WAY-388798 is primarily used in scientific research as a potent and selective agonist for the GPR139 receptor, a G-protein-coupled receptor expressed in the brain. Its main application lies in neuropharmacological studies, where it helps investigate the role of GPR139 in modulating neurotransmitter systems, particularly those involving dopamine and glutamate. Researchers use WAY-388798 to explore potential links between GPR139 activation and conditions such as schizophrenia, depression, and addiction. Due to its high selectivity, it serves as a valuable tool compound for validating GPR139 as a therapeutic target and for understanding downstream signaling pathways in neuronal circuits. It is not used clinically and remains restricted to preclinical research settings.