Abstract
Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) comprises a spectrum of autoimmune diseases, including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Studies have shown that avacopan and mepolizumab are promising therapeutics for partial or complete replacement of glucocorticoids (GC), with sustained remission while completely weaning off GC. Avacopan inhibits C5aR in the complement pathway, preventing neutrophil migration, while mepolizumab targets IL-5R, reducing eosinophil activity. Additionally, complement inhibition has not only contributed to the recovery of renal function and alleviation of physical symptoms but has also enhanced patients' overall quality of life and mental well-being. This systematic review explores the pathogenesis of AAV, traditional treatments, and the potential of emerging complement and interleukin antagonist therapies such as avacopan and mepolizumab in revolutionizing AAV management.