TNF and rheumatoid arthritis: The need for treatment beyond TNF blockers in RA has become clear since 25% to 40% of patients in clinical trials fail to achieve an ACR-20 (American College of Rheumatology 20% improvement criteria) response [2-4] and a proportion of patients experience treatment-limiting side effects or continue to experience a residual level of disease activity or show flares under anti-TNF therapy.