How should drug effectiveness in Alzheimer’s disease be measured? Elizabeth Tracey reports


The amyloid hypothesis. That’s the idea that accumulation of a material called amyloid in the brain leads to Alzheimer’s disease. Acceptance of this idea has led the FDA to approve aducanumab, which reduces amyloid, but isn’t known to improve any symptoms of the disease. Caleb Alexander, an internal medicine expert at Johns Hopkins and a member of the FDA review panel, which voted against approval, explains.

Alexander: The pathogenesis of Alzheimer’s remains quite opaque. There’s an enormous amount that we don’t understand about the disease process. The amyloid cascade hypothesis for many years has sucked all the oxygen out of the room. There’s been an enormous investment in investigating products that are targeted to amyloid, at the expense of pursuing other potentially quite fruitful avenues of investigation.  :28

For now Alexander is concerned that desperate people will use aducanumab without evidence of its efficacy. At Johns Hopkins, I’m Elizabeth Tracey.