Palonosetron is a highly selective, high-affinity 5-HT3 receptor antagonist. Due to its structural difference from the first-generation 5-HT3 receptor antagonists, palonosetron has an affinity for the 5-HT3 receptor at least 30 times that of other similar drugs.
Palonosetron is neither an inhibitor of CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2D6, CYP2E1 and CYP3A4/5 (CYP2C19 not studied) nor does it induce the activity of CYP1A2, CYP2D6 or CYP3A4/5.
