C5 and neuromyelitis optica: PNH and aHUS, and to some extent AAV, have been success stories where complement inhibition has demonstrated efficacy and has emerged as the novel SoC (23–26).The C5 inhibitors eculizumab and ravulizumab (approved for PNH, aHUS, myasthenia gravis, and neuromyelitis optica spectrum disorder) are monoclonal antibodies that block the cleavage of the terminal complement protein C5 to C5a and C5b through C5 convertase, thereby preventing the formation of MAC, regardless of the initial pathway.