Topical Liposomal Gel of Tretinoin for the Treatment of Acne: Research and Clinical Implications

Abstract

An attempt was made to pharmaceutically develop a topical liposomal tretinoin (TRE) gel and clinically evaluate the developed formulation for the treatment of acne in patients. Liposomes of TRE were prepared using the lipid film hydration technique and the entrapment efficiency of TRE in liposomes was optimized to 79.96%. The drug retention in liposomes and in liposomal TRE gel (Carbopol 934 gel base) studied at three storage conditions indicated maximum drug retention at refrigeration temperature. For liposomal TRE gel, reduced drug leakage was observed as compared to that of liposomes at all three storage conditions. Diffusion studies of plain TRE gel and liposomal TRE gel suggested prolongation (3.4 times reduction in flux value) of drug diffusion and almost two- fold increase in skin drug retention after liposomal encapsulation of drug. A comparative double-blind clinical study of the developed liposomal TRE gel, carried out on 30 acne patients over a period of 3 months, demonstrated significant enhancement (about 1.5-fold) in drug efficacy. More remarkable improvement was observed in the treatment of comedones, where the mean percent reduction in lesions increased from 62.36% for plain TRE gel to 94.17% for liposomal TRE gel. Erythema and irritation associated with the use of plain TRE gel was reduced considerably with the use of liposomal TRE gel. The findings of this investigation therefore underscore potential utility of commercialization of liposomal TRE gel in the treatment of acne.