IL6 and rheumatoid arthritis: Disease-modifying antirheumatic drugs (DMARDs), including conventional DMARDs (e.g., methotrexate and leflunomide), targeted DMARDs (e.g., Janus kinase inhibitors) and biological DMARDs (e.g., tumor necrosis factor inhibitors, IL-6 inhibitors, IL-1 inhibitors and T-cell immunomodulators), are the mainstay for treating RA [6].