T H E N I H C A T A L Y S T | M A Y J U N E 2006 |
|
VRC Celebrates 5thMOVING VACCINOLOGY FROM BASIC SCIENCE TO GLOBAL HUMAN TRIALS |
by Fran Pollner |
VRC
Director Gary Nabel
|
|
The
Dawn of Creation: NIAID Director Anthony Fauci (right) traces the beginnings
of the VRC to December 1996, when he and thenNIH Director Harold
Varmus were invited to the Oval Office to explain HIV science to President
Bill Clinton and Vice President Al Gore. The historical photo shows Fauci
describing the CCR5 receptor to Clinton (right) and Gore (left), with
Varmus (far left) looking on. By the end of the session, Fauci quipped,
"Vice President Gore was wondering whether he had actually
discovered the CCR5 receptor"and Clinton was convinced of the
need to create a center that would encompass all aspects of developing
an AIDS vaccine, from basic research through vaccine production. It was
five months later, in May 1997, that Clinton announced that the VRC was
on the drawing board.
|
By
the tender age of five, the VRC had launched
14 clinical vaccine trials and generated 14 clinical-grade vaccines that entailed
31 vaccine runs, one for each of the individual components of the tested vaccines.
Eight
of the vaccines were anti-HIV candidates, and the other six were targeted against
the likes of the Ebola, West Nile, and SARS viruses, VRC Director Gary
Nabel recounted as he took stock of the VRC's accomplishments and the road
ahead on the occasion of the center's fifth anniversary.
That
disease breakdown reflects the VRC's original and continuing focus on HIV and
AIDS, as well as its early, logical expansion into related emerging challenges.
The
scope of VRC activities also reflects the concept behind its creationto
house in one facility the human and physical resources to develop vaccines from
start to finish, from basic research to vaccine production and clinical trials,
observed NIAID Director Anthony
Fauci, who triggered the memories of the assembled celebrants with a bit
of VRC history.
Harmonic
Convergence: (left to right): VRC Director Gary Nabel; Pontiano Kaleebu,
assistant director of the Uganda Virus Research Institute, Entebbe, and
president of the WHO AIDS vaccine program; Barney Graham, chief, Viral
Pathogenesis Laboratory and Clinical
Trials Core, VRC; and Stanley Plotkin, world-renowned vaccinologist
|
Engineering
Immunity: Two of the guest speakersStephen Harrison (left),
Howard Hughes investigator and Harvard structural biologist, and David
Baltimore, president of the California Institute of Technology in Pasadenadiscussed
strategies to bring neutralizing antibodies to bear against HIV, a quest
VRC Director Gary Nabel called the "Holy Grail" of AIDS vaccine
development
|
Homing
in on AIDS vaccinology, Nabel discussed the details of the VRC's recent advance
into Phase II clinical testing of its multigene, multiclade DNA-prime/adenovirus-boost
AIDS vaccine.
The
six-plasmid construct contains versions of HIV genes gag, pol,
and nef, as well as three modified env genes, one from each of
clades A, B, and C.
Designed
to cover the major subtypes found throughout the world, the vaccine will be
tested at sites in the United States, Brazil, Haiti, Jamaica, Botswana, and
South Africa.*
Each
component underwent testing alone and in combination in the DNA construct, in
the adenovirus vector, and then in the prime-boost sequence. "The DNA-adenovirus
platform proved to be an effective immunogen in humans, which we did not know
before," Nabel said, noting that the prime-boost response is "greater
than the sum of its parts."
Eliciting
broadly neutralizing antibodies remains a challenge, which is being addressed
in ever more sophisticated ways, he said.
Another global priority, Fauci noted, is to develop a vaccine that would obviate the need to reconstruct the flu vaccine each year. Such a universal vaccine for seasonal, or standard, flu would also obviate the need to respond in a crisis manner to potential pandemic flu, he observed.
*The VRC vaccine is also being tested by the International AIDS Vaccine Initiative in Phase I studies in Kenya and Rwanda and by the U.S. Military HIV Research Program in Phase I and II studies in Uganda, Kenya, and Tanzania..