For the first time, researchers are reporting that a treatment might help stabilize Alzheimer's disease for as much as three years, although the evidence is weak and in only four patients.
The drug is Gammagard, made by Baxter International Inc. Doctors say that four patients who have been receiving the highest dose for three years showed no decline on memory and cognition tests.
A dozen others on different doses or shorter treatment times didn't fare as well.
The study was far too small to prove the drug works. A more rigorous one involving 400 patients will give results within a year.
Still, the findings from the small study encouraged doctors at the Alzheimer's Association International Conference in Vancouver, British Columbia, where they were presented on Tuesday.
"It's tantalizing. If you were to pick out four people with Alzheimer's disease, the likelihood that they would perform the same on standardized tests three years later is very, very tiny," said William Thies, the association's scientific director.
"We shouldn't get euphoric and we shouldn't get unreasonable enthusiasm, but this is a positive piece of data," he said.
Gammagard is intravenous immune globulin, or IVIG — multiple, natural antibodies culled from donated blood. These antibodies may help remove amyloid, the plaque that clogs patients' brains, sapping memory and ability to think.
Other doctors warned against over-optimism. Many previous drugs looked good until tested in large, definitive studies.