Complement in ANCA vasculitis, insights on pathophysiology and targeted therapies

Antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) is a debilitating disease with the potential to cause significant morbidity and mortality if not treated. The pathogenesis of this disease is not understood, though emerging evidence suggests that alternative complement pathway system is involved. C5a, mediates several pro-inflammatory effects through its receptor C5aR. Avacopan, targets C5a by preventing it from binding to its receptor C5aR. Complement dysregulation, imbalance between regulatory activity of Factor H and stimulation by Factor H related proteins, has been identified as a new mechanism of disease.