In the race to find a cure to Alzheimer’s disease, progress is moving forward. Then backward.
The Lancet, a British medical journal, is devoting this week’s issue to the causes and treatments for dementia, including one form, Alzheimer’s disease.
In one of two studies in the July 19th issue, an older drug, dimebon, improved the symptoms of Alzheimer’s.
At the Alzheimer’s Disease and Memory Disorders Center at Baylor College of Medicine in Houston, researchers studied the drug on 183 patients in Russia suffering with mild to moderate Alzheimer’s. In Russia, the drug was marketed as an antihistamine.
Patients received 20 milligrams of dimebon three times a day. Others received a placebo.
After six months, those on dimebon had shown improvement in their cognitive ability, measured by being able to track dates, comprehend instructions, and memorize word lists, among other tasks, compared with the placebo group.
In terms of measurable results, after six months the improvement on ADAS-cog test was 1.9 points. After one year, the dimebon patients showed a 6.9 point increase on the same test.
"We found treated patients were improved in their thinking abilities, their behavioral symptoms [and] their daily skills abilities, compared to people who took placebo," Dr. Rachelle S. Doody, the lead researcher, tells the Washington Post.
Dimebon is made by Medivation, a San Franciscso-based biopharmaceutical company which has just launched a phase III trial in the U.S. This is reported to be the first promising therapy in some time, and may be added to names such as Aricept, Namenda and Exelon.
In another study the results were not so promising. The Memory Assessment and Research Centre at Moorgreen Hospital in Southampton, UK, studied 80 Alzheimer’s patients, vaccinated with an experimental drug AN1792.
Treatment with the drug showed a reduction in the number of amyloid protein plaques in the brains of Alzheimer’s patients and in some cases a complete removal of plaque. That is the substance that is believed to clog the communication channels between nerves in the brains of Alzheimer’s and dementia patients.
The bad news is that the patients continued to deteriorate, even following the plaque removal. It does tell researchers that plaque removal is not sufficient on its own to cure Alzheimer’s, but that the forces that lead up to plaque formation should be the focus of future research.
There are about 4.5 million Americans suffering from Alzheimer’s disease where the brain’s ability to store memory and carry out everyday tasks is interrupted. A rush is on to find a cure as the population ages and incidents increase. At age 65, one in twenty are thought to be affected. That number jumps to half of those who reach the age of 85 and older.
A recent study published in Neurology, showed that those who exercised had reduced brain shrinkage, equated with Alzheimer’s and dementia. #