Palonosetron HCl Injection is an antiemetic and antinauseant agent. It is a serotonin-3 (5-HT3) receptor antagonist with a strong binding affinity for this receptor. Chemically, palonosetron hydrochloride is: (3aS)-2-[(S)-1-Azabicyclo [2.2.2]oct-3-yl]-2,3,3a,4,5,6-hexahydro-1-oxo-1Hbenz[de]isoquinoline hydrochloride. The empirical formula is C19H24N2O.HCl, with a molecular weight of 332.87. Palonosetron hydrochloride exists as a single isomer and has the following structural formula:
Palonosetron hydrochloride is a white to off-white crystalline powder. It is freely soluble in water, soluble in propylene glycol, and slightly soluble in ethanol and 2-propanol.
Palonosetron HCl Injection is a sterile, clear, colorless, non-pyrogenic, isotonic, buffered solution for intravenous administration. Palonosetron HCl Injection is available as a 5 mL or 1.5 mL single-dose vial.
Each 5 mL vial contains: 0.25 mg palonosetron (equivalent to 0.28 mg palonosetron HCl), 207.5 mg mannitol, disodium edetate and citrate buffer in water for intravenous administration.
Each 1.5 mL vial contains: 0.075 mg palonosetron (equivalent to 0.084 mg palonosetron HCl), 62.25 mg mannitol, disodium edetate and citrate buffer in water for intravenous administration.
The pH of the solution in the 5 mL and 1.5 mL vials is 4.5 to 5.5.