--- title: "Biogen Shares Jump 10% After Advancing Alzheimer's Tau Drug" type: "News" locale: "en" url: "https://longbridge.com/en/news/286480030.md" description: "Biogen's shares surged 10% after the company announced progress with its Alzheimer's drug diranersen, despite a mid-stage study not meeting its primary goal. The drug targets tau, a protein linked to Alzheimer's, and showed potential benefits in slowing disease progression. Biogen's head of development highlighted a promising combination of tau reduction and cognitive benefits. This development may reignite interest in tau-targeting treatments, contrasting with current therapies focused on amyloid. Biogen's stock has risen 16% this year, reflecting investor optimism following setbacks in other tau-focused studies." datetime: "2026-05-14T23:19:13.000Z" locales: - [zh-CN](https://longbridge.com/zh-CN/news/286480030.md) - [en](https://longbridge.com/en/news/286480030.md) - [zh-HK](https://longbridge.com/zh-HK/news/286480030.md) --- # Biogen Shares Jump 10% After Advancing Alzheimer's Tau Drug Biogen is moving ahead with its experimental Alzheimer's drug diranersen after a mid-stage study showed promising, though still inconclusive, signs of benefit. The medicine targets tau, a toxic protein that forms tangles inside brain cells and is believed to play a critical role in Alzheimer's disease. Although the study did not meet its predetermined primary goal, Biogen said the data were strong enough to support advancing diranersen into a late-stage trial, giving investors a possible new angle on a disease area where drug development has remained highly difficult. Biogen said patients who received diranersen saw their disease worsen more slowly across every dose level, with the smallest dose showing the most benefit. Priya Singhal, Biogen's head of development, said the company believes it has seen an unprecedented and compelling combination of tau reduction and potential cognitive benefit. The result is notable because current approved Alzheimer's treatments, Biogen and Eisai's Leqembi and Eli Lilly's Kisunla, focus on lowering amyloid rather than tau, and both have shown modest benefits in slowing the disease. For investors, the update could possibly reopen interest in tau as a treatment target after years of setbacks across the industry. Researchers have long debated whether amyloid or tau should be the main focus, with amyloid believed to accumulate long before symptoms appear while tau buildup is considered more closely linked to Alzheimer's symptoms. Biogen shares rose as much as 10% in pre-market trading and had gained 16% this year through Wednesday's close, while the company's decision to move diranersen forward comes after other tau-focused efforts, including Johnson & Johnson's late-November study, failed to arrest patient decline. ### Related Stocks - [BIIB.US](https://longbridge.com/en/quote/BIIB.US.md) - [BBH.US](https://longbridge.com/en/quote/BBH.US.md) - [FBT.US](https://longbridge.com/en/quote/FBT.US.md) - [XBI.US](https://longbridge.com/en/quote/XBI.US.md) - [LABU.US](https://longbridge.com/en/quote/LABU.US.md) - [ARKG.US](https://longbridge.com/en/quote/ARKG.US.md) - [IBB.US](https://longbridge.com/en/quote/IBB.US.md) - [PBE.US](https://longbridge.com/en/quote/PBE.US.md) - [4523.JP](https://longbridge.com/en/quote/4523.JP.md) - [LLY.US](https://longbridge.com/en/quote/LLY.US.md) - [JNJ.US](https://longbridge.com/en/quote/JNJ.US.md) ## Related News & Research - [BUZZ-Street View: Skeptical on experimental Alzheimer's drug, awaits full data](https://longbridge.com/en/news/286558948.md) - [TD Cowen Sticks to Their Buy Rating for Biogen (BIIB)](https://longbridge.com/en/news/286442023.md) - [Biogen to advance experimental Alzheimer’s drug despite mid-stage trial miss](https://longbridge.com/en/news/286407083.md) - [Apellis Completes Biogen Merger and Goes Private](https://longbridge.com/en/news/286424730.md) - [](https://longbridge.com/en/news/286787081.md)