Optimization and Characterization of a Tofacitinib Citrate-Loaded Dermal Nanoemulgel for Rheumatoid Arthritis

Abstract

Aim: Rheumatoid Arthritis (RA) is a progressive autoimmune disorder characterized by joint inflammation and functional disability. Conventional oral therapy with tofacitinib citrate exhibits poor bioavailability as it undergoes extensive hepatic metabolism, and is associated with systemic adverse effects. The present research proposes a novel topical nanoemulgel formulation of tofacitinib to overcome the drawbacks of conventional therapy. Materials and Methods: Nanoemulsion was prepared with eucalyptus oil, tween 20, and labrafil M2125. A statistical design was employed to optimize drug loading and particle size. The optimized nanoemulsion was incorporated into a Carbopol 934 gel base and evaluated for physicochemical properties, rheology, spreadability, ex vivo permeation, and in vivo antiarthritic activity. Results: The optimized nanoemulsion exhibited a mean particle size of 180 nm, drug loading of ~71%. Surface morphology by TEM confirmed formation of stable nanosized vesicles. The nanoemulgel exhibited favourable viscosity, pH, spreadability, and sustained release profile. Ex vivo studies confirmed enhanced permeation compared to pure drug gel. In vivo results demonstrated reduced paw edema, improved mobility, and near-normal histological architecture. Conclusion: Therefore, nanoemulagel of tofacitinib citrate can be a promising alternative to oral therapy in RA management.