In a high-stakes showdown between weight-loss drug developers, Novo Nordisk (NVO) suffered a dramatic sell-off Monday after its much-anticipated next-generation obesity therapy, CagriSema, failed to outperform Eli Lilly’s (LLY) tirzepatide in a head-to-head clinical trial.
The Danish pharmaceutical giant reported that patients taking CagriSema achieved an average weight loss of 23% after 84 weeks of treatment. While objectively impressive, the figure fell short of the 25.5% weight loss observed in patients taking Eli Lilly’s tirzepatide, the active ingredient in its blockbuster drugs Zepbound and Mounjaro.
Investors, who had pinned high hopes on CagriSema to extend Novo Nordisk’s dominance in the rapidly growing obesity treatment market, responded swiftly and harshly.
Shares of Novo Nordisk closed Monday at $39.63, down 16.43%—the stock’s lowest level since 2021. Trading volume surged to 94.9 million shares, approximately 343% above the stock’s three-month average volume of 21.4 million shares. The steep decline erased a significant portion of the gains the company had accumulated on the back of its earlier success with Wegovy.
The contrast with its primary competitor could not be starker. Eli Lilly shares climbed 4.86% to close at $1,058.46, while Novartis (NVS) also gained 1.25%, as investors reassessed the competitive landscape in the GLP-1 drug space. The broader market indexes retreated, with the S&P 500 slipping 1.04% to 6,838 and the Nasdaq Composite falling 1.13% to finish at 22,627.
Following the trial results, Deutsche Bank downgraded Novo Nordisk from “Buy” to “Hold,” citing the drug’s underwhelming performance in the direct comparison.
Novo Nordisk, which went public in 1981 and has delivered a staggering 24,669% return since its IPO, now faces mounting questions about its strategic direction. The company had already warned earlier this month that 2025 sales could decline by 5% to 13%, putting additional pressure on CagriSema to deliver positive news.
In a statement, Novo Nordisk said it remained “pleased with the weight loss of 23% for CagriSema” and confirmed plans to proceed with a higher-dose trial of the combination drug, which combines the amylin analog cagrilintide with a GLP-1 receptor agonist. However, for now, the data suggests that while CagriSema is undeniably effective, it may not be the game-changer investors had hoped for—especially with Eli Lilly’s tirzepatide setting a higher bar.
For investors, the path forward looks uncertain. Novo Nordisk must now grapple with whether it can defend its leadership in diabetes and obesity care, or whether it needs to look beyond these categories for future growth. As CagriSema’s prospects dim, the rebound investors were counting on may take considerably longer to materialize.
