Alzheimer's disease: the method of early diagnosis has been tested
An effective marker for the diagnosis of Alzheimer's disease is proposedDmitry Tselikov, Compulenta
Tests of a new contrast agent for positron emission tomography (PET) AV-45 (aka Florbetapir F18), which took $60 million and five years, ended with complete success.
Examination of people suffering from Alzheimer's disease shortly before death showed the same amount of toxic beta-amyloid proteins as an autopsy after death.
"The results are very encouraging," project manager Michael Weiner from the University of California, San Francisco (USA) announced at the conference of the Alzheimer's Association in Honolulu. "They indicate the existence of a very good, statistically significant correlation between the brightness of images and the amount of amyloid at autopsy."
The marker was developed by Avid Radiopharmaceuticals. The tests were conducted by the US National Institute of Aging.
To this day, only an autopsy can confirm that a person suffered from Alzheimer's disease. Since the living are not yet opened, doctors have to exclude many other factors that can lead to memory loss: stroke, tumor, alcoholism when diagnosing the disease. The task is very difficult.
Therefore, many scientists are looking for biomarkers that can make life easier for doctors. Some are trying to link the change in brain volume with the disease, others — the amount of proteins in the cerebrospinal fluid. The main goal is to learn how to diagnose Alzheimer's as early as possible. Recently, British scientists called the earliest sign of the development of the disease an increase in the blood protein clusterin, but they still have many years of checks and improvements ahead of them. Here, the result is obvious, and it can already be implemented in medical practice.
Two isotope indicators were tested. The first, Pittsburgh Compound B (PIB), relies on carbon-11, which has a half-life of only 20 minutes. But it can only be obtained in a cyclotron (a kind of particle accelerator), and then quickly injected into the patient. Very few hospitals can afford this. Florbetapir F18, in turn, relies on fluoride-18, which lives for two hours, so it can be brought to a medical facility from another place.
Tests of the marker based on fluoride-18 are also being completed by General Electric and Bayer. The future global market of isotope indicators is estimated at $1-5 billion. Its value depends on whether pharmaceutical companies will be able to develop effective treatments, because otherwise early diagnosis will not make any sense. Current medications only temporarily relieve symptoms, but they cannot prevent the development of the disease. Worldwide, this type of dementia affects 26 million people a year.
Prepared by Reuters: Avid amyloid tracer hits target in Alzheimer's studyPortal "Eternal youth" http://vechnayamolodost.ru