Sarepta Exes Out RegenxBio Patent in Delaware Federal Lawsuit

A federal judge in Delaware wiped out parts of a RegenxBio Inc. patent covering a treatment for Duchenne muscular dystrophy—a fatal blow for the company’s lawsuit against Sarepta Therapeutics Inc.

RegenxBio and the University of Pennsylvania sued Sarepta in September 2020 for infringement of the since-expired US Patent No. 10,526,617 based on Sarepta’s manufacturing of a gene therapy product used to treat the disease. RegenxBio estimated during a May 2023 discovery conference that, if it could prove infringement, it would seek “just a little over $900 million” in damages.

Judge Richard G. Andrews of the US District Court for the ...