Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired disorder of complement dysregulation, predisposing patients to complications of intravascular hemolysis, thrombophilia, and marrow failure, with a high risk of mortality without treatment. Allogeneic stem cell transplantation is the only current cure but is typically reserved for marrow failure-predominant disease or when targeted therapies are not available. Terminal complement inhibition with eculizumab has significantly altered management and outcomes for patients with PNH, and the last several years have seen the development and approval of many new complement inhibitors with different molecular targets. Newer inhibitors may also provide options for extended time between doses, for self-administration, and for management of iatrogenic extravascular hemolysis, which can occur secondary to C5 inhibition. This essay reviews the various therapeutic options potentially available to PNH patients, the pros and cons of each treatment, considerations regarding the monitoring of side effects, and the possible complications, as well as breakthrough hemolysis and an approach to shared decision-making.

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