Background: In 1988, the US Food and Drug Administration permitted low dose
methotrexate for the treatment of rheumatoid arthritis that would change the progression of the disease.
Methotrexate is a folic acid antagonist and its systemic use causes numerous side effects; including
hepatic toxicity. It would be preferable to deliver methotrexate by the topical route to reduce
side-effects along with ease of administration and reduced dosing frequency. So, nanoparticle
gel is a hopeful approach to treat rheumatoid arthritis.
Objective: The study aims to develop a nanoparticles gel containing novel natural polymer-based
methotrexate nanoparticles and evaluate its therapeutic potential on Complete Freund’s Adjuvant–
Induced Arthritis rat model and compare it to methotrexate and dexamethasone gel.
Materials and Methods: The five batches of methotrexate nanoparticles gel were prepared viz.
F1W2, F2W2, F3W2, F4W2 and methotrexate gel for the topical application by using different concentrations
of Carbopol 934 base and characterized for their evaluation parameters: homogeneity,
grittiness, pH, spread-ability, viscosity determination, and drug content studies. The arthritic potential
of methotrexate-nanoparticles gel was evaluated by Complete Freund’s Adjuvant–Induced
Arthritis rats model based on percent inhibition oedema and arthritic score.
Result and Discussion: Methotrexate nanoparticles gel significantly reduced the percentage inhibition
of oedema compared to methotrexate and dexamethasone gel. The therapeutic activity of nanoparticles
gel was found to be F3W2 ≥ F2W2 ≥ F1W2 ≥ F4W2 ≥ MTX gel. So, the optimized nanoparticle
gel formulation F3W2 can be effective in the treatment of rheumatoid arthritis.
Conclusion: The developed novel nanoparticles gel formulation can be a promising alternative to
existing methotrexate and dexamethasone gel.