis associated with anti-neutrophil cytoplasmic antibodies and characterized by blood and tissue eosinophilia, severe respiratory manifestations, and multiorgan involvement. The management of newly diagnosed EGPA still relies on therapeutic strategies that were initially validated for other forms of anti-neutrophil cytoplasmic antibody-associated vasculitis, including microscopic polyangiitis and granulomatosis with polyangiitis. Whereas the long-term prognosis of microscopic polyangiitis and granulomatosis with polyangiitis depends primarily on controlling initial organ involvement and preventing relapses, EGPA is distinguished by chronic involvement of both upper and lower respiratory airways, which often necessitates prolonged glucocorticoid therapy. Data from clinical trials suggest that targeting the IL-5 pathway with mepolizumab or benralizumab can effectively control persistent respiratory symptoms and reduce the need for glucocorticoids, yet the role of these agents in the management of EGPA at the time of diagnosis and in the long term remains to be defined. Emerging retrospective data on therapies targeting other type 2 cytokines (such as IL-4, IL-13 and thymic stromal lymphopoietin) suggest potential benefits for relapsing respiratory symptoms; however, prospective evidence remains limited and safety has yet to be established. This Review discusses the role of these new targeted therapies in the management of EGPA, alongside historical treatments.