The Food and Drug Administration plans to loosen the rules for approving new treatments for Alzheimer’s disease.
Drugs in clinical trial would qualify for approval if people at very
early stages of the disease subtly improved their performance on memory
or reasoning tests, even before they developed any obvious impairments.
Companies would not have to show that the drugs improved daily,
real-world functioning.
For more than a decade, the only way to get Alzheimer’s drugs to market
was with studies showing that they improved the ability of patients not
only to think and remember, but also to function day to day at
activities like feeding, dressing or bathing themselves.
The proposal, published online Wednesday in The New England Journal of Medicine,
could help millions of people at risk of developing the disease by
speeding the development and approval of drugs that might slow or
prevent it.
The proposed policy could also be a boon for the pharmaceutical industry
and researchers. They have often felt stymied by regulations that left
them uncertain of how to get drugs tested and approved for marketing to
people early in the course of Alzheimer’s, when the medications are most
likely to be useful.
Several studies are being planned for people at high risk of developing
Alzheimer’s, and the proposed regulations should lead to even more
clinical trials, said Dr. P. Murali Doraiswamy, an Alzheimer’s
researcher and professor of psychiatry at Duke University School of
Medicine.
“There is more motivation now to invest in the field,” Dr. Doraiswamy
said. But, he added, the proposal also comes with risks.
The F.D.A. would require companies to study the drugs after they were on
the market to show they actually benefited patients. But these studies
might not be randomized clinical trials and so would not be as rigorous
as the studies that led to approval. Even with less rigorous studies, it
might be hard to get the evidence, Dr. Doraiswamy said.
“A lot of companies drag their feet and never do a postmarketing study,”
he said. Even if they do one, it may take years to find out whether a
drug works. Meanwhile, millions of people may be taking it, at great
expense.
The agency is trying to resolve a quandary with its new policy: How can
you show a drug works if patients are so early in the course of the
disease that they have no obvious deterioration in their cognitive
abilities or daily functioning?
In draft guidelines to the industry last month, the agency outlined a
way to resolve the problem by changing the criteria for drug approval.
Those at a very early stage of the disease, with no obvious symptoms,
could be studied with cognitive tests. Those with mild symptoms could have a combined test of function and cognition.
With the draft guidelines, the agency is soliciting comments from the
public and industry and may make revisions, said a spokeswoman, Sandy
Walsh. But, she added, “we are ready to move forward with the plan.”
In the paper published on Wednesday, the agency aimed to explain its
perspective to a wider audience. “Our goal was to provide as much
regulatory clarity as possible,” said Dr. Nicholas Kozauer, a clinical
team leader in the agency’s division of neurology products. “We would
encourage companies to start thinking along these lines.”
Companies and researchers were elated, saying the old regulations had hobbled the field.
“This is really a huge advance,” said Dr. Eric Siemers, senior medical
director for the Alzheimer’s disease team at Eli Lilly & Company.
“Kudos to the F.D.A.”
Dr. Sean Bohen, senior vice president at Genentech
for early development, praised the policy, but said he worried about
how to develop appropriate tests to identify subtle cognitive changes.
“There is a lot of uncertainty,” Dr. Bohen said. “But it is an admirable effort. We have to start somewhere.”
Even before the F.D.A. issued its proposal, several companies and the
National Institutes of Health had been planning studies of people who
are very early in the course of the disease.
Dr. Paul S. Aisen of the University of California, San Diego, and Dr.
Reisa Sperling of Harvard are leading a federally financed study that
will enlist 70-year-olds who seem perfectly normal but are accumulating
amyloid plaques in their brains, a sign that Alzheimer’s could arise
within about 15 years. Of 1,000 people with plaques, half will get an
experimental drug made by Lilly and the rest will get a placebo. The
study will also include 500 70-year-olds without plaques, for
comparison.
The researchers will assess the drug by giving subjects several tests,
including ones that involve remembering lists of words and paragraphs
and tests of an ability to follow instructions to change symbols to
letters. Large studies indicate that people who are going to get
Alzheimer’s decline faster on these tests than those who will not get
the disease. If the drug works, it may slow or stop that decline.
Later this year, Lilly will start a new test of a drug in people with
mild symptoms. The drug was already tested in a mixed group of patients,
some with mild symptoms and some with more advanced disease. It failed.
But the company gave its raw data to academic researchers who
discovered that if they looked only at memory tests and only at patients
with mild disease, it seemed to benefit them. So the company will redo
the study with just those who now seem most likely to be helped.
Genentech is planning a study of its own drug in people who have no
symptoms, but have a gene mutation that virtually guarantees they will
get Alzheimer’s eventually. The hope is that the drug will prevent or
delay it. But if there are no symptoms, Dr. Bohen asked, what is the
best way to look for subtle cognitive changes? The agency will not
accept changes on brain scans alone as evidence of efficacy. Yet it
could take years for symptoms to develop in those with the gene.
“It feels like we are taking a risk,” Dr. Bohen said.
The company, he added, will be sending a comment to the F.D.A.
Source:http://www.nytimes.com/
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