Preparation and Evaluation of Liposomal Flucinolone Acetonide Gel for Intradermal Delivery

Hydroxypropyl methylcellulose (HPMC) K4M gels containing free flucinolone acetonide, liposomal-encapsulated flucinolone acetonide and physical mixture of the drug and lipids were prepared and evaluated in in-vitro drug release studies using rat skin to determine diffusion parameters. Data were analysed to calculate the quantity of the drug remaining in the skin (Qm) and in the blood (Csf) and the ratio of Qm to Csf. The in-vivo skin blanching assay performed with these formulations in human volunteers showed low blanching scores for liposomal gel formulations indicating low absorption of the liposomal-encapsulated drug into the blood stream and leading to the accumulation of the drug in the skin. This result is in agreement with the high Qm/Csf ratios obtained in the in-vitro experiments. Of all the formulations, gels containing liposomal-encapsulated flucinolone acetonide, prepared with drug, phosphatidyl choline and cholesterol in the ratio of 4:8:1, had the highest Qm/Csf ratio and minimum blanching score. The results indicate the potential of topical preparations containing liposomal-encapsulated drugs for selective accumulation of the drug in the skin.