Nanostructured Lipid Carrier–based Topical Gel of Iguratimod for the Management of Rheumatoid Arthritis: Formulation Strategies, Evaluation and Therapeutic Perspectives

Rheumatoid arthritis (RA) is a long-term autoimmune disease that causes swelling in the joints, breaks down cartilage, and slowly destroys bone, leading to joint damage and trouble moving. The main treatment for RA is drugs called DMARDs, and Iguratimod is one of these that works by reducing inflammation and controlling the immune system. But taking Iguratimod by mouth for a long time can cause side effects and some people don’t take it as they should. Using a cream or ointment with the drug could help treat the affected joints directly while keeping the medicine out of the rest of the body. However, Iguratimod doesn’t mix well with water and doesn’t easily pass through the skin, making it hard to use this way. Nanostructured lipid carriers (NLCs) are advanced nanocarriers made from lipids. They have shown great promise in improving how well drugs dissolve, stay stable, and get through the skin. When NLCs are added to topical gels, they help the drug stay on the skin longer, release slowly, and be more comfortable for patients. This review covers the disease process of rheumatoid arthritis, how the drug Iguratimod works, the problems with older treatments, and why using Iguratimod in NLC-based gels could be a better option. It also looks at how these gels are made, how they're tested, the challenges involved, and what might come next.