Anti-tumor necrosis factor-α (TNFα) antibodies (infliximab, adalimumab, golimumab, and certolizumab), a soluble TNF receptor (etanercept), an anti-interleukin-6 receptor antibody (tocilizumab), and an inhibitor of T-cell costimulatory signaling (abatacept) are mainly used in biological therapy for RA in Japan. Here, TNF is linked to rheumatoid arthritis.