Oral delivery of plasmid DNA encoding the Factor IX gene

摘要

Hemophilia B is an X-linked recessive disorder affecting 1 in 25,000 males. The causative mutation lies in the blood coagulation factor IX (FIX) gene and is clinically characterized by internal bleeding, which in its severest form can be life threatening or crippling. Currently, patients are treated by regular intravenous infusions of FIX, therefore, home therapy is not an option. Often patients are administered with relatively high doses of FIX at a given time and this may contribute to the generation of inhibitory alloantibodies in 2-3 percent of cases (1). Many groups have studied the potential of gene therapy for FIX delivery. Although, it may be difficult to achieve physiological levels of FIX by either in vivo or even ex vivo gene transfer, studies have shown that maintenance of FIX at >1 percent of normal levels can be therapeutic in severely affected individuals (2).