Gene therapy in haemophilia--going for cure?

Traditional treatment for haemophilia consists of bolus infusion of the missing coagulation factor, either prophylactically or on demand, but is complicated by the development of inhibitory antibodies to the infused factor. In those cases, as well as in patients with platelet defects or factor VII (FVII) deficiency, recombinant human activated FVII has been successfully used, but carries the disadvantage of a short plasma half-life. As an alternative, emerging methodology based on gene transfer may be utilized to provide effective haemostasis in patients with coagulation defects. The goal of this article is to introduce the novel concept of continuous expression of activated FVII from a donated gene for the treatment of haemophilia, and to review the safety and efficacy data that have been produced so far by this approach in small and large animal models.