Adenovirus-Associated Virus Vector–Mediated Gene Transfer in Hemophilia B

Background Hemophilia B, an X-linked disorder, is ideally suited for gene therapy. We investigated the use of a new gene therapy in patients with the disorder. Methods We infused a single dose of a serotype-8–pseudotyped, self-complementary adeno virus-associated virus (AAV) vector expressing a codon-optimized human factor IX (FIX) transgene (scAAV2/8-LP1-hFIXco) in a peripheral vein in six patients with severe hemophilia B (FIX activity