Used as a potent and selective antagonist for the neurokinin-1 (NK1) receptor, this compound is primarily applied in neuroscience research to study the role of substance P in pain transmission, inflammation, and emotional behavior. It helps in investigating potential treatments for conditions such as depression, anxiety, and nausea, especially in preclinical models. Due to its high affinity for the NK1 receptor, it is also utilized in receptor binding assays and pharmacokinetic studies to evaluate central nervous system penetration and target engagement.