Aplastic Anaemia-Associated PNH Through Successive Therapeutic Eras: From Persistent Extravascular Haemolysis to Complete Haematological Response

Background and Clinical Relevance: C5 inhibitors effectively control intravascular haemolysis (IVH) in paroxysmal nocturnal haemoglobinuria (PNH), but persistent extravascular haemolysis (EVH) may result in ongoing anaemia and transfusion dependence. Iptacopan, an oral complement factor B inhibitor, targets both mechanisms of haemolysis. Case Presentation: We report the 26-year clinical course of a female patient who developed PNH following severe aplastic anaemia. Despite long-term treatment with eculizumab and subsequently ravulizumab, she remained transfusion-dependent due to persistent EVH. The clinical course included three pregnancies, with successful delivery during the third following intensified eculizumab treatment and multidisciplinary management. Switching to iptacopan in 2024 resulted in normalization of haemoglobin, reticulocyte counts and lactate dehydrogenase levels, and complete transfusion independence. Conclusions: This case illustrates the evolving clinical and therapeutic challenges of aplastic anaemia-associated PNH over 26 years. It highlights the limitations of long-term C5 inhibition in controlling EVH and the potential of proximal complement inhibition to achieve sustained haematological recovery and transfusion independence.