Küleon LLC (formerly Psilosterics LLC) has announced a trifunctional serotonergic small molecule that is a full 5-HT2C receptor agonist and full antagonist of the 5-HT2A and 5-HT2B receptors with potential to treat neuropsychiatric disorders. Designated KB-128, it could be developed to treat disorders that can be modulated though 5-HT2C receptors, including schizophrenia, Alzheimer’s psychosis, depression, obesity and addiction.