[Antibody therapy for paroxysmal nocturnal hemoglobinuria]

Treatment with eculizumab (Soliris^®), a humanized anti-C5 monoclonal antibody improves the quality of life of patients with paroxysmal nocturnal hemoglobinuria (PNH), remarkably reduces hemolysis, improves symptoms associated with hemolysis, and prevents thrombosis. Because eculizumab therapy is not a curative treatment, it is necessary to continue infusion every two weeks, which has been an issue from the viewpoint of convenience. In recent years, an improved version of eculizumab, ravulizumab (Ultomiris^®), which relies on the technology of recycling antibodies has been developed and can be administered every 8 weeks. Crovalimab (SKY59), which can be administered subcutaneously every four weeks, is also under development, and therefore, the convenience for patients with PNH is improving. However, many issues still persist, and several new anti-complement drugs are currently under development. Hopefully, a better drug will be developed by thorough examination of what drug is best for the patient by considering not only its efficacy and safety but also its convenience.