SAN DIEGO, Dec. 13, 2010 (GLOBE NEWSWIRE) -- Vical Incorporated (Nasdaq:VICL) announced today that the company's Vaxfectin® adjuvant has significantly boosted the immune response of DNA-based vaccines against a range of pathogens and cancer in preclinical models from rodents to non-human primates. Vaxfectin® has demonstrated similar effects with protein- and peptide-based vaccines in preclinical models. Vaxfectin®-formulated H5N1 influenza DNA vaccines were well-tolerated and elicited durable immune responses within the predicted protective range in initial human studies.

"Vaxfectin® has many of the desired features of a successful adjuvant," said Alain P. Rolland, Pharm.D., Ph.D., Vical's Executive Vice President of Product Development, "including the ability to significantly improve immune responses and favor specific types of immune responses. With a promising safety profile in preclinical and initial clinical studies, ease of formulation, stability and low manufacturing costs, Vaxfectin® is well-positioned as a potential 'universal' adjuvant for either immune enhancement or dose sparing applications in a broad range of infectious disease and cancer vaccines. A comprehensive new review of Vaxfectin® results published in the journal Expert Opinion on Drug Delivery^[1] details Vaxfectin®'s development to date and should help us expand our outreach to potential licensees."

Vaxfectin® has been shown in multiple animal models to significantly increase the antibody and T-cell immune responses to antigens expressed from plasmid DNA vaccines. Results from two Phase 1 clinical trials of Vaxfectin®-formulated H5N1 influenza DNA vaccines demonstrated strong antibody responses and achieved T-cell responses in 75% to 100% of subjects in various dose cohorts. Vaxfectin® has demonstrated similar effect with protein-based vaccines, and the formulation can be adjusted to favor specific immune responses. The current publication reviews non-clinical immunological and efficacy studies of Vaxfectin® in several infectious disease and cancer models, preclinical safety and toxicology studies, clinical development of Vaxfectin®-formulated DNA vaccines, and studies of Vaxfectin®'s mechanism of action.

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, including: whether Vaxfectin® can successfully be used as a universal adjuvant for a broad range of vaccines, if any; whether Vical or others will pursue development of any Vaxfectin®-formulated vaccine candidates; whether Vical will license Vaxfectin® to others as an adjuvant for specific vaccine applications; whether any vaccine candidates will be safe and tolerable, or effective in eliciting immune responses; 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.

[1] Sullivan S et al. Vaxfectin: a versatile adjuvant for plasmid DNA- and protein-based vaccines. Expert Opin. Drug Del. 2010; 7(12):1433-46, doi: 10.1517/17425247.2010.538047.

CONTACT:  Vical Incorporated

          Alan R. Engbring

          (858) 646-1127

          www.vical.com