Neurokinin-1-Receptor Antagonists: A New Approach in Antiemetic Therapy

Aprepitant (Emend), the first neurokinin-1-receptor antagonist (NK-1-RA), represents a new class of antiemetics. Aprepitant has been approved for the prevention and treatment of acute (0-24 h after chemotherapy) and delayed (1-5 days after chemotherapy) emesis resulting from cisplatin-based chemotherapy and moderately emetogenic chemotherapy. The addition of aprepitant to standard antiemetic therapy in cisplatin-based chemotherapy significantly improves emesis protection in general and, in particular, in the delayed phase by approximately 20%. Results from a recently published study in patients receiving moderately emetogenic chemotherapy suggest a benefit of aprepitant when combined with dexamethasone and a 5-HT(3) receptor antagonist for the prevention of acute emesis, followed by aprepitant as a single agent in the prevention of delayed emesis. Altogether, the addition of aprepitant to the standard antiemetic regimen (5-HT(3) receptor antagonist and dexamethasone) significantly improves the protection against vomiting in the acute as well as in the delayed phase in highly and moderately emetogenic chemotherapies. Therefore, the combination of a 5-HT(3) receptor antagonist, dexamethasone and aprepitant should be considered as a new standard antiemetic therapy.