An experimental drug has proved effective in clearing the buildup of protein in the brains of people with mild Alzheimer's disease and slowed their mental decline, results of a preliminary trial have shown.
The outcome raised hopes of a treatment for the disease but experts have cautioned against not reading too much in the findings.
They said the drug, aducanumab was the only the latest antibody to show promise in an early, Phase I drug trial. Other drugs had produced disappointing results in the decisive Phase III efficacy test.
"Although potentially this is an exciting story, it is important to temper any excitement with considerable caution," said Robert Howard, a professor of old age psychiatry at University College London, AFP reported.
"It would be premature to conclude that this is likely to represent an effective treatment for Alzheimer's disease."
The study conducted in the US and Switzerland, involved 165 people with early-stage Alzheimer's disease who were treated with aducanumab for a period of one year.
Some received a monthly injection of the antibody, while others were given a placebo or dummy drug.
The researchers reported an "almost complete clearance" of so-called amyloid plaques in the brains of those who received the treatment.
Meanwhile, in another study researchers found that people over age 65 who frequently took over-the-counter sleep aids and certain other commonly used drugs might be increasing their risk of dementia.
The study considered drugs that had "anticholinergic effects," meaning they blocked a neurotransmittercalled acetylcholine. The class included many drugs, including tricyclic antidepressants such as doxepin, antihistamines and drugs like Detrol (oxybutinin) used to treat overactive bladder.
"We have known for some time that even single doses of these medications can cause impairment in cognition, slower reaction time, [and] reduced attention and ability to concentrate," said Shelly Gray, the study's first author and a pharmacy professor at the University of Washington in Seattle,www.livescience.com reported.
Originally, "the thinking was that these cognitive effects were reversible when you stopped taking the medication."