Why is a new Alzheimer’s drug so controversial? Elizabeth Tracey reports


Is amyloid, a substance that accumulates in the brains of people with Alzheimer’s disease, the cause of the disease or simply a bystander? No one knows, and that’s why an FDA advisory panel voted against approving a new drug to treat Alzheimer’s, because it relies on reducing amyloid. Caleb Alexander, an internal medicine expert at Johns Hopkins and one member of the advisory panel, describes what’s known.

Alexander: There have been more than two dozen studies that have failed that have been focused on trying to reduce amyloid levels. Amyloid is implicated somehow in the disease process but whether or not it’s a valid surrogate is a far different question. And one of the many surprises of the FDA’s recent decision is that they’ve decided to hang their hat on amyloid as a reasonable surrogate. Now Biogen has up to nine years to produce a confirmatory trial.  :31

At Johns Hopkins, I’m Elizabeth Tracey.