Transdermal release of methotrexate by cationic starch/poly(vinyl alcohol)-based films as an approach for rheumatoid arthritis treatment

Methotrexate (MTX) is a common drug used for rheumatoid arthritis (RA) treatment; however, a series of adverse effects associated with its oral or subcutaneous administration is reported. Transdermal delivery of MTX is an alternative to abate these issues, and the use of drug delivery systems (DDS) based on polymeric films presents an impressive potential for this finality. Based on this, in this study, we report the preparation of films made by cationic starch (CSt), poly(vinyl alcohol) (PVA), and chondroitin sulfate (ChS) to incorporate and release MTX, as well as the in vivo evaluation in model of rheumatoid arthritis in mice. CSt/PVA and CSt/PVA/ChS-based films (with and without MTX) were prepared using a simple protocol under mild conditions. The films loaded with 5 w/w-% of MTX exhibited appreciable drug loading efficiency and distribution. The MTX permeation through the layers of porcine skin demonstrated that most of the drug permeated was detected in the medium, suggesting that the formulation can provide a systemic absorption of the MTX. In vivo studies performed in an arthritis-induced model in mice demonstrated that the MTX-loaded films were able to treat and attenuate the symptoms and the biochemical alterations related to RA (inflammatory process, oxidative stress, and nociceptive behaviors). Besides, the pharmacological activity of MTX transdermally delivery by the CSt/PVA and CSt/PVA/ChS films was comparable to the MTX orally administered. Based on these results, it can be inferred that both films are prominent materials for incorporation and transdermal delivery of MTX in a practical and non-invasive manner.