NEW YORK – A federal district court judge on Friday ruled that certain claims in a patent related to a Duchenne muscular dystrophy (DMD) gene therapy being developed by Regenxbio are invalid.
The decision quashes a patent infringement lawsuit that Regenxbio and the trustees of the University of Pennsylvania filed against Sarepta Therapeutics in September 2020 in a Delaware federal court. The plaintiffs alleged that Sarepta was illegally using their patented cultured host cell technology without a license to develop products such as Elevidys (delandistrogene moxeparvovec-rokl). Sarepta garnered accelerated approval from the US Food and Drug Administration last year for Elevidys, making it the first gene therapy for DMD to reach the market.
Elevidys uses an adeno-associated virus (AAV) vector to deliver a copy of a gene that encodes for microdystrophin, an engineered protein Sarepta developed and which the company said can carry out the normal functions of the protein lacking in DMD patients, dystrophin.
The plaintiffs in the lawsuit accused Cambridge, Massachusetts-based Sarepta of infringing US Patent No. 10,526,617, granted to UPenn in January 2020, which outlines methods for identifying and isolating novel AAV sequences. UPenn granted Rockville, Maryland-based Regenxbio an exclusive worldwide license to that patent to use in its own gene therapy development efforts. For example, Regenxbio is developing an AAV-based gene therapy for DMD, dubbed RGX-202, which is currently in a Phase I/II trial.
However, in an opinion Friday, Judge Richard Andrews for the US District Court for the District of Delaware ruled that parts of the patent the plaintiffs accused Sarepta of infringing are invalid, since the AAV vector sequences in question are naturally occurring. The US Supreme Court in 2013 ruled in Association for Molecular Pathology v. Myriad Genetics that subject matter based on "laws of nature" are not patent eligible.
"Plaintiffs do not suggest that the isolated rh.10 sequences are any different from those found in nature, and isolation on its own is insufficient to create patent-eligible subject matter," Andrews wrote. "I agree with defendants that the claims lack an inventive concept that could transform the claimed invention into patent-eligible subject matter."
A decision on a separate patent infringement claim against Sarepta based on US Patent No. 11,680,274, also granted to UPenn and licensed to Regenxbio, is pending. That patent claim describes a method of increasing the function of an AAV vector, which Regenxbio and UPenn allege Sarepta has illegally used to commercially launch products such as Elevidys.
A Sarepta spokesperson in an email said the company was pleased with Andrews' decision, characterizing it as a "win for patients and for innovation."
Regenxbio Chief Legal Officer Patrick Christmas in an email stated that the firm is "disappointed" by the decision and intends to appeal it in collaboration with UPenn. He stressed that the ruling does not impact the company's therapeutic pipeline or other licenses, since the patent expired in 2022.
In a separate public statement, Regenxbio President and CEO Kenneth Mills said, "We are not attempting to halt development or production of gene therapies; we are seeking fair and reasonable compensation for deliberate infringement."
A spokesperson for UPenn said that the university does not comment on litigation.
When Sarepta received accelerated approval from the FDA last year for Elevidys, the agency limited the indication to patients between 4 and 5 years old. Sarepta is currently working on expanding the indication to encompass all ages and convert the accelerated approval to a traditional approval.