Eculizumab safety is substantiated in numerous studies as well as almost two decades of case studies for its four other FDA indications (AchR + generalized myasthenia gravis [6], atypical hemolytic uremic syndrome [7], paroxysmal nocturnal hemoglobinuria [8], and anti-AQP4 neuromyelitis optica [9]). The gene discussed is AQP4; the disease is paroxysmal nocturnal hemoglobinuria.