NIAID Public-Private Partnerships Seek to Develop HIV/AIDS Vaccine

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ensure continuous progress toward a testable vaccine while at the same time rewarding companies for
research accomplishments made along the way," states Dr. Johnston.
Each of the initial HVDDT contracts proposes using a DNA-based HIV vaccine for the initial
immunization. The proposals differ in the unique properties of the DNA, the specific immune response that
is targeted, the delivery system used, and the manner of boosting the initial vaccine. Each of the proposed
vaccines contains the genetic information to make specific HIV proteins, either from the outer viral envelope
or the internal viral core, to induce an immune response. The vaccines do not contain enough genetic
information to construct a complete virus, and therefore will pose no threat of HIV infection to study
participants. The four research organizations that have received an award and a summary of their proposed
projects are listed below.
Advanced BioScience Laboratories, Inc. (ABL), Kensington, MD
Under the direction of Phillip Markham, Ph.D., researchers from ABL and the University of
Massachusetts Medical School will develop and test a DNA vaccine containing genes for envelope proteins
from HIV strains isolated around the world. Study participants will receive non-DNA booster vaccines
consisting of engineered, or recombinant, HIV proteins. The researchers will explore ways to enhance the
antibody response to this vaccine and hope that this combination will provide broad immunity against the
different subtypes of the virus found worldwide. ABL is an affiliate of Organon Teknika Corporation in
Durham, NC.
Chiron Corporation, Emeryville, CA
Susan Barnett, Ph.D., and colleagues at Chiron will produce a DNA vaccine candidate based on a
common U.S. HIV subtype called clade B. They will also work on a vaccine based on a clade C virus, the
most common HIV subtype in sub-Saharan Africa and India. The vaccines, consisting of HIV envelope and
core protein genes, are designed to stimulate antibodies and T cells that attack the virus and virus-infected
cells, respectively. The DNA vaccine will be followed by a booster vaccine consisting of alphavirus
particles, which serve as novel delivery vehicles to ferry a recombinant HIV protein to certain immune cells.
By slightly changing the genetic code of the vaccine's DNA, Chiron scientists hope to improve the ability of
the body to decode the genetic instructions once the vaccine is administered. The investigators will also
study different ways to enhance the immune response to the DNA vaccine.
University of New South Wales, Australia
David Cooper, M.D., will lead a consortium of Australian universities and research organizations in
producing a DNA vaccine that contains HIV genes as well as specific stretches of DNA that directly
stimulate immune responses. The vaccination boost will contain HIV genes contained in a viral (fowlpox)
delivery system that also contains immunity-enhancing genes. This vaccine is designed to stimulate both

antibody and T-cell responses and to generate active immunity at mucosal surfaces, the first site of viral
assault during most HIV infections.
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