Nanoencapsulation of Fenretinide in Glucosamine Butyrate - GelatinMatrices as a Mean to Improve its Oral Bioavailability

Fenretinide (4-HPR) is the most promising retinoid derivative with anticancer activity and low toxicity profile. Despite its excellent tolerability, the formulations of 4-HPR that have been clinically evaluated until now have not provided drug plasma concentrations suitable to elicit a therapeutic response. Therefore innovative formulations able to improve the drug bioavailability would be of considerable interest. In this work we describe the preparation and functional evaluation of novel nanocapsules designed to enhance fenretinide bioavailability by oral route through the use of glucosamine butyrate as bioavailability enhancer and gelatin as a matrix forming agent. The anti-tumour activity of the nanocapsules has been tested in in vitro and in vivo models either in feeding and fasting conditions. Our data indicated that after oral administration the nanocapsules provide 4-HPR plasma concentrations in the range compatible with the antitumor activity as assessed in vitro expecially in fasting conditions. Moreover these novel nanocapsules have proved to be effective in tumor xenografts after oral administration.