Biologics, including tocilizumab (a humanized anti-interleukin-6 receptor monoclonal antibody), rituximab (a chimeric anti-CD20 monoclonal antibody), or adalimumab (a humanized neutralizing anti-tumor necrosis factor monoclonal antibody), were used if the initial therapy failed to control the symptoms of HLH, especially among patients with MAS (Figure 3). This evidence concerns the gene IL6R and macrophage activation syndrome.