SB269652 is an experimental dopamine D<sub>2</sub> and D<sub>3</sub> receptor negative allosteric modulator. It is of interest in the potential development of novel antipsychotics for treatment of schizophrenia with reduced side effects, such as extrapyramidal symptoms. The drug is described as a dual and allosteric (i.e., bitopic) modulator of the dopamine D<sub>2</sub> and D<sub>3</sub> receptors, as an atypical allosteric modulator of these receptors, and as specifically targeting D<sub>2</sub>âÂÂD<sub>3</sub> receptor dimers. SB269652 was first described in the scientific literature by 1999. It was originally thought to act purely as an antagonist of the dopamine D<sub>2</sub> and D<sub>3</sub> receptors, but was serendipitously found to be a negative allosteric modulator of these receptors in 2010. It was the first dopamine D<sub>2</sub> and D<sub>3</sub> receptor negative allosteric modulator to be discovered. More potent analogues of SB269652 have been developed.