UPDATE 2-Allon drug boosts memory in pre-Alzheimer patients

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CHICAGO, July 28 (Reuters) - A nasal spray made by Allon Therapeutics Inc (NPC.TO) significantly improved some measures of memory in patients with mild cognitive impairment, a precursor to Alzheimer's disease, researchers reported on Monday.

The drug, AL-108, is among the first of a new class of Alzheimer's treatments to target the fibrous tangles in the brain caused by an abnormal build-up of the protein tau.

Most drugs under development for Alzheimer's disease have focused on sticky plaques known as beta-amyloid that form clogs in the brain. A number of companies like Allon are now pursuing the fibrous tangles that characterize the disease.

"This makes AL-108 the first drug to validate in humans the importance of the 'tangle' or 'tau' pathway in Alzheimer's," Dr. Donald Schmechel of Duke University Medical Center in Durham, North Carolina, who led the study, said in a statement.

Schmechel and colleagues studied two doses of the drug in 144 patients aged 55-85 at 16 U.S. centers. All had amnestic mild cognitive impairment, a type that is more likely to lead to Alzheimer's disease than other forms of MCI.

MCI is marked by memory, language or other mental declines that are severe enough to be noticed by a family member, but not severe enough to be considered dementia.

The researchers chose this condition to study the drug because they thought people would be better able to report any side effects, Schmechel told the International Conference on Alzheimer's Disease in Chicago.

After 12 weeks, no serious side effects were seen, he said.