AAV-mediated gene therapy for hemophilia.

Gene therapy for hemophilia has been contemplated since the coagulation Factor genes responsible for the disease were cloned 20 years ago. Multiple approaches towards the delivery of Factors VIII or IX, the defective genes in the most common forms of hemophilia, have resulted in positive results in animals, and largely equivocal results in human clinical testing. Use of vectors based on adeno-associated virus has led to robust and sustained cures in hemophilic mice and dogs, and intriguing preliminary results in small or ongoing clinical trials. As more clinical experience is gained, solving delivery issues will be of paramount importance and will lead to more clinical success. This success will permit hemophilia to be cured following a single injection of the normal gene.