CAMBRIDGE, Mass. — Enveric Biosciences said a post-grant review petition challenging one of its U.S. patents has been withdrawn, leaving no remaining challenges pending against the patent.
The biotechnology company said the petition, filed by Gilgamesh Pharmaceuticals against Enveric’s U.S. Patent No. 12,138,276, was withdrawn following Enveric’s request for discretionary denial. The decision effectively ends the proceeding before the U.S. Patent and Trademark Office’s Patent Trial and Appeal Board.
The ’276 patent, titled “Halogenated psilocybin derivatives and methods of using,” includes claims that Enveric says are relevant to bretisilocin, a molecule currently in clinical trials.
Gilgamesh filed the post-grant review petition on August 12, 2025. Days later, on August 25, 2025, AbbVie agreed to acquire bretisilocin from Gilgamesh in a transaction valued at up to $1.2 billion. In a subsequent filing with the Patent Trial and Appeal Board, Gilgamesh disclosed that it had become a wholly owned subsidiary of an AbbVie-controlled entity and identified AbbVie as a real party-in-interest in the proceeding.
Enveric said it retained the intellectual property law firm Fish and Richardson P.C. in October 2025 to contest the petition. Later that month, the firm filed a request for discretionary denial on Enveric’s behalf. On November 20, counsel for AbbVie requested withdrawal of the petition, which the Patent Trial and Appeal Board has now granted.
“As a result of this action, there are no remaining challenges currently pending against Enveric’s patent,” the company said.
“Enveric is gratified by this turn of events, which we believe demonstrates our willingness to fully defend the intellectual property that protects our valuable discoveries,” said Joseph Tucker, Ph.D., Director and CEO of Enveric. “The fact that the PGR petition was filed in the first place underscored the breadth of our intellectual property footprint in the field, embodied by the numerous discoveries pertaining to next-generation, small-molecule psychedelics and potential non-hallucinatory neuroplastogenic therapeutics targeting psychiatric and neurological disorders.”
Tucker added that the company believes its patent portfolio will continue to generate value for shareholders and support efforts to develop new treatments for patients with mental health conditions.
