Emerging targeted therapies in ANCA-associated vasculitis.

Drug development in ANCA-associated vasculitis has aimed to improve on the success of the B cell depleting monoclonal antibody rituximab and exploit better understanding of inflammatory pathways. More potent B cell depletion strategies are being tested as are B cell cytokine inhibitors. The involvement of the complement system in pathogenesis is more complicated than previously thought and extends beyond C5a dysregulation and its inhibition with avacopan, broader complement inhibitors and complement regulatory agonists are potential newer therapies. Other approaches have aimed to directly control neutrophil activation and to try to modulate tissue repair and fibrosis that occurs following vasculitis inflammation.