AbbVie has agreed to acquire Gilgamesh Pharmaceuticals' lead investigational drug, bretisilocin, a psychedelic compound in Phase II development for major depressive disorder. Bretisilocin is designed to provide therapeutic benefits with a shorter psychoactive experience compared to traditional psychedelics. Phase IIa trial results demonstrated a significant reduction in depression severity with good tolerability. The deal, valued at up to $1.2 billion, highlights AbbVie’s commitment to expanding its psychiatric portfolio and advancing innovative treatments for challenging mental health conditions.