Development and Evaluation of Azelaic Acid Based Ethosomes for Topical Delivery for the Treatment of Acne

Purpose: To design, develop and evaluate an Azelaic acid encapsulated Ethosomal formulation for acne. Methods: Encapsulated ethosomes were prepared by three methods viz. hot method, cold method and thin film hydration method. Central Composite Design was employed for optimisation of ethosomal formulations. Concentrations of phospholipid, cholesterol and ethanol were selected as independent variables and their effect on the dependent variables (Entrapment Efficiency and Drug Diffused) was studied. The optimised vesicular carriers were evaluated for vesicle size, entrapment efficiency, in-vitro and ex-vivo diffusion studies, anti-microbial activity, skin irritation studies and stability studies as per ICH guidelines. Ethosomal formulations with varying soya phosphatidylcholine, cholesterol and ethanol were prepared. Results: Vesicles were spherical, unilamellar with a smooth surface. The optimised formulation showed a vesicle size of 4.25 +/- 1.35 mu m and entrapment efficiency of 91.86 +/- 2.25%. In-vitro and ex-vivo drug diffusion of the ethosomal gel was compared with a conventional gel and a marketed cream. The developed novel formulation exhibited enhanced anti-acne activity as compared to conventional gel and a marketed cream. Conclusion: We can conclude that the ethosomal formulation is an efficient vesicular carrier system for topical delivery.