Vical Updates Herpes Simplex Vaccine Development at ASGCT Conference

Vical Updates Herpes Simplex Vaccine Development at ASGCT Conference


PHILADELPHIA, May 16, 2012 (GLOBE NEWSWIRE) -- Vical Incorporated (Nasdaq:VICL) today announced that results from multiple animal studies with the company's Vaxfectin®-formulated plasmid DNA (pDNA) vaccines against herpes simplex virus type 2 (HSV-2) demonstrate proof of concept supporting the company's decision in early 2012 to advance toward clinical testing, which is expected to begin in 2013. Results from completed prophylactic and therapeutic studies in mice and therapeutic studies in guinea pigs included:

    -- Prophylactic pDNA vaccines encoding HSV-2 glycoprotein D (gD) alone or encoding gD and the HSV-2 tegument proteins UL46 and UL47 provided complete protection from primary and recurrent disease.
    -- Both prophylactic vaccines significantly reduced viral replication at the primary genital infection site.
    -- Both prophylactic vaccines significantly reduced detectable HSV-2 infection at the dorsal root ganglia latent site.
    -- The therapeutic pDNA vaccine encoding gD, UL46 and UL47 significantly reduced the frequency of genital lesion outbreaks in animals with pre-established HSV-2 infections.
    -- The therapeutic vaccine significantly reduced the frequency of genital viral shedding.

Sean M. Sullivan, Ph.D., Vical's Executive Director of Pharmaceutical Sciences, is scheduled to present at 3:30 p.m. EDT on Wednesday, May 16, at the 15th Annual Meeting of the American Society of Gene & Cell Therapy, (Philadelphia – May 16-19). Dr. Sullivan's presentation, "Development of Vaxfectin®-formulated HSV-2 Plasmid DNA Vaccines for Prophylactic and Therapeutic Applications," summarizes the previously reported animal study data supporting the advance to human testing.

HSV-2 is a sexually transmitted virus which is the leading cause of genital herpes. Approximately one out of every six individuals in the United States and an estimated one out of every four worldwide is infected by HSV-2 before age 50. HSV-2 infections are persistent and can result in debilitating genital lesions, as well as periodic virus shedding placing sexual partners at risk. HSV-2 infection also significantly increases the risk of acquiring HIV-1. There is no approved vaccine for HSV-2.

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

The Vical Incorporated logo is available at

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 potential uses and benefits of Vical's vaccine technologies and their potential application in vaccines against HSV-2, 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 or others will advance the HSV-2 vaccine candidate into human clinical testing in 2013, if at all; whether preclinical results will be predictive of results in human clinical testing; whether the HSV-2 vaccine or 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: Alan R. Engbring
         (858) 646-1127