Enhanced absorption and tissue distribution of paclitaxel following oral administration of DHP 107, a novel mucoadhesive lipid dosage form

Purpose: This study was conducted to examine the absorption and tissue distribution characteristics of paclitaxel-loaded DHP 107, a Cremophor EL-free, mucoadhesive lipid oral dosage form. Methods: DHP 107 was orally administered to mice at 10, 20 and 40 mg/kg doses. For comparison purposes, Taxol was i.v. injected at 5, 10 and 20 mg/kg doses. Drug levels were determined in plasma and tissues by validated HPLC assays. The absolute bioavailability and the relative distribution to various tissues were calculated as a function of dose. Results: The dose-normalized plasma AUC_{DHP 107}/AUC_Taxol ratios calculated at comparable AUC values ranged from 14.6 to 29.0%. In contrast, relative tissue distribution ratios calculated as the dose-normalized AUC _{DHP 107}/AUC_Taxol were as high as 342.0, 139.0, 112.9 and 108.2% for stomach, small intestine, large intestine and ovary, respectively. Conclusions: Oral administration of DHP 107 provided a substantial systemic absorption of paclitaxel. Furthermore, the relative distribution ratios of DHP 107 at doses of 20 and 40 mg/kg were higher for stomach, small intestine, large intestine, and ovary than the systemic bioavailability, providing a basis for therapeutic advantages.