---
title: "Biogen Slumps As Alzheimer's Study Leaves 'More Questions Than Answers'"
type: "News"
locale: "en"
url: "https://longbridge.com/en/news/292658953.md"
description: "On Tuesday, Biogen and Ionis announced that their Alzheimer's treatment aimed at targeting tau proteins resulted in a 26% reduction in cognitive decline within an 18-month period. However, despite this positive outcome, Biogen experienced a decline in its stock value as the Alzheimer's study raised uncertainties rather than providing clear answers."
datetime: "2026-07-14T16:50:16.000Z"
locales:
  - [zh-CN](https://longbridge.com/zh-CN/news/292658953.md)
  - [en](https://longbridge.com/en/news/292658953.md)
  - [zh-HK](https://longbridge.com/zh-HK/news/292658953.md)
---

# Biogen Slumps As Alzheimer's Study Leaves 'More Questions Than Answers'

On Tuesday, Biogen and Ionis announced that their Alzheimer's treatment aimed at targeting tau proteins resulted in a 26% reduction in cognitive decline within an 18-month period. However, despite this positive outcome, Biogen experienced a decline in its stock value as the Alzheimer's study raised uncertainties rather than providing clear answers.

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