Rheumatoid arthritis (RA) is a chronic inflammatory disease with progressive joint damage. Until recently, non-steroidal anti-inflammatory drugs (NSAIDs), followed by traditional disease-modifying anti-rheumatic drugs (DMARDs), were considered the treatments of choice. However, many patients fail to gain a satisfactory response to DMARDs. Tumor necrosis factor (TNF) is an important inflammatory mediator that plays a crucial role in RA. The TNF antagonist (Remicade) was approved by the Japan Ministry of Health in July 2003. It is thought that progression of joint damage and functional disability are lowered by TNF antagonists. Ongoing post-marketing surveillance of the TNF antagonist for serious adverse events is necessary to determine the true incidence rates, and whether a reassessment of the overall risk-benefit ratio of TNF antagonist will be required. This paper describes the clinical and radiological efficacy of Remicade.