WAY-119918 is primarily used in scientific research as a selective antagonist for the neurokinin-3 (NK3) receptor. It has been employed to study the role of tachykinin signaling in the central nervous system, particularly in relation to psychiatric and neurological disorders. Researchers utilize this compound to investigate potential pathways involved in schizophrenia, mood disorders, and cognitive dysfunction due to its ability to modulate neurotransmitter systems such as dopamine. Its application is limited to preclinical studies, aiding in the development of novel therapeutics targeting NK3 receptor activity.