DRD1 and schizophrenia: Dysregulation of DRD1 signaling has been directly linked to Parkinson’s disease (PD), schizophrenia, and drug abuse.1,2 Due to its fundamental functions in human diseases, DRD1 has long been the subject of intensive drug development efforts toward the treatment of neuropsychiatric diseases.3 A majority of DRD1 agonists, including the SKF compounds, targets the orthosteric pocket of DRD1, but none has passed clinical trials for neuropsychiatric symptoms to date.3