The pharmacokinetic comparison of paclitaxel injection and paclitaxel liposome in rats

Objective To compare the differences of pharmacokinetic parameters of paclitaxel injections and liposome.Methods An high performance liquid chromatography (HPLC) assay method was established to estimate the blood concentrations of paclitaxel after caudal vein administration of 12 mg/kg weigh.The blood concentration-time curves as well as correlated pharmaciokinetic parameters were obtained.Moreover,the data were analyzed with t-test.Results In rats,the mean drug concentration in plasma of paclitaxel injection and paclitaxel liposome were (0.18 ± 0.07)C/(mg · L) and (50 ± 9.2)C/(mg · L),respectively,and there were significant differences between the two formulations (t =5.879,P ＜ 0.01) ;compared with paclitaxel injection,the area under concentration-time curve (AUC) was bigger (17.693 ±2.657 vs 10.812 ± 2.846,t =4.892,P ＜ 0.01),the apparent volume of distribution (Vc) was smaller [(1.629 ±4.91) × 10-3 L vs (5.268 ± 1.121) × 10-3 L,t =3.75,P ＜0.01],the clearance rate(Cl)was slower[(7.2 ± 1.0) × 10-4 L vs (1.2 ±2.7) × 10-4 L,t =4.25,P ＜ 0.01],in the paclitaxel liposome.Conclusions Paclitaxel liposome has higher efficacy,longer release time,higher target tissue concentration,and lower side effects than paclitaxel injection. Key words: Liposomes/pharmacokinetics ;  Paclitaxel/pharmacokinetics ;  INJECTIO ;  Chromatography, high pressure liquid