GLP-1's Alzheimer's Hopes Dashed by Novo Trial Failures, Shares Plunge

Novo Nordisk (NVO) shares tumbled in premarket trading on Monday after the Danish drugmaker announced that its oral semaglutide-a pill version of its blockbuster diabetes and obesity drugs Ozempic and Wegovy-failed to slow Alzheimer's disease progression in two large phase 3 trials. The EVOKE and EVOKE+ studies, which aimed to explore a potential new use for the GLP-1 drug, did not demonstrate superiority over placebo in reducing disease progression, as measured by the Clinical Dementia Rating – Sum of Boxes (CDR-SB) score. While semaglutide improved Alzheimer's-related biomarkers, the results did not translate into meaningful clinical benefits, leading Novo to discontinue a planned one-year extension of the trials.

The news sent Novo Nordisk's stock down nearly 10% in U.S. premarket trading and over 8% in European markets according to market data. The setback adds to a challenging year for the company, which has seen its shares lose more than 50% of their value in 2025 amid intensifying competition in the weight-loss market and a strategic shift toward aggressive pricing cuts to maintain market share. The Alzheimer's trial failure also dashes hopes for a lucrative new indication for semaglutide, which has already become a cornerstone of Novo's revenue.

Analysts had viewed the Alzheimer's trials as a high-risk, high-reward opportunity. While some speculated that GLP-1 drugs might influence neurodegenerative pathways, the lack of statistically significant results has raised questions about the therapeutic potential of semaglutide beyond metabolic diseases. "The evoke and evoke+ trials did not confirm superiority of semaglutide versus placebo in the reduction of progression of Alzheimer's disease," the company stated in a recent announcement. Full results are expected to be presented at the Clinical Trials on Alzheimer's Disease conference in December 2025 according to company reports.

The market reaction extended beyond Novo. Eli Lilly (LLY), a key rival in the GLP-1 space, saw its shares fall 5% as investors reassessed the broader prospects for the class of drugs in neurology applications. Conversely, Biogen (BIIB) shares rose 2.7% in premarket trading, reflecting shifting dynamics in the Alzheimer's treatment landscape. Morgan Stanley analysts also adjusted their outlook, raising Eli Lilly's stock price target to $1,290 amid continued growth in the GLP-1 market.

Novo Nordisk's struggles highlight the risks of over-reliance on a single therapeutic platform. While semaglutide has dominated obesity and diabetes care, the company faces mounting legal, regulatory, and competitive pressures. Recent developments-including Denmark's compensation of patients for vision loss linked to Wegovy and Ozempic, and a broader price war in the GLP-1 market-have further complicated its path forward.