Intradermal delivery of teriflunomide loaded emulsomes using hollow microneedles for effective minimally invasive psoriasis management

Abstract

Conventional topical psoriasis treatments suffer from limited delivery to affected areas along with skin irritation due to high local drug concentration. Herein an attempt to improve the delivery of leflunomide’s active metabolite (teriflunomide (TER)) by improving its solubility through nanoencapsulation in emulsomes (EMLs) besides ensuring effective intradermal delivery using hollow microneedles. Evaluation of colloidal characteristics of EMLs, encapsulation efficiency and drug release were performed. Additionally, the antipsoriatic activity in an imiquimod-induced psoriatic mouse model was evaluated by the measurement of inflammatory mediators’ levels and histopathological assessment of anatomized skin. The particle size of the chosen EMLs formulation was 147.9 nm and the zeta potential value was −21.7. Entrapment efficiency was 97.23 % and EMLs provided sustained drug release for 48 h. No statistically significant differences in the in vivo levels of NF-KB, IL 8, MMP1, GSH, SOD and catalase between the animals treated by TER-EMLs and the negative control cohort were observed. Also, histopathological inspection of dissected skin samples reflected the superiority of TER-EMLs over TER suspension. Collectively, combining nanoencapsulation and hollow microneedles application improved TER properties and ensured effective TER delivery to the affected psoriatic areas.