Nuplazid, a drug developed by Acadia in the late 1990s, "was designed to stimulate a subset of the brain’s serotonin receptors, or the proteins that govern memory, cognition and learning." On April 29, 2016, the
FDA approved Acadia's drug, Nuplazid, for the treatment of hallucinations and delusions associated with
Parkinson's disease psychosis. Nuplazid is the trade name for Acadia's proprietary molecule,
pimavanserin, a selective serotonin inverse agonist preferentially targeting 5-HT2a receptors. Acadia had partnered with
Biovail in the late-stage clinical testing of the drug, which showed trial failures as of 2009. Acadia is running multiple Phase 2 and Phase 3 trials with pimavanserin in several central nervous system conditions:
dementia-related psychosis,
major depressive disorder,
schizophrenia inadequate response, and schizophrenia negative symptoms. , Acadia was among several companies that licensed compounds from
Genzyme's small-molecule
compound library. In 2023, the FDA approved
trofinetide (marketed as Daybue) for use in Rett syndrome. == History ==