(Bloomberg) -- Bayer AG and Johnson & Johnson won a trial court ruling that upheld the validity of a patent on the blood-thinning drug Xarelto.

Mylan NV and Sigmapharm Laboratories failed to prove the patent shouldn’t have been issued, District Court Judge Lawrence Stengel said in a ruling posted on the court’s docket. The generic-drug companies, who are looking to sell low-cost versions of the drug, had conceded they infringed the patent, which expires in August 2024.

To contact the reporter on this story: Susan Decker in Washington at sdecker1@bloomberg.net

To contact the editors responsible for this story: Jon Morgan at jmorgan97@bloomberg.net, Laurie Asséo

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