Tau drug shows early promise in Alzheimer's
CHICAGO (Reuters) - An Alzheimer's drug that attacks abnormal tangles in the brain appeared to slow progression of the disease, British researchers said on Tuesday, but doctors cautioned that the results are early.
The drug, made by private biotechnology company TauRX and called Rember, produced a significant improvement in key measures of thinking and memory in people with moderate Alzheimer's disease, company officials said.
The drug is among the first to attack tangles of tau protein in the brain that are strongly associated with dementia in Alzheimer's disease.
"We've demonstrated for the first time we can halt the disease by a treatment that aims to dissolve the tangles," said Claude Wischik of the University of Aberdeen and chairman of TauRX Therapeutics in Singapore.
The researchers tested 321 patients with mild to moderate Alzheimer's disease at 17 centers in the United Kingdom and Singapore, they told the International Conference on Alzheimer's Disease in Chicago.
They evaluated the patients at intervals over seven years. "We've held the disease at bay for a total of 19 months, whereas the control group declined at the expected rate," he said in an interview.
But other doctors said the drug needed more study.
"It's a phase 2 trial," said Dr. Sam Gandy, of Mount Sinai School of Medicine in New York, who serves on an advisory council of the Alzheimer's Association.
"Predicting anything from a phase 2 trial is dangerous. All I can say is it is encouraging enough to move on to a phase 3 trial," Gandy said. Phase 3 trials look at whether a drug works in large groups of people.
"I would very much like to believe it is going to work but we don't know," Marcelle Morrison-Bogorad, director of the division of neurology for the National Institute on Aging, said in an interview.
Many researchers have been working to develop drugs to target amyloid plaques, the sticky clogs that build up in the brains of Alzheimer's patients.
The theory had been that if drugs can remove these plaques, doctors could alter the course of disease. But several drugs that have managed to remove these plaques have failed to show a benefit to patients.
Researchers presented results on a nasal spray on Monday that targets tau. In people with mild cognitive impairment, a precursor to Alzheimer's, it helped improve some measures of memory over three months.
Morrison-Bogorad said she is encouraged that researchers are now studying the tangles of Alzheimer's disease in addition to amyloid.
"I think eventually we will have a combination cocktail of drugs. I don't think it will be one thing," she said.
Alzheimer's disease is incurable and is the most common form of dementia among older people. It affects the regions of the brain involving thought, memory and language.
(Editing by Maggie Fox)
