Eisai wins favorable US patent infringement ruling related to lenvatinib

Japanese drugmaker Eisai (TYO: 4523) said yesterday that it has received a favorable decision regarding the lawsuit filed in the US District Court for the District of New Jersey in November 2019 against generic drug manufacturer Shilpa Medicare, which submitted an Abbreviated New Drug Application (ANDA) for a generic version of Lenvima (lenvatinib), for infringement of US Patent No 11,186,547.

In November 2019, Eisai and US pharma giant Merck & Co (NYSE: MRK) brought an infringement action against Shilpa Medicare after Shilpa filed for approval of a generic version of the companies' drug.

The case has been closely watched throughout the pharmaceutical industry as one of the first patent litigations in the context of the Hatch-Waxman Act to assess the validity of patent claims directed to highly pure forms of an active ingredient. The case will be an influential precedent for other innovator companies with pending purity patent challenges.