Alzheimer's vaccine helped slow the disease: Study
A vaccine against the disease that was dumped because it caused dangerous brain inflammation did help slow the disease in some patients, researchers have said.health and fitness Updated: May 22, 2003 03:13 IST
A vaccine against Alzheimer's disease that was dumped because it caused dangerous brain inflammation did help slow the disease in some patients, Swiss researchers reported on Wednesday.
Other experts said the study, published in the journal Neuron, showed the concept of vaccinating people against Alzheimer's has merit.
Alzheimer's affects 15 million people around the world and 4 million in the United States.
The disease gradually destroys the brain, causing memory loss and confusion that becomes so severe that patients cannot care for themselves. There is no cure, although some drugs can temporarily slow the progression of the disease.
An experimental vaccine, AN-1792, targets the beta amyloidproteins associated with Alzheimer's. These proteins form the characteristic brain-clogging plaques found in patients.
The vaccine generated antibodies against beta amyloid, Christoph Hock and colleagues at the University of Zurich found.
"Patients with high levels of antibodies were essentially protected from disease progression over the one year study period," said Dr. Roger Mitsch, who led the study.
"This is the first time that antibodies against beta amyloid were shown to be effective in slowing the course of Alzheimer's disease," he said in a statement.
The vaccine trials were stopped a year ago after 17 of 300 patients being tested developed a life-threatening inflammation of the brain called meningoencephalitis.
The Zurich researchers looked at 30 of the 300 patients, including three with encephalitis.
"Twenty patients generated antibodies against beta-amyloid," they wrote in their report. These 20 all showed a slowdown of disease -- including two who developed encephalitis.
"This article shows that the concept of vaccination is alive," Bengt Winblad and Kenneth Blum of Sweden's Karolinska Institute wrote in a commentary.
The patients were not cured, the researchers note -- probably because several other proteins are also involved in the brain damage seen in Alzheimer's.
The trial of AN-1792, which was developed by Ireland's Elan Corp. (ELN.I) in partnership with the company now known as Wyeth (WYE.N), was suspended in March 2002.