Infliximab is a purified, recombinant DNA-derived chimeric human-mouse IgG monoclonal antibody to TNF. It contains murine heavy (H) and light (L) chain variable regions (VH and VL, resp.), ligated to genomic human heavy and light chain constant regions. Infliximab can quickly form stable complexes with the human soluble or the membrane form of TNF and terminate the biological activity and signals of TNF. Infliximab was the first biologic agent shown to be efficacious in RA, AS and PsA.