Preparation and pharmacokinetics of pirarubicin loaded dehydration-rehydration vesicles

Liposomes entrapped pirarubicin (THP, L-THP) were prepared by the modified dehydration-rehydration vesicle (DRV) method, and their pharmacokinetics and antitumor effects were evaluated in mice bearing M5076 liver metastasis tumor. After small unilamellar vesicles (SUVs) composed of egg lecithin, cholesterol (Ch), beta-sitosterol beta-D-glucoside (Sit-G) and oleic acid (OA) were freeze-dried with THP and sugars, rehydration of the lyophilized powders led to form the larger vesicles entrapping drugs, but the proper amounts of sugars and OA to lipids (sucrose/lipid=8 (w/w)) maintained the small particle size (about 340nm) with high entrapment (80.7%) of THP. After intravenous injection of L-THP, the accumulations of THP in the liver and heart were approximately 4-fold higher and half lower, respectively, than those of free THP (F-THP). L-THP had superior antitumor effect in 10mg/kg intravenous administration without significant body weight loss. L-THP is a potential drug dosage form of liver cancer treatment since the liposomes carry THP to the liver.