(NEW YORK) -- Dimebon worked well as an antihistamine but not so much as a treatment for Alzheimer's disease.
There was hope that the drug could be used to help thwart the onset of mild to moderate Alzheimer's disease based on successful phase III clinical testing in 2008.
However, Pfizer and Medivation, which were co-developing Dimebon, admitted Tuesday that subsequent late-stage testing showed that the drug had little effect in stemming the most common form of dementia that has been on the increase as the population ages.
Researchers said they had gone further along with the drug than in previous treatments for Alzheimer's, making the decision to pull the plug that much more frustrating.
While not approved for use in the U.S., Dimebon was used for years in Russia as an antihistamine to treat nasal congestion.
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