Small Study Targets Alzheimer's Brain Plaque
Researcher Says Method Needs More Study, Not Ready for Treatment
June 20, 2005 -- A very small, short-term study may lead to a new approach to treating Alzheimer's disease.
Researchers found that an experimental treatment called IVIg (intravenous immunoglobulin) improved mental function in Alzheimer's patients.
IVIg is a "cocktail" of antibodies derived from donated human blood. Its antibodies include those that fight beta-amyloid, a key ingredient in the brain plaque associated with Alzheimer's disease.
The news does not amount to a new treatment, say the researchers, who included Marc Weksler, MD, of Cornell University's medical school.
These results clearly justify further examination in a larger study, says Weksler, in a news release. "However, our evidence does not recommend IVIg as a current treatment for Alzheimer's disease."
The study was presented in Washington, at the Alzheimer's Association's International Conference on Prevention of Dementia.
The study included eight people with mild to moderate Alzheimer's disease. They received infusions of IVIg for six months.
Participants took cognitive tests before and after the six-month treatment. They either received infusions once a week, once every two weeks, or once a month.
Mental Function Stabilized
After each infusion, patients' blood samples showed higher levels of antibodies that target beta-amyloid. The antibody increase reflected the dose of IVIg, say Weksler and colleagues.
Successive treatments brought increases in beta-amyloid antibodies in the weekly or every-other-week groups, but not in the monthly group. That may reflect the shorter life of such antibodies in people with Alzheimer's disease, say the researchers.
In addition, samples of spinal fluid taken from patients showed a drop in beta-amyloid. On average, beta-amyloid in the fluid dropped 45%, more than previously observed, says a news release.
Scores on mental tests either held steady or improved for the participants during the study.
Until more research is done on more patients it's impossible to tell the true effect of IVIg on Alzheimer's progression.