Anti-inflammatory biologic agents, including but not limited to TNF-α inhibitors (e.g., adalimumab), interleukin-1 (IL-1) inhibitors (e.g., canakinumab), and IL-6 inhibitors (e.g., tocilizumab), have been used in treating rheumatoid arthritis (RA) and other inflammatory diseases. This evidence concerns the gene IL6 and rheumatoid arthritis.