Tocilizumab, a monoclonal antibody approved for several indications such as rheumatoid arthritis, giant cell vasculitis or cytokine release syndrome, targets the IL-6R and thus one of the major pathways to induce the transcription of the HAMP (for hepcidin-antimicrobial peptide) gene (37, 94, 95). The gene discussed is HAMP; the disease is rheumatoid arthritis.