Administration of exogenous FH could be useful also in other conditions associated with alternative pathway dysregulation ranging from the rare hematological disease paroxysmal nocturnal hemoglobinuria, to the common blinding disease age-related macular degeneration (3) Considering the human and economic cost of plasma-derived products and the shortage of blood and its derivatives, the use of plasma waste fractions for the therapy of orphan rare diseases will represent an ethical and essential approach. The gene discussed is FH; the disease is paroxysmal nocturnal hemoglobinuria.