Canadian patents No. 2,425,745 and No. 2,049,287 cover such administration with and without cationic lipids, respectively. Covered uses of the technology include vaccines, therapeutics, and research and development applications.

Vical holds issued U.S. and foreign patents concerning this core technology and related enhancements, applications, and manufacturing processes. A number of vaccine and therapeutic applications of the technology are currently under development by Vical and its collaborative partners, including Merck & Co., Inc., Sanofi-Aventis Group, Merial Ltd. (a joint venture between Merck and Sanofi-Aventis), Corautus Genetics Inc., Aqua Health Ltd. (an affiliate of Novartis Animal Health Inc.), and the U.S. National Institutes of Health.

Vijay B. Samant, President and Chief Executive Officer of Vical, said, "We are pleased to establish broad intellectual property coverage in Canada comparable to our core technology coverage in the United States. These Canadian patents extend our existing and expanding patent estate in another key international region and further validate Vical's global leadership position in non-viral gene delivery."

The key discovery leading to the company's patented core technology was that living tissues can take up polynucleotide genetic material directly, without the use of viral components, and subsequently express the proteins encoded by the genetic material for periods ranging from weeks to more than a year. Application of this technology typically involves designing and constructing closed loops of DNA called plasmids, or pDNAs. These pDNAs contain a DNA segment encoding the protein of interest, as well as short segments of DNA that control protein expression. Plasmids can be manufactured using uniform methods of fermentation and processing. This could result in faster development times than technologies that require development of product-specific manufacturing processes.

Since the initial discovery of the core DNA delivery technology, Vical researchers have improved the plasmid design to provide increases in efficiency of gene expression and immunogenicity. In addition, the company is developing other formulation and delivery technologies to enhance DNA expression or increase the immune response in DNA vaccine applications. Vical owns broad rights in the United States and in other key markets to certain non-viral polynucleotide delivery technologies through its patents and licenses.

Vical's gene-based approach may offer safer and more cost-effective alternatives for the prevention or treatment of cancer, infectious diseases and other diseases.

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