Data Published in Human Gene Therapy Clinical Development Support Safety of AGTC's AAV Vector Manufacturing Process

GAINESVILLE, Fla., Nov. 3, 2014 (GLOBE NEWSWIRE) -- Applied Genetic Technologies Corporation (Nasdaq:AGTC), a clinical stage biotechnology company developing adeno-associated virus (AAV)-based gene therapies for the treatment of rare eye diseases, today announced the publication of data that further validate the safety of the company's proprietary method for manufacturing adeno-associated viral (AAV) vectors. The publication, "Herpes Simplex Virus Clearance During Purification of a Recombinant Adeno-Associated Virus Serotype 1 Vector" appears in the October 2014 issue of Human Gene Therapy Clinical Development.

Since AAV can only replicate in the presence of a helper virus, such as herpes simplex virus (HSV) an early challenge to manufacturing AAV vectors was developing effective methods for removing any helper virus that could replicate or cause infection from the final AAV product. The data published today confirm and quantify the inactivation and removal of the recombinant HSV helper virus used in AGTC's proprietary AAV manufacturing process. This process uses three methods that inactivate and remove the helper virus during purification of the final material. The crude product is first treated with detergent, which breaks open and inactivates the helper virus, and is then purified using two different types of column chromatography, both of which are able to physically remove any remaining helper virus particles. Combined, these three steps yield an AAV vector product that is highly purified with an excellent safety profile.

"AGTC has established a robust, scalable, and proprietary manufacturing process that overcomes many of the previous challenges associated with developing AAV vectors for therapeutic use," said Jeffrey Chulay, M.D., DTM&H, Vice President and Chief Medical Officer, AGTC and senior author on the publication. "These data demonstrate that our process effectively inactivates HSV helper virus and is highly efficient at removing HSV particles from our AAV production runs."

"These results indicate that AGTC's AAV preparations are highly purified and suggest that patients receiving AAV vectors manufactured using the company's proprietary process have a very low risk of HSV-related adverse events," said Terence R. Flotte, M.D., Dean of the School of Medicine, Provost and Executive Deputy Chancellor, Professor of Medical Education, the University of Massachusetts Medical School and the principal investigator on a clinical trial that utilized AAV vectors produced through the AGTC process. "AAV vectors have significant potential in treating a variety of diseases, and a scalable manufacturing process that yields highly pure material is essential for evaluating these vectors in clinical trials and driving therapeutic discovery."

In the newly published quantification study, a known amount of HSV was added to unprocessed AAV material and HSV titers were then assessed at various points throughout the purification process. The initial detergent step resulted in rapid and complete inactivation of the highest amount of HSV that could be tested. Physical removal of HSV particles during the two separate column chromatography steps was measured by adding additional HSV to the material during subsequent purification steps. According to the published data, a clinical dose of AAV vector produced using the AGTC process would contain less than one one-hundredth of a single infectious HSV particle.

"These data demonstrate that AGTC's scalable and cost-effective manufacturing process yields highly pure AAV material, and add to a growing body of data that support the safety and clinical utility of our pipeline programs," said Sue Washer, President and CEO of AGTC. "We believe that our AAV product candidates may transform the care and outcomes for patients with rare genetic retinal disorders and have developed our proprietary manufacturing method in order to realize that potential. We look forward to initiating U.S. clinical trials of our product candidates for achromatopsia (ACHM) and X-linked retinoschisis (XLRS), which is expected in the first half of 2015."

About AGTC

AGTC is a clinical-stage biotechnology company that uses its proprietary gene therapy platform to develop products designed to transform the lives of patients with severe diseases in ophthalmology. AGTC's lead product candidates focus on X-linked retinoschisis, achromatopsia and X-linked retinitis pigmentosa, which are inherited orphan diseases of the eye, caused by mutations in single genes, that significantly affect visual function and currently lack effective medical treatments. AGTC has recently begun development of a product to treat Wet AMD using the company's experience in ophthalmology to expand into disease indications with larger markets.

CONTACT: David Carey Lazar Partners Ltd. T: (212) 867-1768 Corporate Contact: Larry Bullock Chief Financial Officer Applied Genetic Technologies Corporation T: (386) 462-2204

Source:Applied Genetic Technologies