Acadia Pharmaceuticals is a biopharmaceutical company focused on the development and commercialization of medicines that address unmet medical needs in central nervous system disorders. Co. has a portfolio of product including its drug, NUPLAZID (pimavanserin), which has been approved by the U.S. Food and Drug Administration for the treatment of hallucinations and delusions associated with Parkinson's disease psychosis. NUPLAZID is a selective serotonin inverse agonist/antagonist, targeting 5-HT2A receptors with no appreciable affinity for dopaminergic, histaminergic, or muscarinic receptors.