Scientists develop vaccine that could ease Alzheimer's torment

In tests, the jab protected against the erosion of balance and co-ordination caused by a dementia-like illness.

Although existing pills can delay the progress of Alzheimer's, their effects are mild and the disease soon takes its course.

With 500 cases of Alzheimer's diagnosed every day as people live longer, and a global epidemic predicted by 2050, there is a desperate need for new treatments.

The latest research focuses on a key brain protein called tau.

In Alzheimer's patients, a rogue version of the protein forms tangles inside brain cells, which shrink and die, leading to memory loss and, eventually, the loss of the ability to walk, talk and even swallow.

Researchers from New York University-Medical Centre have created a vaccine that targets abnormal-tau proteins and breaks them up, stopping them from damaging the brain.

When it was given to mice suffering from a dementia-like illness, their balance and co-ordination deteriorated much more slowly than if they had not been vaccinated.

The animals also had fewer tau tangles in the part of the brain responsible for memory and understanding, suggesting the jab may also protect against memory loss.

Researcher Dr Einar Sigurdsson-said: "This approach may have extensive therapeutic implications because you can specifically target the problematic protein.

"Tau aggregates inside the cell, making it especially difficult to develop a therapy to target and clear them from the cell."

Dr Sigurdsson, whose findings are published in the Journal of Neuroscience, now plans to look at whether the jab improves memory.

However, while the research is promising, the extensive testing needed means that such a vaccine is around a decade away from the market.

Such a jab would most likely be given to those in the early stages of the disease, in an effort to slow or halt its progression.

In addition, it is likely the best results would be achieved by combining it with a second drug, capable of targeting amyloid, another toxic protein found in the brains of Alzheimer's patients.

Dr Sigurdsson said: "It is likely there's a synergism in the pathology. Amyloid pathology may cause tau pathology and tau pathology might cause amyloid pathology.

"What you have is a vicious cycle. If you can target both proteins, you'll likely have a more efficacious treatment."

Several drugs capable of tackling amyloid are already in development, including a vaccine which has just started human trials in Switzerland.

British experts welcomed the U.S. breakthrough.

Harriet Millward, of the Alzheimer's Research Trust, said: "These findings are exciting and could lead to ways to treat or even prevent Alzheimer's disease.

"However, a lot more research needs to be done before the vaccine could possibly be developed into a safe and successful treatment for humans.

"With 700,000 people with dementia in the UK - a number forecast to double within a generation - we urgently need to find ways to halt this devastating disease.

"We desperately need to increase funding for research to find an answer to Alzheimer's."