TL;DR
For years the leading idea about Alzheimer's has been simple: clear the sticky amyloid plaque out of the brain and the disease should slow. A drug built to do that more gently has just delivered one of the clearest tests yet, and the answer was sobering. In a 542-person, 18-month trial, Acumen Pharmaceuticals' sabirnetug lowered plaque on brain scans but did not slow the loss of memory, thinking or everyday ability, and the company is ending it. That is a loss for one drug, not for the search. It sharpens the question every plaque drug now has to answer, which is what it adds beyond a cleaner scan, and it hands the spotlight to the very next tests, all due in the third week of November in Boston: a pill tested in 1,535 people, a drug aimed at the brain's tangles instead of its plaques, and a pill meant to calm the stress hormone inside brain cells. If any of them works, treating Alzheimer's could start to look less like a monthly infusion and more like a daily tablet. For the odds on an Alzheimer's pill and a timeline of the trials that could get one to patients, subscribe.
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