Vical Announces Issuance of U.S. Patent for Universal Influenza Vaccine Approach

SAN DIEGO, June 3, 2009 (GLOBE NEWSWIRE) -- Vical Incorporated (Nasdaq:VICL) announced today the issuance of U.S. Patent No. 7,537,768 covering the use of influenza virus gene sequences in a universal vaccine that could provide protection against circulating seasonal strains as well as emerging pandemic strains of influenza viruses.

Vical has patented a new influenza vaccine approach based on portions of the virus which are much more consistent between strains than the constantly changing conventional vaccine target, hemagglutinin (HA), and which are highly conserved even between seasonal and potentially pandemic emerging strains. Vical's DNA vaccine technology can induce both antibody and T-cell immune responses against the target portions of the virus, potentially providing a level of protection not available with conventional influenza vaccines. In addition, a vaccine based on this approach may have the potential to provide protection against future pandemic threats from new strains of influenza viruses.

The new '768 patent covers the composition and use of gene sequences encoding highly-conserved influenza proteins-nucleoprotein (NP) and ion channel protein (M2)-which were optimized for use in human vaccination. These gene sequences were derived from common portions of proteins from influenza strains in circulation over a ten-year period. The sequences were then codon-optimized for human expression to provide the greatest level of influenza protein output per vaccine dose. The resulting NP and M2 DNA components could be used in a universal influenza vaccine with the potential to protect against a broad range of circulating or emerging influenza strains. This patent adds to Vical's family of patents in the United States and in 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.

About Vical

Vical researches and develops biopharmaceutical products based on its patented DNA delivery technologies for the prevention and treatment of serious or life-threatening diseases. Potential applications of the company's DNA delivery technology include DNA vaccines for infectious diseases or cancer, in which the expressed protein is an immunogen; cancer immunotherapeutics, in which the expressed protein is an immune system stimulant; and cardiovascular therapies, in which the expressed protein is an angiogenic growth factor. The company is developing certain infectious disease vaccines and cancer therapeutics internally. In addition, the company collaborates with major pharmaceutical companies and biotechnology companies that give it access to complementary technologies or greater resources. These strategic partnerships provide the company with mutually beneficial opportunities to expand its product pipeline and address significant unmet medical needs. Additional information on Vical is available at www.vical.com.

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This press release contains forward-looking statements subject to risks and uncertainties that could cause actual results to differ materially from those projected. Forward-looking statements include statements about the scope of coverage of and potential applications for Vical's patents, the potential uses and benefits of Vical's vaccine technologies and their potential application in vaccines against seasonal or pandemic strains of influenza, as well as Vical's focus, collaborative partners, and product candidates. Risks and uncertainties include whether Vical's technology will be successfully applied; whether Vical's issued patents will be challenged and whether such challenges will have an adverse effect on the scope of the patents; whether Vical will pursue enforcement of its issued patents or be successful in any such enforcement efforts; whether Vical will successfully prosecute additional patent applications and if so, whether such applications will lead to the issuance of additional patents; whether Vical or others will develop any influenza DNA vaccine candidates; whether any strains of influenza will cause a pandemic; whether the company's DNA vaccine candidates will be effective in protecting humans against any strains of influenza; whether any product candidates will be shown to be safe and effective in clinical trials, the timing, nature and cost of clinical trials, whether Vical or its collaborative partners will seek or gain approval to market any product candidates, whether Vical or its collaborative partners will succeed in marketing any product candidates, and additional risks set forth in the company's filings with the Securities and Exchange Commission. These forward-looking statements represent the company's judgment as of the date of this release. The company disclaims, however, any intent or obligation to update these forward-looking statements.

CONTACT:  Vical Incorporated
          Alan R. Engbring
          (858) 646-1127
          www.vical.com