hydroxychloroquine + leflunomide + methotrexate

This is a combination therapy consisting of three conventional synthetic disease-modifying antirheumatic drugs (csDMARDs): hydroxychloroquine, leflunomide, and methotrexate. Each drug has a distinct mechanism of action targeting immune-mediated inflammation in diseases such as rheumatoid arthritis. Methotrexate inhibits dihydrofolate reductase, reducing DNA synthesis and immune cell proliferation. Leflunomide inhibits dihydroorotate dehydrogenase, blocking pyrimidine synthesis and T-cell activation. Hydroxychloroquine interferes with antigen presentation and toll-like receptor signaling in immune cells. This triple therapy is used when monotherapy or double therapy does not adequately control disease activity[1][2]. The combination aims to maximize efficacy by leveraging complementary mechanisms while monitoring for additive toxicity.