- The Washington Times - Monday, March 28, 2005

There is nothing easy where Alzheimer’s is concerned — neither the research work nor the patient care. A memory disorder disease that affects nearly 5 million Americans and is expected to affect 14 million by 2050, its cause is unknown and treatment methods on the market are palliative at best.

But scientists in recent years have at least been able to report encouraging results from ongoing studies that could help determine the cause of the disease and provide a likely cure.

The clinical trials that must precede formal approval of new treatment drugs are done at sites around the country and involve human volunteers willing to help test new approaches.

Nine of these currently are under way at Georgetown University Medical Center’s Memory Disorders Clinic, a regional leader in the effort, which actively solicits recruits who meet the necessary guidelines. The clinic was founded in 1999 by Dr. Paul Aisen, professor of neurology and medicine and a prominent researcher in the field.

On the front lines, too, are therapists such as Elizabeth Cockey, who works in several Baltimore nursing homes to help moderately and severely afflicted patients lead better lives and keep the disease at bay. Ms. Cockey, author of a book about her experiences called “Gertrude’s Cupboard,” uses art projects to stimulate patients’ mental and physical capacities — a form of behavior modification she says can show results in a person within six months.

“When you do art, every part of the brain lights up,” she says. “We create new neurological pathways,” she claims, while acknowledging she has no empirical data to prove her findings — the kind of data that is the lifeblood of scientists like Dr. Aisen.

“In the field of Alzheimer’s, up until 1993 there were no treatments, while over the last 12 years five drugs have been approved by the [Food and Drug Administration],” he says. “That is a tremendous development, because we went from a disease always assumed to be untreatable to a disease that is clearly treatable.”

He was able last July to announce results in a so-called phase-two trial of a new drug called Alzhemed. The study, done in conjunction with a small Canadian company called Neurochem, showed that Alzhemed, a compound, could reduce the levels of a molecule in the brain called the amyloid peptide. That molecule is believed to be pivotal in the formation of Alzheimer’s.

“Many groups are focusing on this peptide,” he says. “If we want to change the course of the disease, we think we have to target that peptide. The majority of our efforts today are not at relieving symptoms, but targeting the peptide, either by clearing it from the brain or stopping its production in the brain.”

Treatments known today relieve symptoms, he notes, but don’t stop progression of the disease: “Like a painkiller for arthritis is not doing anything to protect the joint, but you are relieving symptoms.”

The so-called anti-amyloid strategies represented by the Alzhemed program were tried out successfully on 50 people — “the first demonstration that we were able to actually influence this causative molecule.” The next step is a phase-three trial involving 1,000 people from the United States and Canada that will take at least 18 months.

Determining whether a drug relieves symptoms is done with memory tests that can show an impact in a short time. But testing the value of a drug that might alter the disease’s progression requires monitoring subjects long enough to see a change in the course of the disease, Dr. Aisen explains.

The Georgetown Center offers clinical evaluations and treatment services for all kinds of memory impairment, of which Alzheimer’s is just one — but the most alarming and difficult one to treat. It also is the most costly, according to Dr. Aisen. “The economic impact of Alzheimer’s disease today is estimated at 100 billion dollars a year in the United States,” he says.

The center works in collaboration with the U.S. National Institutes of Health and private corporations to develop other strategies targeting the amyloid peptide. Some of the strategies involve setting up so-called model systems in the lab, using brain cells grown in culture dishes and then in mice.

The center also is one of 50 sites in the United States and Canada taking part in a $60 million five-year public-private project known as the Alzheimer’s Disease Neuroimaging Initiative due to begin next month. The study, instigated by NIH’s National Institute on Aging, will compare neuroimaging, biological and clinical information in participants with mild cognitive impairment and Alzheimer’s in order to make better use of these tracking methods.

“What they are trying to do is diagnose Alzheimer’s through scanning, which can’t be done yet,” explains Nancy Disan, program manager for the National Capital chapter of the nonprofit Alzheimer’s Association, the largest private funder of research for the disease. “Just now it is a ‘rule-out’ diagnosis — not a clear-cut one. The only way to verify [the disease] is an autopsy done on the brain after death, unlike cancer that you see under a microscope.

“The earlier we can catch the disease, the better we can treat it,” she says. “Right now we have to wait for a great amount of symptoms.”

The researchers’ ultimate goal is to learn how to stop the disease from progressing, Dr. Aisen told an interviewer for National Public Radio less than two years ago when the FDA approved the first drug — called memantine — to treat patients suffering from moderate to severe Alzheimer’s disease. Georgetown had been one of the test sites.

He sees as “promising” the number of new compounds now under study. Also under study is a natural product called huperzine A, which is extracted from a Chinese herb and taken in pill form. Another study employs a nicotine patch — the same one used by people who are trying to stop smoking. Lab experiments have shown that delivery of nicotine into the brain might favorably affect the progression of amyloid-related memory impairment, he explains.

“A number of trials have not worked out, but it is important to know what doesn’t work as well so people don’t take [medicines] unnecessarily that don’t help them,” says Neil Buckholtz, chief of the National Institute of Aging’s Dementia of Aging Branch. “You can’t really wait to see what happens to one. You must do a number in parallel.”

LOAD COMMENTS ()

 

Click to Read More

Click to Hide