Chelation Therapy May Ease Alzheimer's
Metal Chelation Therapy May Slow Progression of Alzheimer's Disease
Dec. 15, 2003 -- A new approach in treating Alzheimer's disease
may help improve mental functioning in those with the most severe forms of the
A preliminary study indicates that metal chelation therapy,
which targets the proteins involved in creating brain plaques that affect
people with Alzheimer's disease, may help slow the progression of the disease.
Although the study only involved a small number of patients, researchers say it
could open up new directions in Alzheimer's disease treatment.
Metal chelation therapy involves using drugs that block metal
ions from interacting with other molecules in the body.
In this study, researchers used the chelation therapy drug
clioquinol and found that it lowered levels of the protein beta-amyloid in
people with moderately severe forms of Alzheimer's disease (AD). Researchers
say that lowering levels of this protein in the blood may block the production
or accumulation of it in the brain and slow Alzheimer's progression.
The results appear in the December issue of Archives of
Chelation Therapy and Alzheimer's Disease
Researchers say that chelation therapy is thought to work by
preventing zinc and copper ions from binding to beta-amyloid, which helps
dissolve the protein and prevent it from accumulating in the brain. A buildup
of "plaque" in the brain, which includes the protein beta-amyloid -- is
thought to cause Alzheimer's disease.
In this phase-two clinical trial, researchers compared the
effects of clioquinol with a placebo in 36 people with moderately severe
Alzheimer's disease for 36 weeks. Half of the patients received escalating
daily doses of the drug twice a day and the others received a placebo.
Tests measured the participant's mental function as well as
beta-amyloid levels throughout the study.
By the end of the study, researchers found that plasma
beta-amyloid levels declined significantly in the most severely affected
patients treated with clioquinol compared with those who received the placebo
who's levels continued to increase.
Alzheimer's patients that had taken clioquinol also had better
scores on test of mental function.
The study showed chelation therapy was well tolerated in people
with Alzheimer's disease. Researchers say those results merit further study of
the treatment in larger groups of patients.
The Next Step in Alzheimer's Treatment
In an editorial that accompanies the study, Roger N. Rosenberg,
MD, editor of the Archives of Neurology, says that chelation therapy may
be a promising new Alzheimer's treatment.
"Clearly, it is an innovative therapeutic approach to AD
and merits a closer and more comprehensive assessment in larger clinical
trials," says Rosenberg.
Experts say if more studies confirm these results, it may solve
an important issue in Alzheimer's disease research.
"If amyloid "plaque-buster" drugs are effective in
preventing or treating Alzheimer's, this may solve the longstanding, often
heated controversy surrounding the issue of whether amyloid really causes
Alzheimer's or is instead an innocent bystander," says William Thies, PhD,
vice president of medical and scientific affairs at the Alzheimer's
Association, in a statement released today. "A positive result would lead
to a redoubled effort at more and better "anti-amyloid" medicines; a
negative result will send the world's Alzheimer experts back to "square