Development and in vivo evaluation of therapeutic phytosomes for alleviation of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease associated with progressive articular damage, functional loss and comorbidity. Conventional RA therapy requires frequent dosing and prolonged use, and usually results in poor efficacy and severe toxicity. In the current study, for the first time, we describe a combination strategy using phytosomes co-loaded with curcumin (CUR) and leflunomide (LEF) to improve the clinical outcomes of RA therapy. Exploiting 23 factorial design, various compositions of CUR and LEF co-loaded phytosomes (CUR/LEF-phytosomes) were successfully prepared and were extensively characterized (e.g., particle size, zeta potential, drugs encapsulation efficiency, morphology, DSC, FTIR and release kinetics). The optimal CUR/LEF-loaded phytosomes (F2) demonstrated high stability and spherical morphology with a particle size of ca. 760 nm and negative zeta potential value of -55.7, high entrapment for both drugs, and sustained release profile of the entrapped medications. In vivo, oral administration of the CUR/LEF-phytosomes (F2) in arthritic rats resulted in significant reduction of paw swelling and inflammatory markers, compared to the free drugs and their physical mixture. Histopathological examination revealed significant improvement in phytosomes-treated animal group with no signs of arthritis. CUR/LEF-loaded phytosomes provide an auspicious strategy for alleviation of RA.