Subjects with hemophagocytic lymphohistiocytosis (HLH) often have life-threatening complications at the time of diagnosis resulting from excessive inflammation. This excessive inflammation is driven by abnormally high levels of cytokines--proteins involved in inflammation. Standard therapy for HLH does not directly target these cytokines. Tocilizumab is a medicine that blocks one of the cytokines that is elevated in patients with HLH.~This is an open-label single-arm uncontrolled trial with biologic endpoint. This study will use tocilizumab in subjects with HLH and high cytokine levels in an attempt to decrease the damage caused by these proteins. All subjects will receive standard therapy, in addition to tocilizumab. We hypothesize the tocilizumab will decrease levels of certain important cytokines. This may make it easier to treat subjects with HLH overall.~TCZ will be administered as a single dose (8mg/kg) intravenously. Eligible subjects will be inpatients at the Children's Hospital of Philadelphia (CHOP) main campus. 10 subjects with HLH will be enrolled. All subjects will be initiated on standard HLH-directed treatment. Cytokine levels [including serum interferon (IFN-γ) and interleukin (IL-6)] will be monitored, in addition to other laboratory and clinical markers of HLH disease activity.
This study seeks to determine the efficacy of tocilizumab (TCZ) in patients with hemophagocytic lymphohistiocytosis (HLH) and high cytokine levels (proteins involved in inflammation) in an attempt to decrease the damage caused by these proteins; and secondarily to assess its safety and impact on disease activity.