An experimental drug being developed by Roche Holding AG removed amyloid plaques from the brains of Alzheimer’s disease patients in a small early-stage study, according to data published in the Archives of Neurology, the Swiss drugmaker said on Monday.

Many researchers suspect the build-up of such plaques may be a cause of the memory robbing disease, although that theory has yet to be definitively proved.

The next step will be to investigate whether removal of brain amyloid translates into clinical benefit for patients at doses of the experimental drug, gantenerumab, that are well tolerated and safe, Roche said.

Gantenerumab, a biotech drug designed to bind to amyloid plaques in the brain and remove them, is being targeted at the early stages of Alzheimer’s with the hope it can slow progression of the disease while patients are still able to function.

The Phase I study of 16 Alzheimer’s patients tested gantenerumab at two doses against a placebo over six months of treatment.

The Roche drug led to a dose-dependent reduction of brain amyloid, while amyloid load increased in patients receiving a placebo, the company said.

Much larger trials and further study will be needed to fully understand just how gantenerumab works and whether it can stave off Alzheimer’s disease.

“These results and especially the rapidity of the effects observed on amyloid removal are very encouraging and pave the way for the development of a novel treatment for Alzheimer’s disease,” Luca Santarelli, head of Roche’s global neuroscience disease division, said in a statement.

Most companies working to develop Alzheimer’s treatments are focused on the disease in its later, more debilitating stages. Roche is approaching the disease far earlier.

“We know amyloid accumulates for 15 years before dementia, so why should you wait to remove it,” Santarelli told Reuters in an interview earlier this year.

Early, or prodromal, Alzheimer’s disease is a condition in which a person’s memory loss is worse than can be expected by the normal aging process, while their ability to engage in daily activities is not affected to the extent that dementia would be diagnosed.

Alzheimer’s disease is estimated to affect 25 million people around the world, with the number of diagnosed cases expected to rise dramatically with the aging of the enormous baby boom generation.

It is expected that the illness, which robs memory and ability to function, will affect about 63 million people by 2030, and 114 million by 2050 worldwide, according to forecasts cited by Roche.

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(Reuters)