Alzheimer's treatment almost within reach

Findings from an early trial of a new drug suggest it succeeded in partially blocking a protein which leads to damaging clumps seen in the brains of patients with Alzheimer's.

Now in phase-three trials, if the drug manages to slow down the cognitive decline which is a hallmark of Alzheimer's, it could become the first treatment to hit the market in decades bringing hope to millions.

Alzheimer's is a type of dementia—an irreversible, progressive brain disorder—which slowly destroys memory, thinking and behaviour in older adults. It is not a normal part of ageing.

According to the World Health Organization, 36 million people around the world suffer from some form of dementia, mostly Alzheimer's. The number is expected to double by 2030 to exceed 65.7 million, and to triple by 2050 to 115.4 million, if no effective treatment is found in the next few years.

Merck Research Laboratories, in the northeastern state of New Jersey, reports results of early human and animal trials of a drug called verubecestat, which targets the production of beta amyloid proteins which accumulate as brain plaques associated with the disease. "It's a summary of the discovery and early-stage profiling of what we hope is going to be a new therapy for Alzheimer's," team leader Matthew Kennedy said.

Slowing cognitive decline

The findings of the 32-subject human trial, primarily carried out to assess safety, showed that it safely and effectively reduces toxic amyloid proteins that clump together to become sticky plaques.

According to current understandings, these plaques result in neurodegeneration which manifests as memory loss, cognitive dysfunction and behavioural disruption.

The experimental treatment has proved to be promising and free of harmful side effects. This has raised hopes that an effective drug to treat the disease may become available in the market in the next two to three years depending upon the success of current trials.

"We are eagerly awaiting the results of the phase-three clinical trials," Kennedy said. "It is premature to speculate on availability." These trials will conclude in July 2017.

Earlier, researchers abandoned experiments with drugs that neutralised the enzyme linked to amyloid build-up, as these drugs had very toxic side effects, such as liver damage or further neurodegeneration.

But verubecestat has shown no such side effects, said Kennedy.

Researchers found that one or two doses of the compound were enough to lower protein levels without causing side effects.