Newswise - Researchers from The Wistar Institute recently
reported that a human adenovirus called AdHu26, once thought
uncommon, is not so rare after all. This could be bad news for
scientists eager to use engineered AdHu26 human adenoviruses as
vaccines against HIV and other diseases. In this approach,
adenoviruses, which commonly cause respiratory-tract infections,
are rendered relatively harmless before being used as vectors to
deliver genes from pathogens, which then stimulate the body to
generate an immune response. Yet studies show that a viral vector
may be less effective if the vector is based on a type common in a
population, because humans will have previously developed immunity
to it.
"AdHu26 is considered by some to be rare in nature and thus
there should be less pre-existing immunity. Dr. Hildegund Ertl [at
Wistar] is claiming this is incorrect at least for certain human
populations," says Mark J. Newman, Ph.D., Vice President of
Research and Development at GeoVax Labs, headquartered in Smyrna,
Georgia. In its quest for an HIV vaccine, GeoVax has turned for
help to a poxvirus vector called Modified Vaccinia Ankara (MVA),
originally developed as a safer smallpox vaccine.
"Since we no longer administer smallpox vaccine except to the
military and a select group of first responders for the potential
use of smallpox by bioterrorists and smallpox has been eliminated
from the human population, the vast majority of people are not
being exposed to vaccinia viruses, of which MVA is one," continues
Dr. Newman. "Thus there is a lack of pre-existing immunity, at
least in people who were born after 1971 when the universal use of
the smallpox vaccine was discontinued."
Because of the difficulty raising antibodies that are capable of
totally blocking natural HIV infections, the GeoVax vaccine
approach has focused on raising cellular immune responses in
addition to antibodies, which together should be better able to
block and control the infections than either can alone. The
company's vaccine proteins, which are inactivated proteins from
HIV, are expressed in cells of the vaccinated person following
administration of genetically engineered DNA vectored vaccines and
live viral vector MVA vaccines. MVA was chosen, in part, because of
its safety features but also because a sufficient amount of HIV
genetic material can be inserted which supports the production of
virus-like particles in cells.
These particles mimic immature HIV viruses and present the viral
proteins to the immune system in the correct conformation inducing
both cellular immune responses and antibodies. Testing using
preclinical nonhuman primate models documented the utility of these
vectors for inducing the desired types of immune responses. The
company believes this novel approach may well succeed where the use
of approaches that induce other types of immune responses may
fail.
For more information, log on to www.geovax.com
About GeoVax Labs, Inc.
GeoVax is a biotechnology company developing human vaccines for
diseases caused by HIV
(Human Immunodeficiency Virus - that leads to AIDS) and other
infectious agents. Our goals
include developing HIV/AIDS vaccines for global markets,
manufacturing and testing these
vaccines under GMP/GLP conditions (FDA guidelines), conducting
clinical trials for vaccine
safety and effectiveness, and obtaining regulatory approvals to
move the product forward. All
preventative Phase 1 human clinical trials conducted to date tested
various combinations and
doses of our DNA and MVA vaccines, their ability to raise anti-HIV
immune responses, as well
as the vaccines' safety. Successful results from all Phase 1
testing supported the initiation of the
first Phase 2 testing. GeoVax's Phase 2 human trial began in
January 2009 and will ultimately
involve 300 participants at sites in the United States and South
America. Recently the FDA
granted permission to proceed with a Phase 1 therapeutic trial for
individuals infected with HIV.
Long term, we expect that GeoVax will grant manufacturing and
distribution rights in several
global markets in return for upfront fees, collaborative
development agreements, and royalties on
sales and distribution revenues. Internal vaccine manufacturing and
distribution will also be
considered by GeoVax. For more information, please visit www.geovax.com.
Forward-Looking Statements
Certain statements contained in this release, including
those relating to postponement of the offering, as
well as statements containing words like "plans," "expects," and
other similar expressions in this press
release or the Company's other public communications, are
forward-looking statements that involve a
number of risks and uncertainties. All such forward-looking
statements are subject to certain risks and
uncertainties that could cause actual results to differ materially
from those in the forward-looking
statements. These risks and uncertainties include, but are not
limited to: the possible adverse impact on
the market price of the Company's shares of common stock due to the
dilutive effect of the common stock
and warrants which may be sold in the offering, and the possible
adverse effect of continuing unfavorable
market conditions, as well as other risks and uncertainties, such
as those detailed from time to time in the
Company's Securities and Exchange Commission filings, including
"Risk Factors" in the Company's
most recent Form 10-K.
Contact:
At The Investor Relations Group:
Investor Relations
James Carbonara / Jason Strominger
or
Public Relations
Janet Vasquez / Robin O'Malley
(212) 825-3210
Be sure to see our
GeoVax video on YouTube at: http://www.youtube.com/watch?v=jFuk4RhZfZQ
 
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