Date: 10/20/2006 6:30:00 AM

Vical Incorporated
(Nasdaq: VICL) today announced that a single injection of the company's lead
avian influenza (flu) DNA vaccine candidate provided 100% protection in
ferrets against lethal challenge with a highly virulent H5N1 virus
(Vietnam/1203/2004).  Conventional vaccines under development for avian flu
typically have required two or more doses in humans, even with novel
adjuvants, to produce the immunogenicity levels expected to provide
protection.

The company had previously demonstrated that two doses of the vaccine
candidate provided 100% protection in mice and ferrets against lethal
challenges with H5N1 virus.  A single-dose vaccine regimen could prove
beneficial during a pandemic, both in extending vaccine supply to protect a
greater number of people, and in achieving protective immune responses as
quickly as possible.  The studies were part of the company's program to
develop a DNA vaccine to protect humans against emerging strains of flu virus
that have the potential to cause a pandemic.  Vical's three-component DNA
vaccine candidate encodes two highly-conserved influenza virus proteins --
nucleoprotein (NP) and ion channel protein (M2) -- plus the H5 avian influenza
virus surface protein, and is formulated with the company's patented
Vaxfectin(TM) adjuvant.

"We are excited by the recent advances in our pandemic flu vaccine
development program," said Vijay B. Samant, President and Chief Executive
Officer of Vical.  "Earlier this week, we presented data from mouse studies
demonstrating the dose-sparing ability of our Vaxfectin(TM) adjuvant when used
with conventional flu vaccines.  Today we presented data from ferret studies
demonstrating the ability to provide complete protection with a single dose of
our Vaxfectin(TM)-formulated avian flu DNA vaccine.  Our goal is to advance
into human testing with this program as quickly as possible, both to provide a
potential defense against a pandemic outbreak and to explore the potential for
a seasonal flu vaccine using a similar approach."

Larry R. Smith, Ph.D., the company's Vice President of Vaccine Research,
presented the data Friday at the annual meeting of the Second International
Conference on Influenza Vaccines for the World (Vienna, October 18 - 20).
Financial support was provided under previously-announced grants from the
National Institute of Allergy and Infectious Diseases (NIAID), National
Institutes of Health (NIH).  All lethal challenge testing was conducted in
BSL-3 facilities at St. Jude Children's Research Hospital under the direction
of Richard J. Webby, Ph.D.

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.

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 results in mouse and ferret studies will
be predictive of results in human studies; whether Vical or others will
continue development of the pandemic influenza DNA vaccine candidate; whether
H5N1 or other strains of avian flu will emerge as pandemic threats; whether
the company's DNA vaccine candidate will be effective in protecting humans
against H5N1 or other strains of avian flu; whether development of an avian
flu vaccine would lead to development of a seasonal flu vaccine; whether the
flu vaccine or any other product candidates will be shown to be safe and
effective; the timing, nature and cost of clinical trials; whether Vical or
its collaborative partners will seek or gain approval to market the flu
vaccine or any other product candidates; whether Vical or its collaborative
partners will succeed in marketing the flu vaccine or any other 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.


    Contacts:  Investors:                    Media:
               Alan R. Engbring              Susan Neath
               Vical Incorporated            Porter Novelli Life Sciences
               (858) 646-1127                (619) 849-6007
               Website:  www.vical.com


SOURCE  Vical Incorporated

Investors, Alan R. Engbring of Vical Incorporated, +1-858-646-1127; or Media, Susan
Neath of Porter Novelli Life Sciences, +1-619-849-6007, for Vical Incorporated

http://www.vical.com/