(The New Yorker) – A new definition of Alzheimer’s includes people without symptoms. Experts are fiercely divided over whether that makes sense—and whether the new drugs really help.

These high hopes rest largely on two developments. First: drugs. Since 2021, the Food and Drug Administration has approved three antibody treatments meant to slow the disease’s progression. All target amyloid, a protein fragment that can accumulate into the plaques that have long been associated with Alzheimer’s and that many researchers believe plays an important role in its development. Two drugs—lecanemab, sold as Leqembi, and donanemab, sold as Kisunla—are on the market and are covered by Medicare.

The second development concerns diagnosis. Until recently, measuring amyloid levels in living patients required expensive PET scans or invasive spinal taps. Blood tests developed over the past five years approach the accuracy of those methods. (Read More)