 Hemophilia A is a condition in which blood is unable to clot effectively. It is caused by a mutation or deletion in the gene that is responsible for producing blood-clotting factor VIII protein. Individuals with hemophilia A suffer from repeated bleeding episodes, often into the joints, which can cause chronic joint disease and sometime results in death due to the inability of the blood to clot efficiently. This chronic joint disease can have significant physical, psychosocial, and quality-of-life effects, including financial burden. The current treatment is intravenous i.v. injections of factor VIII protein products, either 2-3 times weekly or in response to bleeding. 