|NIAID DNA Vaccine for H5N1 Avian Influenza Enters
The first human trial of a DNA vaccine designed to prevent H5N1
avian influenza infection began on December 21, 2006, when the
vaccine was administered to the first volunteer at the National
Institutes of Health (NIH) Clinical Center in Bethesda, MD. Scientists
from the Vaccine Research Center (VRC) at the National Institute
of Allergy and Infectious Diseases (NIAID), one of the NIH Institutes,
designed the vaccine. The vaccine does not contain any infectious
material from the influenza virus.
Unlike conventional flu vaccines, which are developed by growing
the influenza virus in hens' eggs and then administered as a weakened
or killed form of the virus, DNA-based vaccines contain only portions
of the influenza virus' genetic material. Once inside the body,
the DNA instructs human cells to make proteins that act as a vaccine
against the virus.
VRC Director Gary Nabel, M.D., Ph.D., together with a team of
scientists from the VRC recognized the potential for employing
new vaccine technology against influenza, a disease for which effective
vaccines have long been made, but for which the reliability of
supply and manufacturing capacity has been problematic. Dr. Nabel
and his colleagues previously have shown the DNA vaccine approach
to be effective against influenza viruses in animal models, including
highly pathogenic viruses such as the H5N1 strain and the H1N1
virus that caused the deadly 1918 pandemic. The DNA vaccine used
in this study is similar to other investigational vaccines evaluated
by the VRC that hold promise for controlling other viruses, such
as HIV, Ebola, SARS and West Nile.
"An effective H5N1 influenza vaccine would provide a potentially
life-saving advance against a global health threat," notes NIAID
Director Anthony S. Fauci, M.D."More broadly, development of this
DNA vaccine technology has the potential to improve our production
capacity for vaccines to prevent seasonal influenza and other diseases."
"This influenza vaccine trial is further evidence of the ability
of the NIAID Vaccine Research Center to rapidly translate basic
research into potential products," he adds."Our accelerated effort
to understand and find new solutions to pandemic influenza is part
of the NIAID commitment to respond to new emerging infectious disease
threats and to improve public health preparedness."
Highly pathogenic avian influenza A viruses, specifically H5N1,
have emerged in the past decade, causing widespread sickness and
death in domestic and wild bird populations. As of December 27,
2006, 261 laboratory-confirmed human cases of H5N1 had been reported
to the World Health Organization, resulting in death of more than
half of infected individuals. While human cases remain relatively
rare and are largely the result of direct virus transmission from
infected birds, a few cases of human-to-human transmission have
been reported. The severity of disease and the potential for human-to-human
spread has provided a major incentive to accelerate developing
a human vaccine for avian influenza.
With the spread of avian influenza virus, new strains have emerged,
including clade II viruses in Indonesia and elsewhere that have
drifted genetically from the initial strains detected in Southeast
Asia. With this study, the investigators hope to learn whether
new technologies, such as DNA vaccines, can provide protection
against such viruses.
"This vaccine is aimed at newer strains of the H5N1 virus that
currently pose a threat in Indonesia and represents an example
of our ability to respond to shifting viruses with modern technology," says
The study will enroll 45 volunteers between the ages of 18 and
60. Fifteen will receive placebo injections and 30 will receive
three injections of the investigational vaccine over 2 months and
will be followed for 1 year. Volunteers will not be exposed to
The vaccine contains no infectious material, and the virus was
not present during any stage of the manufacturing process, notes
Julie E. Martin, D.O., principal investigator of the study. "It
is impossible for the vaccine to cause infection," she adds, "because
it employs new technology known to safely stimulate broad immune
responses." NIAID researchers will measure immune responses to
the vaccine, assess its safety, and compare its potency to more
traditional vaccine approaches.
Individuals interested in enrolling in the trial may visit http://www.clinicaltrials.gov or
call the VRC toll-free at 1-866-833-LIFE (5433).
The candidate vaccine, synthesized using a modified version of
the hemagglutinin (H) gene from the H5N1 influenza virus, was manufactured
at the VRC Vaccine Pilot Plant. This is the first VRC candidate
vaccine manufactured at the VRC Vaccine Pilot Plant. The candidate
vaccine went from the research bench into clinical trials in less
than 6 months.
For more information on influenza see http://www3.niaid.nih.gov/news/focuson/flu.
Also visit http://www.PandemicFlu.gov for
one-stop access to U.S. Government information on avian and pandemic
News releases, fact sheets and other NIAID-related materials are
available on the NIAID Web site at http://www.niaid.nih.gov.
NIAID is a component of the National Institutes of Health. NIAID
supports basic and applied research to prevent, diagnose and treat
infectious diseases such as HIV/AIDS and other sexually transmitted
infections, influenza, tuberculosis, malaria and illness from potential
agents of bioterrorism. NIAID also supports research on basic immunology,
transplantation and immune-related disorders, including autoimmune
diseases, asthma and allergies.
The National Institutes of Health(NIH) — The Nation's
Medical Research Agency — includes 27 Institutes and
Centers and is a component of the U. S. Department of Health
and Human Services. It is the primary federal agency for conducting
and supporting basic, clinical and translational medical research,
and it investigates the causes, treatments and cures for both
common and rare diseases. For more information about NIH and
its programs, visit http://www.nih.gov.