TNF and rheumatoid arthritis: Indeed, current treatments, such as disease-modifying anti-rheumatic drugs (DMARDs), including non-biologic agents (e.g. methotrexate) and biologic agents (e.g. anti-TNF-α monoclonal antibodies), often fail to achieve full remission in RA patients or their effects on RA-associated pain are not well examined [[3], [4], [5]].