Research at Argonne helps Abbott Labs develop anti-HIV drug
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ARGONNE, Ill.
(Sept. 1, 2006) — Back
in 1996, when the Advanced Photon Source at
the U.S. Department of Energy's Argonne National Laboratory first turned
on its brilliant beam of X-rays, scientists from around the world were
excited by the possibilities. Now, 10 years later, one of those “possibilities” is
saving thousands of lives.
One of the early research projects undertaken at the Advanced Photon Source,
which provides the Western Hemisphere's most brilliant X-ray beams, was an
examination of the Acquired
Immune Deficiency Syndrome (AIDS) Human
Immunodeficiency Virus, or HIV.
Designing an effective anti-HIV drug requires very precise design:
the drug must be highly target-specific so that it impacts only the point
where the drug can be most effective. Also important are the lock-and-key requirements
for drug designers. The design must fit the particular structure of the target
molecule, while being flexible enough to accommodate changes in that structure.
Using X-ray crystallography, researchers found the points of attack of the
HIV protease inhibitors – agents that block the breakdown of proteins. Protease
inhibitors stop HIV from making new copies of itself by blocking the last step
in the process, when the virus attempts to replicate.
Out of that discovery came the drug Kaletra®, now the most-prescribed
drug in its class for AIDS therapy and a product of Abbott
Laboratories, which
was one of the earliest users of the Advanced Photon Source.
Abbott Labs is
part of the Industrial
Macromolecular Crystallography Association (IMCA),
which operates one of the beamlines at the Advanced Photon Source through a
contract with the Center
for Advanced Radiation Sources at The University
of Chicago. Researchers took a close-up view of the protein called the HIV
protease, revealing the atomic details of how compounds interact with the protein.
“Kaletra is a clear example of the positive impact derived from research at
our DOE-sponsored facility,” said Murray Gibson, Argonne
associate laboratory director for scientific user facilities. “This premier
national research facility provides the brightest X-ray beams in the Western
Hemisphere to more than 5,000 scientists from around the United States and
the world. These scientists come to the APS from universities, industry, medical
schools, and other research institutions, bringing with them ideas for new
discoveries in nearly every scientific discipline, from materials science to
biology, chemistry, environmental and planetary science, and fundamental physics.
They bring their ideas to the APS because our X-ray beams let them collect
data in unprecedented detail and in amazingly short time frames. The knowledge
they gain promises to have real and positive impact on our technologies, our
health, our economy, and our fundamental understanding of the materials that
make up our world.”
“The development of Kaletra is an excellent example of the critical path of
drug discovery used by pharmaceutical companies,” said Jonathan Greer, vice
president of research for Abbott Labs. “The first leg of the critical path
is discovery, as we identify the target and generate leads toward appropriate
drug properties; second is development, as the target is validated and the
leads optimized, demonstrating the safety and efficacy of the drug candidate.
The new technologies that help with this process, in addition to molecular
crystallography and the X-ray techniques available at the APS, are high-throughput
screening and chemistry, protein biochemistry, automation and the range of
genomics and proteomics processes.”
One of the challenges facing structural biologists and indeed much of biology
has been the slow pace, often measured in months or years, of determining the
structures of biomolecules that are important for advances in energy, health
and the environment. The use of the Department of Energy-funded user facility
allows researchers to speed the process of structure determination, narrowing
the gap between the current pace of discovery and the ability of scientists
to have access to new information.
Because the research done at the Advanced
Photon Source by Abbott Labs researchers was proprietary, the company reimbursed
costs of using the facility for its research. In addition, as a part of the
IMCA organization Abbott helped fund construction of the IMCA beamlines at
the APS, which are openly available to non-IMCA researchers through the APS
general user program. This collaboration between government and industry jointly
advances scientific research.
Abbott researchers began clinical trials with Kaletra in the late 1990s and
the longest clinical study of any HIV treatment – seven years – ended in late
2005 with data demonstrating that patients taking Kaletra in combination with
other antiretroviral agents maintained an undetectable viral load (amount of
virus in the blood) of less than 50 copies per milliliter, as measured by HIV
RNA.
This finding, presented at the European AIDS Conference (EACS), demonstrated
that most patients taking a Kaletra-based regimen as initial therapy for
HIV infection showed sustained antiviral response. It is commonly remarked
that Kaletra is a drug that helped turn a situation where patients were dying
from AIDS to a situation where patients are living with AIDS.
"This impressive seven-year Kaletra data, which demonstrates
sustainable treatment without resistance for most patients new to therapy, is
a hallmark of the importance of research and development in the area of HIV," said
Robert Murphy, M.D., practicing physician and professor, and director of clinical
research in biodefense and infectious diseases, Division of Infectious Diseases,
Northwestern University, Feinberg School of Medicine, Chicago.
Abbott
has been a leader in HIV research since the early years of the epidemic.
In 1985, the company developed the first licensed test to detect HIV antibodies
in the blood and remains a leader in HIV diagnostics. Abbott retroviral and
hepatitis tests are used to screen more than half of the world's donated blood
supply.
Abbott
is a global, broad-based health care company devoted to the discovery, development,
manufacture and marketing of pharmaceuticals and medical products, including
nutritionals, devices and diagnostics. The company employs 60,000 people
and markets its products in more than 130 countries. — Catherine Foster
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