TNF and rheumatoid arthritis: At present, the drugs used to treat RA range from nonsteroidal anti-inflammatory drugs (NSAIDs) to disease-modifying antirheumatic drugs (DMARDs) such as methotrexate as the main treatment approach, while biological DMARDs such as antitumor necrosis factor (TNF), interleukin (IL)-1, and IL-6 are usually considered only when patients fail to respond to conventional DMARDs.