Vical Incorporated announced the issuance of US Patent No. 7,582,613 covering Vaxfectin-formulated DNA vaccines for influenza. The patent provides broad coverage for any circulating or potential influenza viruses, including both seasonal and pandemic strains.

The company is currently developing Vaxfectin-formulated DNA vaccines for both H5N1 avian-origin and H1N1 swine-origin pandemic influenza. Both vaccines are formulated with the company's Vaxfectin adjuvant, a novel lipid-based formulation which has demonstrated significant immune-enhancing ability with a broad range of DNA vaccines and up to 30-fold immune-enhancing ability with a conventional seasonal influenza vaccine. Vaxfectin-formulated H5N1 influenza DNA vaccines completed phase 1 human testing in 2008.

DNA vaccines encode certain proteins associated with a target pathogen, rather than using any part of the pathogen itself, and can prime the immune system as well as induce potent antibody and T-cell immune responses. DNA vaccines contain no viral particles, are non-infectious, and can be administered on a repeat basis without unwanted immune responses. Additionally, DNA vaccines have the potential to achieve proof of concept more quickly and cost-effectively than conventional vaccines, and can be manufactured using uniform methods of fermentation and purification, allowing significantly faster development and production.

The new '613 patent broadly covers DNA vaccines formulated with any cationic lipid/co-lipid adjuvant formulations from the class including Vaxfectin, and targeting any strain of influenza. It adds to Vical's family of patents in the United States and other key regions based on the company's discovery that administering genetic sequences such as DNA or RNA into the body, without the use of viral delivery vehicles, may cause expression of the proteins encoded by the genetic sequences. Vical has additional issued patents covering the composition and use of the Vaxfectin adjuvant.

Vical researches and develops biopharmaceutical products based on its patented DNA delivery technologies for the prevention and treatment of serious or life-threatening diseases.