Patienter, der vides at have omfattende deletionsmutationer i faktor IX genet, bør observeres tæt for tegn og symptomer på akutte overfølsomhedsreaktioner specielt i de tidlige faser af førstegangseksposition for produktet.
Patients known to have major deletion mutations of the factor IX gene should be observed closely for signs and symptoms of acute hypersensitivity reactions, particularly during the early phases of initial exposure to product.