Novo Nordisk stock skidded Tuesday after Eli Lilly's weight-loss drug outperformed Novo's rival medication in a first-of-its-kind study.
The study examined electronic health records for more than 41,000 patients who started taking Lilly's tirzepatide or Novo's semaglutide between May 2022 and September 2023 for diabetes treatment. After a year, patients on tirzepatide were three times more likely to have lost at least 15% of their body weight.
The study comes with some caveats. Truveta Research, which performed the analysis, noted the results have yet to be peer reviewed. Further, there haven't yet been randomized studies pitting Lilly's tirzepatide against Novo's semaglutide. Lilly is now running a study and hopes to wrap in 2025.
Still, on today's stock market, Novo Nordisk stock fell 2.4% to 101.43. Eli Lilly stock closed flat at 591.60.
Novo Nordisk Stock Falters On New Study
Tirzepatide and semaglutide both belong to a class of drugs that mimic a gut hormone called GLP-1 to improve feelings of satiety and markers of blood glucose, and slow how fast the stomach empties. Lilly's drug also loops in a second gut hormone called GIP.
Tirzepatide sells as Mounjaro in diabetes treatment and as Zepbound as a weight-loss drug. Novo's drug sells as Ozempic and Wegovy, respectively.
Across all measures, tirzepatide came out ahead in the study. Patients taking tirzepatide were 2.6 times more likely to achieve at least 10% weight loss and 1.8 times more likely to hit at least 5% weight loss. The tirzepatide group also lost more weight at three, six and 12 months, Truveta said.
The results sent Novo Nordisk stock further below a buy point at 104 out of a flat base, according to MarketSmith.com. Shares initially broke out on Nov. 24, but toppled below their entry on Nov. 27. Eli Lilly stock is also forming a flat base with an entry at 629.97.
Follow Allison Gatlin on X, the platform formerly known as Twitter, at @IBD_AGatlin.
