Skip to content
My WebMD Sign In, Sign Up

Alzheimer's Disease Health Center

Font Size

Alzheimer's Cure Elusive Despite Progress

Ronald Reagan's struggle shows how far we've come, how far we have to go.

Tomorrow's Plaque Fighters continued...

This isn't science fiction any more. Several companies are racing to develop this strategy, known as passive immunization or passive antibody transfer.

"It works in the mouse model," Gandy says. "It should be effective."

The second idea is to keep plaque from forming clumps. Amyloid gets particularly sticky when it combined with two substances: sugars and metals (especially zinc). Drugs that block both of these combinations are in the pipeline. And they work in mice, Gandy says.

The third idea -- and the one closest to reality -- involves new uses for existing drugs. Amyloid doesn't just happen. It's the result of a complex biochemical process. The process stops without a key set of enzymes.

It's recently become clear that some of the cholesterol-fighting drugs called statins block these enzymes. Data from trials of one of these drugs -- Lipitor -- suggest that people taking the drug to treat high cholesterol have a lower risk of Alzheimer's disease. The National Institute on Aging (NIA) is conducting a large clinical trial to see whether another of these drugs, Zocor, actually prevents Alzheimer's.

The NIA is also looking at another class of drugs capable of blocking amyloid production. It's the NSAIDs or nonsteroidal anti-inflammatory drugs -- the same class to which aspirin and ibuprofen belong. One of these drugs, Ansaid, may be particularly effective against amyloid, Gandy says.

If these drugs already exist, why aren't they being used? The reason is that amyloid plaques are notoriously hard to detect until Alzheimer's disease is well under way.

That, too, is changing. Gandy says that new imaging techniques called PET scans will allow doctors to see tiny spots of amyloid.

"This might be useful for very early diagnosis of people getting Alzheimer's disease, decades before symptoms show up," Gandy says. "And it will help with developing prevention drugs, because it will let you see what is going on."

Many people who don't think plaque is the No. 1 bad guy have another villain in mind. These are the tangled fibers in the brains of Alzheimer's patients. It's been hard to work on anti-tangle drugs, because there's no good animal model. But progress is being made, Gandy says.

Today's Alzheimer's Disease Treatments

While waiting for tomorrow, a lot of exciting Alzheimer's treatments are available today.

Currently available drugs slow Alzheimer's process. Patients who were on a sharp decline often stabilize. Today, there are several ways to treat Alzheimer's disease:

  • Aricept, Exelon, and Reminyl. These are the cholinesterase inhibitors. Cholinesterase breaks down an important brain chemical called acetylcholine. These drugs keep this from happening. Unfortunately, this doesn't stop brain cells from dying. About half of the patients who take these drugs see a modest improvement in mental function. (Tacrine, the first member of this class of drugs, now rarely is used because it sometimes causes liver damage.) In April 2005, Reminyl's label was changed to include information about the deaths of 13 elderly patients who were taking the drug during a study. The deaths were due to various causes, including heart attack and stroke.

  • Namenda, approved in October 2003, is the newest kind of Alzheimer's drug. It's called an NMDA receptor antagonist. The NMDA receptor is a kind of dimmer switch that controls the actions of a brain chemical called glutamate. Glutamate plays a major role in learning and memory. Too much of it kills brain cells. Too little makes them grind to a halt. Namenda helps balance glutamate levels.

  • Vitamin E. Everybody's brain is under constant attack from destructive oxygen molecules called free radicals. We've evolved effective ways to fend off these attacks. But Alzheimer's disease and the normal aging process seems to lower these defenses. Antioxidant compounds -- especially vitamin E -- may reinforce this crumbling line of defense.

Today on WebMD

alzheimer's disease warning signs
ARTICLE
Alzheimers Overview
SLIDESHOW
 
Best Memory Boosting Games
ARTICLE
mri scan of human brain
QUIZ
 
senior man
ARTICLE
daughter and father
ARTICLE
 
Making Diagnosis
Article
Colored mri of brain
ARTICLE
 
Close up of elderly couple holding hands
VIDEO
senior woman with lost expression
ARTICLE
 
Woman comforting ailing mother
ARTICLE
Alzheimers Dementia
ARTICLE