Summary
The recetn clinical results suggest that plaque removal is not enough to halt progressive neurodegeneration in Alzheimer Disease and prompt some intriguing challenges to the amyloid hypothesis.
Analysis
Plaque removal is not enough to halt progressive neurodegeneration in Alzheimer Disease, by Holmes C, Boche D, Wilkinson D, Yadegarfar G, Hopkins V, Bayer A, Jones R, Bullock R, Love S, Neal J, Zotova E, Nicoll J. This hypothesis suggests that clearance of amyloid plaques from brains of AD patients does not prevent progressive neurodegeneration. The hypothesis is based on long-term clinical follow-up, post-mortem neuropathological examination, or both, that was performed on patients who had entered a phase I randomized, placebo-controlled trial of immunization with Aβ42 (AN1792, Elan Pharmaceuticals) six years after the immunization clinical trial. Long-term clinical follow up showed no evidence of improved survival, no improvement in the time to severe dementia despite lower Aβ load compared to an unimmunized control group that was matched for age at death. These results suggest that plaque removal is not enough to halt progressive neurodegeneration in Alzheimer Disease and prompt some intriguing challenges to the amyloid hypothesis.
