| Those quoting the 30% figure may want to research where that figure comes from and what it actually means: “Derek Lowe has worked on drug discovery for over three decades, including on candidate treatments for Alzheimer’s. He writes Science’s In The Pipeline blog covering the pharmaceutical industry. “Amyloid is going to be — has to be — a part of the Alzheimer’s story, but it is not, cannot be a simple ‘Amyloid causes Alzheimer’s, stop the amyloid and stop the disease,'” he told Big Think. “Although the effect of the drug will be described as being about a third, it consists, on average, of a difference of about 3 points on a 144-point combined scale of thinking and daily activities,” Professor Paresh Malhotra, Head of the Division of Neurology at Imperial College London, said of donanemab. What’s more, lecanemab only improved scores by 0.45 points on an 18-point scale assessing patients’ abilities to think, remember, and perform daily tasks. “That’s a minimal difference, and people are unlikely to perceive any real alteration in cognitive functioning,” Alberto Espay, a professor of neurology at the University of Cincinnati College of Medicine, told KFF Health News. At the same time, these potentially invisible benefits come with the risk of visible side effects. Both drugs caused users’ brains to shrink slightly. Moreover, as many as a quarter of participants suffered inflammation and brain bleeds, some severe. Three people in the donanemab trial actually died due to treatment-related side effects.” https://bigthink.com/health/alzheimers-treatments-lecanemab-... And here’s a Lowe follow-up on hard data released later: https://www.science.org/content/blog-post/lilly-s-alzheimer-... |
It's not quite that simple, and the amyloid hypothesis doesn't claim it to be. It does, however, claim that it's the upstream cause of the disease, and if you stop it early enough, you stop the disease. But once you're already experiencing symptoms, there are other problem which clearing out the amyloid alone won't stop.
What’s more, lecanemab only improved scores by 0.45 points on an 18-point scale assessing patients’ abilities to think, remember, and perform daily tasks.
As I point out in another comment, the decline (from a baseline of ~3 points worse than a perfect score) during those 18 months is only 1.66 points in the placebo group, It's therefore very misleading to say this is an 18-point scale, so a 0.45 point benefit isn't clinically meaningful. A miracle drug with 100% efficacy would only achieve a 1.66 point slowdown.