After the failure of two
novel drugs using antibodies to fight the build-up of brain plaque in
Alzheimer's patients, scientists said they have learned lessons for
The biologic drugs
solanezumab, by pharmaceutical giant Eli Lilly, and bapineuzumab, by Johnson
and Johnson, made it to phase III trials and were taken by thousands of
patients, according to a full report on the research published in the New
England Journal of Medicine.
However, neither succeeded
in improving the cognitive function of patients in the study when compared to a
News of the drugs' failure
first broke in 2012, stunning the research community and dashing the hopes of
millions worldwide whose relatives suffer from the incurable form of dementia.
disappointment from this trial was that if we had shown benefit with a drug
like bapi, it would give people hope that Alzheimer's is a treatable disease,
that we can slow it down," said lead researcher Stephen Salloway,
professor of neurology and psychiatry at Brown University's Warren Alpert
Amyloid plaque build-up
Looking back at the data,
researchers learned that as many as 25% of the people they were studying likely
did not have Alzheimer's disease but some other form of dementia, since they
did not have a significant amount of amyloid plaque build-up in their brains.
Future trials should enrol
only patients who are confirmed to have Alzheimer's with a PET scan and spinal
fluid testing, Salloway said.
Getting the medication to
patients earlier in the progression of their disease could also produce more
tangible effects, he said.
Another approach could be
to pair antibody drugs with drugs such as a beta secretase inhibitor that
maximize amyloid lowering, he said, though the safety of such combinations is
unknown and would require thorough testing.
"Alzheimer's is a
difficult and complex disease, and we are moving forward," said Salloway.
An accompanying editorial
by doctors at University College London and Alzheimer's Research UK said the
two trials "provided valuable information".
Even though the trials and
their failures raised questions about the role played by amyloid beta proteins
that form harmful plaques in the brains of Alzheimer's patients, more research
should continue in this area, the editorial urged.
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