CLINICAL TRIAL SHOWS ISLET TRANSPLANTATION IS A PROMISING PROCEDURE FOR CERTAIN PATIENTS WITH SEVERE TYPE 1 DIABETES

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U.S. Department of Health and Human Services 
NATIONAL INSTITUTES OF HEALTH 
NIH News 
National Institute of Allergy and Infectious Diseases (NIAID)
<http://wwww.niaid.nih.gov/>

EMBARGOED FOR RELEASE: Wednesday, September 27, 2006, 5:00 p.m. ET 

CONTACT: Jason Socrates Bardi, 301-402-1663, <jbardi@xxxxxxxxxxxxx>

CLINICAL TRIAL SHOWS ISLET TRANSPLANTATION IS A PROMISING PROCEDURE FOR
CERTAIN PATIENTS WITH SEVERE TYPE 1 DIABETES

The first international, multicenter trial of the Edmonton Protocol -- a
standardized approach to the transplantation of insulin-producing islets
-- demonstrates that this may be an appropriate therapy that can
dramatically benefit certain patients with severe complications of Type
1 diabetes mellitus. 

As described in the September 28, 2006 issue of "The New England Journal
of Medicine," 36 adult volunteers at nine clinical trial sites in North
America and Europe received up to three infusions of islets, which are
non-functioning in people with Type 1 diabetes. The trial was designed
to gauge how well the transplanted islets would function in regulating
blood sugar levels.

Led by James Shapiro, M.D., Ph.D., of the University of Alberta,
Edmonton, Canada, and involving an international team of islet
transplant researchers, this trial was conducted by the Immune Tolerance
Network (ITN). Headquartered at the University of California, San
Francisco, the ITN is an international consortium of clinical
investigators supported by the National Institute of Allergy and
Infectious Diseases (NIAID), the National Institute of Diabetes and
Digestive and Kidney Diseases (NIDDK) and the Juvenile Diabetes Research
Foundation (JDRF). NIAID and NIDDK are both components of the National
Institutes of Health (NIH).

"The results of the trial show the feasibility and reproducibility of
islet transplantation using the Edmonton Protocol and has promising
implications for the future of treating type 1 diabetes," says NIH
Director Elias A. Zerhouni, M.D.

A year after the final treatment, 44 percent of the transplant
recipients no longer needed insulin injections, and an additional 28
percent had partial islet function, which was associated with resolution
of hypoglycemic unawareness -- a severe complication of diabetes in
which people can no longer recognize early symptoms of low blood sugar.
Insulin independence did not persist indefinitely in most cases, and
less than a third of the people who had been freed from insulin after
one year remained so by two years. However, individuals with functioning
islets had improved control of their diabetes, even though they still
needed to take insulin shots. Further research will be needed to improve
and prolong the beneficial effects of the procedure, the researchers
say.

"Dr. Shapiro and the ITN research team have improved our understanding
of the potential of islet transplantation for certain patients with Type
1 diabetes," says NIAID Director Anthony S. Fauci, M.D. "Ongoing studies
will further define the clinical utility of this approach." 

"This really shows that islet transplantation can be tremendously
successful in protecting against hypoglycemic unawareness," says Dr.
Shapiro. 

About five to ten percent of the estimated 21 million Americans with
diabetes have Type 1 diabetes -- an autoimmune disease in which the body
loses its ability to make insulin due to destruction of islets. Islets
are clusters of cells in the pancreas that produce insulin, a hormone
the body requires to use glucose (sugar) as a source of energy. This is
different from the more common Type 2 diabetes, in which the body
produces insulin but has a reduced ability to use it properly. Without
insulin, very high levels of glucose accumulate in the blood, causing
injury to nerves and blood vessels; at the same time, the glucose is
unable to enter cells where the body can use it. Without insulin shots,
this condition is fatal. Even with insulin shots, people with Type I
diabetes cannot achieve perfectly normal control of their blood sugar.
As a result, most people with Type 1 diabetes eventually develop one or
more complications, such as heart disease and damage to the eyes, nerves
and kidneys. 

Healthy individuals and most people with Type 1 diabetes know when their
blood sugar is low. Over time, however, some people with Type 1 diabetes
develop hypoglycemic unawareness. This condition may make them
vulnerable to sudden and severe confusion, fainting and even death if
untreated. People with this condition may be unable to perform routine
tasks such as driving.

In the last few decades, doctors have been able to treat Type 1 diabetes
with pancreas transplantation. The transplanted pancreas senses blood
sugar and produces insulin. Many people with diabetes who have taken
daily insulin injections for years have achieved total insulin
independence after pancreas transplantation -- often for years after the
transplant. About 1,500 pancreas or pancreas/kidney transplants are
performed every year in the United States, and nearly 20,000 of these
operations have been performed in the last two decades.

Despite this success, pancreas transplants are not routinely done in
patients with Type 1 diabetes because it is a major surgery that carries
associated surgical and anesthetic risks. Even without complications, it
requires several weeks of recovery at home. In addition, a transplant
recipient must stay on immunosuppressive drugs to prevent rejection of
the transplanted pancreas. These drugs can have serious side effects,
such as kidney damage and vulnerability to infection. For these reasons,
pancreas transplantation is almost always reserved for patients who are
already undergoing kidney transplantation.

Since the 1970s, doctors have been experimenting with a less invasive
procedure, islet transplantation. Islets can be isolated from the
pancreas of a deceased donor and then infused into a patient's portal
vein, a large vessel that carries blood into the liver. Once in the
liver, the islets settle in small blood vessels and begin sensing blood
sugar content and producing insulin to control it. This is a safer
procedure than a pancreas transplant and can be done in a few hours.
Islet transplantation is not as effective as pancreas transplantation,
however, in eliminating the need for insulin shots.

In 2000, Dr. Shapiro and his colleagues reported data on seven patients
who achieved insulin independence after islet transplantation following
a standardized procedure that he designed, which became known as the
Edmonton Protocol. The Edmonton Protocol standardizes the procedure for
preparing high-quality islets for infusion, testing the function of
these islets and transplanting them into the recipient. It also makes
use of a regimen of newer immunosuppressants that are less toxic to
islets than some older drugs. However, toxicity remains a problem. Some
patients in the trial stopped taking their immunosuppressants because of
side effects, and as a result, they lost their transplanted islets. 

The 36 participants in the clinical trial (mean age 41) had lived with
diabetes for an average of 27 years. Each received between one and three
infusions of islets. The majority of them had at least partial islet
function one year after their final islet infusion, and almost all who
did had resolution of hypoglycemic unawareness even if they were not
freed from daily insulin injections.

"Even a small number of functioning islets seems sufficient for them to
be able to detect low blood sugar and be cured of hypoglycemic
unawareness," says Nancy D. Bridges, M.D., chief of the Transplant
Immunobiology Branch at NIAID.

The nine clinical sites participating in the trial are: University of
Alberta, Edmonton, Canada; University of Miami; University of Minnesota;
Harvard Medical School; Pacific Northwest Research Institute; Washington
University, St. Louis; Justis-Liebig University, Giessen, Germany;
University of Milan, Italy; and University Hospital of Geneva.

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 www.nih.gov.
  
##

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REFERENCE: J Shapiro et al. International trial of the Edmonton Protocol
for islet transplantation. "New England Journal of Medicine" DOI:
10.1056/NEJMoa061267 (2006).

---------------------------------
 
This NIH News Release is available online at:
http://www.nih.gov/news/pr/sep2006/niaid-27b.htm.

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