By Jonathan Stempel
NEW YORK, Feb 23 (Reuters) - Bayer sued Johnson & Johnson on Monday, accusing the drugmaker of falsely advertising a rival multibillion-dollar drug to treat prostate cancer.
In a complaint filed in Manhattan federal court, Bayer said Johnson & Johnson is causing irreparable harm through a campaign begun this month for the drug Erleada that threatens to erode trust in the German company's drug Nubeqa.
Bayer said Johnson & Johnson falsely claimed that patients treated with Erleada
had a "51% reduction in risk of death" compared with Nubeqa patients, in testing that replicated a clinical trial and adhered to "rigorous" U.S. Food and Drug Administration standards.
According to the complaint, the two groups of patients were not comparable because most Nubeqa patients in the comparison received their drug off-label, creating "selection bias" that makes claims of superiority unreliable, and Johnson & Johnson's study included five times more patients.
Bayer also said the FDA does not sanction the retrospective, real-world analysis that Johnson & Johnson allegedly used as a substitute for traditional clinical trials.
"By invoking FDA authority to lend unwarranted credibility to scientifically flawed analyses, J&J has misled patients and healthcare providers," the complaint said.
Johnson & Johnson, based in New Brunswick, New Jersey, did not immediately respond to requests for comment.
BAYER SAYS AI SPREADS JOHNSON & JOHNSON'S FALSE MESSAGE
Bayer is seeking punitive and triple damages, the recoupment of ill-gotten profit, and an injunction against further false advertising.
The complaint also said artificial intelligence - reflected in a Google search regarding Erleada, Nubeqa and risk of death - is amplifying Johnson & Johnson's false claims, and feeding people "unsubstantiated messages about the risk of dying with Nubeqa."
About 313,780 men were diagnosed with prostate cancer in the United States in 2025, and 35,770 died from the disease that year, according to the National Cancer Institute.
Nubeqa sales totaled about 1.63 billion euros ($1.92 billion) in the first nine months of 2025, while Erleada sales totaled $2.62 billion over approximately the same period. Full-year sales of Erleada totaled $3.57 billion.
(Reporting by Jonathan Stempel in New York; Additional reporting by Friederike Heine in Berlin; Editing by Tomasz Janowski, Chizu Nomiyama and Matthew Lewis)
