Improved therapeutic performance of dithranol against psoriasis employing systematically optimized nanoemulsomes

Despite marked antipsoriatic activity of dithranol (anthralin), the drug is quite infrequently employed in therapeutic practice owing to its strong propensity to cause skin problems like irritation, erythema and peeling, and potential formulation problems like photolability and high lipophilicity. Accordingly, it was planned to systematically formulate optimized dithranol-loaded emulsomes with enhanced biocompatibility, efficacy and stability. Emulsomes were prepared by a thin film hydration technique and optimized for composition using formulation by design (FbD). The optimized dithranol-loaded emulsomes were found to substantially enhance the antipsoriatic activity on a mouse-tail model vis-à-vis marketed product. Also, the selected composition offered enhanced drug permeation and marked skin retention. The formulation was found to be quite non-irritant, stable and biocompatible in comparison to the marketed product. The present findings establish the usefulness of lipid-based colloidal carriers to increase the stability, and enhance the efficacy and patient compliance of an age-old irritant dithranol.