Non-invasive endotracheal delivery of paclitaxel-loaded alginate microparticles

Aerosolized chemotherapeutics leads to higher, localized and continuous concentrations of active agents in lung tissue with lower side effects for other organs. The present study was performed on jugular vein cannulated rats which endothracheally received 4 mg/kg of free paclitaxel powder (Free-PTX), paclitaxel-loaded alginate microparticles (PTX-ALG-MPs) and i.v. paclitaxel (Anzatax^®). Pharmacokinetic parameters for Free-PTX and PTX-ALG-MPs contain higher AUC, mean residence time (MRT),half-life and bioavailability, with lower elimination constant (k_e). Statistical analysis showed that the amount of paclitaxel per gram of lung tissue after 0.5, 6 and 24 h after administration of Free-PTX was lower than PTX-ALG-MPs. Lung tissue AUC for Free-PTX was lower than PTX-ALG-MPs. According to the obvious advantages obtained, such as dose lowering and increasing paclitaxel residence time and half-life. It should be noted that cell cytotoxicity test on normal airway cell lines was not examined in this study but due to previous reports on safety of inhaled paclitaxel, it can be suggested that pulmonary delivery of paclitaxel can be a useful non-invasive route of administration compared with i.v administration.