But experts who saw the results for the drug Rember were heartened.
"These are the first very positive results I've seen" for helping patients maintain mental performance, said Marcelle Morrison-Bogorad, director of Alzheimer's research at the National Institute on Aging. "It's just fantastic."
The federal agency funded much of the early research that led to drugs like Rember that target the tangles of Alzheimer's, made up of a protein called tau. For decades, scientists have focused on a different protein -- sticky beta-amyloid deposits -- but have yet to get a workable treatment.
The four Alzheimer's drugs currently available just ease symptoms of the mind-robbing disease, which afflicts more than 5 million Americans and is mushrooming as the population ages.
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