In a day of mixed results for Alzheimer's research, researchers found that an experimental vaccine failed to prevent the disease's crippling dementia, but also noted that a drug once used to treat hayfever "significantly" improves the symptoms of memory loss. The two separate studies were both published in the Lancet [subscription required], and offer a telling reminder that in medical research progress against a disease is rarely straightforward. The first study treated patients who had already been diagnosed with Alzheimer's with a vaccine that
targeted the protein plaques that clump around brain cells in increasing numbers as Alzheimer's progresses. The theory was that dementia could be slowed or reversed once the plaques were cleared [HealthDay News]. However, the vaccine had no effect on the patients' slide into dementia, despite the fact that autopsies of patients who died during the study showed that the plaques had largely vanished.
The vaccine study's ...