Real-world experience with using rIX-FP for treating severe hemophilia B in a Chinese population: A case series from a single hospital

Hemophilia B is a rare, recessive X-linked disorder caused by mutations in the F9 gene, causing coagulation factor IX (FIX) deficiencies or absence. This study evaluated the real-world efficacy of rIX-FP, a long-acting recombinant FIX fused with human albumin, in five patients with severe hemophilia B at a single center in Taiwan. Patients who transitioned from biweekly standard FIX therapies to weekly rIX-FP demonstrated improved bleeding control (annual bleeding rates ranging from 0 to 11.4) with improved joint health and quality of life. Prophylactic regimens were tailored to the patients’ lifestyles, from a construction worker requiring high FIX levels to an office administrator. Despite some challenges with self-reported bleeding episodes, particularly among patients with cognitive impairments, the overall outcomes highlight the clinical benefits of rIX-FP in managing severe hemophilia B. This study contributes valuable real-world data supporting the use of rIX-FP in routine clinical practice, particularly among the Chinese population.