Palonosetron (RS25259, RS 25259 197) is a 5-HT3 antagonist with Ki value of 0.17 nM. It is used in the prevention and treatment of chemotherapy-induced nausea and vomiting (CINV).
Palonosetron is a 5-HT3 receptor antagonist with a high binding affinity for this receptor and little or no affinity for other receptors[1].
Palonosetron has a longer half-life and a higher binding affinity than the first-generation 5-HT3 receptor antagonists. After intravenous dosing of palonosetron in healthy subjects and cancer patients, an initial decline in plasma concentration is followed by a slow elimination from the body. Mean maximum plasma concentration and area under the concentration-time curves are generally dose-proportional over the dose range of 0.3 to 90 μg/kg in healthy subjects and in cancer patients. Palonosetron has a volume of distribution of approximately 8.3 ± 2.5 L/kg and is 62% bound to plasma proteins. It is eliminated from the body through renal excretion and metabolic pathways. The mean terminal elimination half-life is approximately 40 hours[1].
[1] Rudolph M Navari. Cancer Manag Res. 2009, 1: 167-176. [2] Price KL, et al. ACS Chem Neurosci. 2016, 7(12):1641-1646.