When to start and when to stop primary prophylaxis in patients with severe haemophilia.

Primary prophylactic treatment of patients with severe haemophilia has been shown to reduce the number of bleeding episodes and to minimize the development of arthropathy. However, since the use of clotting factor concentrates is associated with considerable cost and not all patients with severe haemophilia have a severe bleeding phenotype, there is still no consensus about when to start prophylaxis, which dosing regimen to use, and if or when the treatment should be stopped when the patient becomes elderly. Some care providers are also concerned about the use of central venous lines in very young children. Even though most available data indicate that prophylaxis should be started during the first years of life, it may be possible to adjust the dose and dose interval depending on the bleeding pattern. The use of an individualized prophylactic regimen may also improve cost-effectiveness and make the use of this treatment modality more feasible. Studies to further address this issue are warranted.