Aprepitant isa potent and selective antagonist of human substance P/neurokinin 1 (NK1) receptors used clinically to treat chemotherapy-induced or post-operative nausea and vomiting, and being investigated for other activity including possible treatment for depression and pruritis.
Aprepitant: a neurokinin-1 receptor antagonist for the treatment of chemotherapy-induced nausea and vomiting. 
Cyclopentane-based human NK1 antagonists. Part 2: Development of potent, orally active, water-soluble derivatives. 
Identification of a crucial amino acid in the helix position 6.51 of human tachykinin neurokinin 1 and 3 receptors contributing to the insurmountable mode of antagonism by dual NK1/NK3 antagonists.