The accepted therapeutic strategy for treating paroxysmal nocturnal hemoglobinuria (PNH) has drastically changed since eculizumab was introduced in 2010 in Japan. Its clinical impact has paved way for the new area of anti-complement therapy, and it has sparked further research and development of anti-complement drugs. The long-term safety and efficacy of eculizumab was established in clinical settings by analyzing post-marketing surveillance that is mandatory in Japan and in clinical trial settings. However, new clinical complications such as resistance to eculizumab, breakthrough hemolysis, extravascular hemolysis, and invasive meningococcal disease (IMD) have emerged after the introduction of eculizumab. Therefore, it is important to strategize effective ways to tackle these issues occurring during eculizumab treatment. In Japan, it is an urgent priority to reach a consensus for managing IMD in patients treated with eculizumab and for establishing protocols for prophylaxis to prevent meningococcal infection.
Keywords: Eculizumab; Invasive meningococcal disease; Paroxysmal nocturnal hemoglobinuria; Therapeutic strategy.