Five TNF inhibitors are now available for clinical use in RA, and all five are biological agents: etanercept, a TNF receptor fragment crystallizable (Fc) fusion protein (3); infliximab, an anti-TNFα chimeric monoclonal antibody (4); adalimumab and golimumab, anti-TNFα human monoclonal antibodies (5, 6); and certolizumab pegol, a pegylated anti-TNFα humanized antibody Fab’ fragment (7). The gene discussed is TNF; the disease is rheumatoid arthritis.