Development of Novel Polymer-Lipid Hybrid Nanoparticles of Tamoxifen: In Vitro and In Vivo Evaluation

This study was undertaken to develop and investigate the effect of tamoxifen polymer-lipid hybrid nanoparticles (Tmx-PLN) on its oral bioavailability and efficacy in the 7,12-dimethylbenzanthracene (DMBA)-induced breast cancer model. Modified solvent emulsification-evaporation method was optimized to obtain Tmx-PLN, composed of chitosan and lecithin, of 169.66 +/- 4.84 nm particle size. The PLN exhibited prolonged in vitro release in phosphate-buffered saline. Further, PLN displayed enhanced oral bioavailability with considerable increase in AUC (1277.46 vs. 585.01 ng/ml . h), prolonged t(1/2) (27.87 +/- 15.62 vs. 10.18 +/- 6.5 h) and mean residence time (40.11 +/- 25.72 vs. 17.42 +/- 12.04 h) in comparison to pure Tmx. In addition, PLN exhibited significantly increased (P < 0.05) antitumor efficacy in DMBA-induced breast cancer model, when administered once in three days in comparison to Tmx daily dosing. This enhancement may be attributed to a probable reduction in Pgp efflux, decreased first-pass metabolism and lymphatic drug transport. Thus, Tmx-PLN exhibited enhanced potential to increase Tmx therapeutic efficacy in chronic treatment of breast cancer.