WAY-299819 is a selective agonist for the GPR139 receptor, a G-protein-coupled receptor expressed primarily in the brain, particularly in regions associated with motor control and reward processing. Its primary application lies in neuroscience research, where it is used to probe the functional role of GPR139 in behavioral and neurochemical pathways. Studies have utilized WAY-299819 to investigate its potential involvement in modulating dopamine and glutamate transmission, suggesting relevance in understanding disorders such as schizophrenia, depression, and Parkinson’s disease. Due to its ability to cross the blood-brain barrier, it is valuable in in vivo models for assessing central nervous system effects. Currently, it remains a research tool and is not used clinically, but it supports the development of future therapeutics targeting GPR139-related pathways.