New Steps Toward Stopping Alzheimer’s
Results Still to Come for a Highly Watched Drug
June 11, 2007 - Scientists reported some progress in their search for new
drugs to treat Alzheimer’s disease Monday, even while researchers studying a
closely watched new drug said they must rework their data to determine if it is
Researchers attending a major scientific meeting in Washington have not
achieved any “magic bullets” against the brain-wasting effects of Alzheimer’s
disease. At the same time, they say they’re optimistic that a series of new
treatments could prove to slow or reverse the disease.
Scientists studying one promising new drug, called Alzhemed, had hoped to
announce major new findings this week. But the study leader announced that
statistical issues would force scientist to reanalyze their results before
determining if the drug works.
Reworking of data is often a red flag for regulators approving new drugs
because it can be a sign the product did not work as hoped under a company’s
original study design. But researcher Paul Aisen, MD, insisted at the annual
meeting of the Alzheimer’s Association that the move was part of the overall
“This process does not indicate that the drug didn’t work,” said Aisen, a
professor of neurology at Georgetown University, who is leading the Alzhemed
study for Neurochem Inc.
The drug works in theory by blocking the formation of amyloid, an
inflammation-causing protein known to be a key cause Alzheimer’s disease.
Aisen suggested that some early data were “in favor of treatment” instead of
placebo pills, but he said he would not speculate further on whether the drug
“At this point, conclusions can’t be drawn,” he said.
If the drug proves worthy, it could be a major step in Alzheimer’s
treatment. Existing drugs on the market mostly slow the disease’s unrelenting
progression or ease some symptoms. Observers eagerly await Alzhemed’s results
because it could actually be a breakthrough in treating the underlying disease
But for now, that breakthrough remains unproven.
Sam Gandy, MD, who leads the Alzheimer’s Association scientific advisory
council, called the delay “science as usual.”
“This is exactly what we should expect: incremental progress,” said Sam
Gandy, “We don’t expect there to be one single compound” that will prove to be
a cure for the disease.
Russian Drug Advances
Researchers are also eyeing another drug, called Dimebon, which is also
showing some promise in early clinical trials.
Researchers have observed that the drug can delay the onset of memory loss
and deteriorating functioning that are the hallmark of Alzheimer’s. Of a total
of 183 Russian patients, Alzheimer's patients who used the drug three
times per day had better memory scores after three months than those who took
Dimebon was sold as an antihistamine in Russia during the 1980s. Regulators
there then found that it has many of the same chemical properties as
already-approved Alzheimer’s drugs like Aricept. It is now slated for a major
clinical study in the U.S. beginning next year.
Rachelle Doody, MD, of Baylor College of Medicine in Houston, who leads the
drug’s American research team, said patients who took the drug also showed no
change in their ability to perform normal activities like cleaning the house or
talking on the phone, “while those on placebo have had a slow but steady
progression” of their disease.