A panel of Alzheimer's experts this week has been fleshing out the first comprehensive plan by the U.S. Department of Health and Human Services (HHS) to fight Alzheimer's disease, an effort mandated by the National Alzheimer's Project Act signed into law by President Barack Obama last year.

The law called for the government to create a blueprint to beat Alzheimer's but provided no new money for the effort.

More than 5 million Americans suffer from Alzheimer's, a brain disease that causes dementia and affects primarily elderly people. Some experts estimate the disease costs the United States more than $170 billion annually to treat.

Australia, France and South Korea already have comprehensive Alzheimer's plans, and global experts have been urging the United States to take a leadership role.

"We want to demonstrate that as a country we are committed to addressing this issue," Dr. Howard Koh, assistant secretary for health at HHS, told Reuters in a telephone interview.

"We know the projected number of patients is expected to rise in the future. We know there are far too many patients who are suffering from this devastating condition and it is affecting them and their caregivers," Koh said.

The U.S. plan is meant to galvanize efforts to fight the fatal disease that robs victims of their ability to think and drains the resources of family caregivers.

But some experts say the 2025 deadline is unrealistic.

"No one set a deadline for the 'War on cancer' or in the fight against HIV/AIDS. We make progress and we keep fighting. The same should be true for Alzheimer's," said Dr. Sam Gandy, an Alzheimer's researcher at Mount Sinai School of Medicine.

"In my mind, that provides the unfortunate sense that we will have 'failed' if we don't have a cure by 2025."

When U.S. President Richard Nixon declared war on cancer in 1971 and signed the National Cancer Act, the idea was to dedicate the same kinds of funds and resources to cancer as had been spent on splitting the atom.

In the 30-year fight against AIDS, it was only last November, with many effective treatments already in hand, that U.S. Secretary of State Hillary Clinton set a goal for an AIDS-free generation, something she said "would have been unimaginable just a few years ago."

By contrast, the National Alzheimer's Project Act provides no new money. And while a few drug companies have compounds in clinical trials, researchers say they are just starting to understand the disease, which develops silently for 15 to 20 years before any memory problems begin to show.

"This means that if we had, today, already in hand, the funding, recruitment and the perfect drug, the trial would still take 15 to 20 years," Gandy said.

Despite costly efforts, no drug has been found that can keep the disease from progressing. Some researchers fear drug companies will give up entirely.

The latest blow came on Tuesday, when Pfizer Inc said it would end its collaboration with Medivation Inc after the drug Dimebon failed to improve thinking ability in a late-stage trial.

"Our best shot is not at a cure but at prevention, and prevention trials for Alzheimer's will be larger, more time-consuming and more expensive than any prevention trials ever undertaken," Gandy said in an e-mail.

UNDERSTANDING THE DISEASE

The group Alzheimer's Disease International estimates there are now 37 million people with the disease worldwide. As the population ages, that number will increase to 66 million by 2030, and to 115 million by 2050, the group said.

Koh said organizing efforts around a single strategic plan will help speed treatment, expand patient support and improve care for patients.

Part of the problem is that scientists are just beginning to sort out which changes in the brain are linked with Alzheimer's and which are related to other forms of dementia.

On Wednesday, the National Institute on Aging (NIA), part of the U.S. government's National Institutes of Health, published final recommendations in Alzheimer's & Dementia: The Journal of the Alzheimer's Association that should help pathologists do a better job of characterizing these differences.

The new NIA guidelines are the first since 1997, and they differentiate between memory changes diagnosed by doctors while a patient is still living and the brain changes that pathologists can see in an autopsy.

One of the hallmarks of Alzheimer's is the presence of so-called plaques and tangles in the brain that are used to identify the disease.

Very often - about 30 percent of the time - brain autopsies reveal Alzheimer's-related plaques and tangles in people who had no sign of dementia while they were living, said Dr. Creighton Phelps of the NIA's division of neuroscience.

"We are missing something," Phelps said.

INVESTMENT NEEDED

So far, U.S. investment in the search for Alzheimer's treatments has fallen short of what the nation spends on other chronic diseases, such as cancer and heart disease.

William Thies, chief medical and scientific officer of the Alzheimer's Association, said the National Institutes of Health's budget for Alzheimer's research is a little over $450 million. "If you add in private sector money, that is close to $500 million," Thies said.

That compares to the roughly $6 billion spent by the NIH on cancer and more than $4 billion on heart disease annually, Thies said.

Thies said those investments have paid off in significant advances in treatments for both conditions, and he thinks the same could happen with Alzheimer's.

Koh said more public funding would be "tremendous," but just the act of coordinating various Alzheimer's efforts should focus research and stimulate funding from the private sector.

George Vradenburg, chairman of the advocacy group USAgainstAlzheimer's and a member of the HHS Advisory Council on Alzheimer's Research, had been pushing for a 2020 deadline for an Alzheimer's cure, but he called the 2025 goal a "major step forward."

"If we set a national goal of stopping this disease by 2025, I think there is no question that this administration will seek additional resources to ensure we are on a path to get that done," Vradenburg said.

(Editing by Michele Gershberg and Will Dunham)

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