REGENEXBIO, Penn University convince Federal Circuit Court to revive patent lawsuit against Sarepta

REGENEXBIO, Penn University convince Federal Circuit Court to revive patent lawsuit against Sarepta

The three-judge panel rejects the District Court’s ruling

Biotechnology company REGENEXBIO, Inc and the University of Pennsylvania have been able to convince the US Court of Appeals for the Federal Circuit to revive their patent lawsuit against Sarepta Therapeutics over Sarepta's Duchenne muscular dystrophy (DMD) treatment.

(DMD is a severe degenerative genetic disorder that primarily affects young boys. The U.S. Food and Drug Administration approved Sarepta's Elevidys, the first gene therapy for DMD, in 2023, and the drug earned Cambridge, Massachusetts-based Sarepta $898.7 million in revenue in 2025).

Thus, the Federal Circuit Court reinstated the case by reversing the ruling of Judge Richard Andrews of the District Court of Delaware. The judge had invalidated the patent related to REGENEXBIO’s competing gene-therapy technology.

Judge Andrews had dismissed the case after determining in 2024 that the patent was invalid because it covered naturally occurring DNA sequences.

However, a three-judge bench comprising Judge Kara Stoll, Judge Timothy Dyk and Judge Todd Hughes reversed the decision of the district court’s judge on observing that the patent covered genetically engineered cells with a molecule that was "markedly different from anything occurring in nature."

While Rockville, Maryland-based REGENEXBIO is developing its DMD treatment, its 2020 lawsuit said that Elevidys infringed a gene-therapy patent that REGENEXBIO licenses from Penn.

Both REGENEXBIO and the University of Pennsylvania have requested more than $900 million in damages in the matter.