AbbVie Withdraws Patent Challenge Against Enveric, Signaling Confidence in Bretisilocin
Event summary
- Enveric Biosciences’ patent (US 12,138,276) covering halogenated psilocybin derivatives, relevant to its bretisilocin (GM-2505) drug candidate, was the subject of a Post-Grant Review (PGR) petition filed by Gilgamesh Pharmaceuticals.
- AbbVie acquired Gilgamesh Pharmaceuticals and its bretisilocin asset for up to $1.2 billion on August 12, 2025, making Gilgamesh a wholly-owned subsidiary of AbbVie.
- Enveric retained Fish and Richardson P.C. to contest the PGR petition, filing a Request for Discretionary Denial.
- AbbVie, through its subsidiary, formally requested the withdrawal of the PGR petition, which the USPTO granted on November 20, 2025.
- The withdrawal effectively ends all current challenges to Enveric’s patent.
The big picture
The withdrawal of the patent challenge by AbbVie, now the owner of Gilgamesh, highlights the increasing scrutiny and legal battles surrounding intellectual property in the psychedelic-assisted therapy and neuroplasticity space. The $1.2 billion acquisition price for bretisilocin underscores the significant commercial potential of these therapies, but also the intense competition to secure patent protection. This event suggests AbbVie sees value in the underlying technology, even if it initially questioned the patent’s validity.
What we're watching
- Deal Implications
- AbbVie’s decision to withdraw the patent challenge suggests a level of comfort with Enveric’s intellectual property, but the underlying rationale for the initial challenge warrants further investigation – was it a strategic delaying tactic or a genuine concern about patent validity?
- Clinical Progress
- The success of bretisilocin’s clinical trials remains paramount; any setbacks could undermine the value of the acquired asset and potentially re-open questions about the patent’s strength.
- Patent Landscape
- While this challenge is resolved, Enveric's broader patent portfolio and its ability to defend it against future challenges will be critical to maintaining a competitive advantage in the emerging neuroplastogenic therapeutics space.
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