Scientists led by a team from the University of Edinburgh are launching a STG50 million research project to develop a drug to fight Alzheimer's.

A new approach to developing Alzheimer's drugs is at the heart of a STG50 million ($A91.27 million) European research project which could mark a turning point in the fight against the disease.

Scientists led by a team from the University of Edinburgh will attempt to find reliable biomarkers in patients that can be used to spot very early signs of the disease.

At the same time another arm of the study, running in parallel, will look for drugs that might help those individuals at highest risk.

The evolving strategy will aim to fit particular drugs to patients with specific characteristics, identified through brain scans, genetic make-up, or biomarkers in the blood or cerebro-spinal fluid.

In this way the researchers hope to highlight treatments that can be given long before a patient develops full-blown symptoms of Alzheimer's.

The five-year European Prevention of Alzheimer's Dementia (Epad) project will establish a European-wide register of 24,000 participants.

Of these, some 1500 will be invited to take part in Phase II drug trials.

"I'm very, very hopeful about this initiative," said Epad co-ordinator Professor Craig Ritchie, from the University of Edinburgh.

"What we're beginning to understand is that the disease is probably beginning to develop decades before the onset of symptoms in someone's 30s, 40s or 60s.

"We have to see if we can produce a profile of an individual who is more likely to progress and then look for an intervention.

"A lot of drugs that have been tested already haven't made it through the various phases to get to the market. One of the arguments is if you want to manage the course of Alzheimer's you have to treat patients at a very early stage.

"Historically we've tended to get everything ready beforehand, fire the starting gun, and just wait. Five years on we get the data and it's a case of 'oh damn, it doesn't work'.

"The new research will be evolving. If something's not working in population A but working in population B, we'll recruit more people from population B. The trial continually evolves to get the best chance of success."

Some drugs that have failed when used to treat symptomatic Alzheimer's might turn out to be effective at an earlier stage of the disease, he said.

It was also possible that drugs currently used to treat other conditions, such as inflammatory disorders, may be shown to combat early-stage Alzheimer's.