Pharmacological Characterization of the Imipridone Anticancer Drug ONC201 Reveals a Negative Allosteric Mechanism of Action at the D Dopamine Receptor.

ONC201 is a first-in-class imipridone compound that is in clinical trials for the treatment of high-grade gliomas and other advanced cancers. Recent studies identified that ONC201 antagonizes D2-like dopamine receptors at therapeutically relevant concentrations. In the current study, characterization of ONC201 using radioligand binding and multiple functional assays revealed that it was a full antagonist of the D2 and D3 receptors (D2R and D3R) with low micromolar potencies, similar to its potency for antiproliferative effects.

Dopamine D Receptor-Selective Compounds Reveal Structure-Activity Relationships that Engender Agonist Efficacy.

The dopamine D receptor (DR) plays important roles in cognition, attention, and decision making. Novel DR-selective ligands have promise in medication development for neuropsychiatric conditions, including Alzheimer's disease and substance use disorders. To identify new DR-selective ligands, and to understand the molecular determinants of agonist efficacy at DR, we report a series of eighteen novel ligands based on the classical DR agonist A-412997 (1, 2-(4-(pyridin-2-yl)piperidin-1-yl)- N-( m-tolyl)acetamide).