Tofacitinib citrate-based liposomes for effective treatment of rheumatoid arthritis.

Low drug concentrations at interest sites and unwanted systemic side effects are major obstacles to effective therapy of rheumatoid arthritis (RA). With the aim of improving the efficacy of tofacitinib citrate (TOF), a liposomal system was developed for targeted delivery to inflamed joints, and this approach was validated in a RA rat model. TOF was effectively loaded into the liposomes (entrapment efficiency: 86.5±1.9%; drug loading: 2.3±0.05%) by a pH gradient method, and these molecules featured sustained drug release behaviour over 48 h. In vitro and in vivo studies showed that TOF loaded liposomes (TOFL) could be selectively taken up by inflamed cells and showed improved accumulation in arthritic paws, demonstrating the superior target ability to RA tissues. Moreover, compared to free TOF, TOFL significantly improved the therapeutic efficacy, reduced the inflammatory cytokine expression and lipid peroxidation in synovial cells in the joint tissue of RA rats. Overall, these results indicate that TOFL served as the useful nanocarriers for RA-targeted therapy.