Key Highlights
- AbbVie acquires Gilgamesh’s lead candidate bretisilocin (GM-2505), a short-acting psychedelic in Phase 2 for major depressive disorder, in a deal worth up to $1.2B.
- Early clinical data show a single 10mg dose delivered a -21.6 MADRS score change at Day 14, demonstrating rapid and durable antidepressant benefits with fewer safety concerns.
- Acquisition strengthens AbbVie’s late-stage neuroscience pipeline, positioning it as a leader in next-generation psychiatric therapies.
The Promise of Bretisilocin
Bretisilocin (GM-2505) is a novel, short-acting 5-HT2A receptor agonist and 5-HT releaser designed to overcome challenges seen with earlier psychedelic agents, notably long psychoactive durations that limit clinical use. In a recent Phase 2a study, bretisilocin delivered statistically significant and clinically meaningful reductions in depressive symptoms, with rapid onset and durability, while maintaining a favorable safety profile.
AbbVie’s Strategic Expansion in Psychiatry
The acquisition underlines AbbVie’s commitment to addressing unmet needs in psychiatry, one of the most challenging areas in medicine. With bretisilocin, AbbVie aims to expand its neuroscience portfolio beyond symptom management, toward transformative therapies with the potential to impact millions of patients resistant to existing antidepressants.
Gilgamesh’s Next Chapter
As part of the transaction, Gilgamesh will spin out a new entity, Gilgamesh Pharma Inc., which will retain its broader pipeline—including oral NMDA receptor antagonist blixeprodil, cardio-safe ibogaine analogs, and an M1/M4 agonist program. This structure ensures both companies can advance parallel missions: AbbVie accelerating late-stage development of bretisilocin, and Gilgamesh Pharma driving earlier-stage innovation.
A Pivotal Deal for the Future of Mental Health
Valued at up to $1.2 billion, inclusive of upfront and milestone payments, this transaction marks one of the most significant moves in the emerging psychedelic medicines market. It signals growing biopharma confidence in next-generation psychiatric treatments and highlights how large pharma is embracing novel approaches to mental health at scale.
About AbbVie
AbbVie is a global biopharmaceutical company committed to discovering and delivering innovative medicines in areas such as immunology, oncology, neuroscience, eye care, and specialty therapies. Its diverse portfolio addresses some of the world’s most serious health challenges, with a focus on advancing science and improving patient outcomes worldwide.
About Gilgamesh Pharmaceuticals
Gilgamesh Pharmaceuticals is a clinical-stage biotechnology company focused on developing next-generation neuropsychiatric therapeutics. The company leverages novel psychedelic-inspired compounds and rational drug design to create safer, more effective treatments for mental health disorders with high unmet need.
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