Overview

• AbbVie signed a definitive agreement to acquire bretisilocin, an investigational therapy for moderate-to-severe major depressive disorder, in a deal comprising an upfront payment and development milestones.
• Bretisilocin is a next-generation 5-HT2A receptor agonist and 5-HT releaser engineered to shorten the psychoactive experience while preserving therapeutic benefit.
• In a Phase 2a trial, a single 10 mg dose reduced MADRS scores by 21.6 points at Day 14 versus 12.1 for a low-dose comparator (p=0.003), with no serious adverse events reported.
• Gilgamesh will spin off Gilgamesh Pharma Inc. to retain its employees and programs including blixeprodil (GM-1020), a cardio-safe ibogaine analog, and an M1/M4 agonist, and AbbVie’s prior option-to-license will transfer to the new entity.
• The transaction builds on the companies’ 2024 collaboration, remains subject to customary closing conditions, and is viewed by analysts as strengthening AbbVie’s neuroscience portfolio and signaling big-pharma interest in psychedelics.