We are developing a ZFN-mediated gene editing approach to hemophilia A and B in collaboration with Shire AG. This program is currently in preclinical stage studies.
Hemophilia, a rare bleeding disorder in which the blood does not clot normally, is an example of a monogenic disease (a disease that is caused by a genetic defect in a single gene). There are several types of hemophilia, including hemophilia A (caused by a defect in clotting Factor VIII) and hemophila B (caused by a defect in clotting Factor IX). Clotting factors help the blood clot and stop bleeding when blood vessels are injured. Hemophilia usually occurs only in males. About 18,000 people in the United States have hemophilia and each year, about 400 babies are born with the disorder. Approximately 12-15% of those individuals have hemophila B. The standard treatment for individuals with hemophilia B is infusion of Factor IX concentrates or recombinant Factor IX to replace the defective clotting factor. People with severe forms of the disease may need ongoing, preventive infusions.
Sangamo’s Therapeutic Approach
Our ZFN-mediated gene-editing technology enables the specific modification of any DNA sequence in any gene and has the potential to provide a unique solution for the treatment of monogenic diseases. We have demonstrated functional correction of the human factor IX gene by direct delivery of ZFNs in a mouse model of the disease. Further preclinical studies are ongoing to develop a single course of treatment for hemophilia B, which will provide a permanent correction and reduce or eliminate the need for infusions of Factor IX clotting factor products.