Trial Information

An Open Label Phase II Pilot Study of Hybrid ImmunoTherapy(ATG/Dexamethasone/Etoposide) for Hemophagocytic LymphoHistiocytosis:HIT-HLH

Hemophagocytic lymphohistiocytosis (HLH) is a rare immunological disorder first recognized
almost 70 years ago.(1) Genetic and animal studies have indicated that the familial form of
HLH is clearly due to a deficiency of cytotoxic killing. Patients with HLH present with a
potentially fatal syndrome of 'hyperimmunity.' These patients have severe inflammation,
associated with cytopenias and variably severe bone marrow, liver, or CNS damage. Tissue
damage and mortality appear to be due to hypercytokinemia related to persistent immune
hyperactivation. An animal model of HLH and correlative human studies all suggest that
excessive and abnormal activation of T cells drives the pathophysiology of this disorder,
and that suppressing this excessive activation is critical for successful therapy of HLH. It
is believed a combination of the two proven induction regimens for hemophagocytic
lymphohistiocytosis (HLH) (anti-thymocyte globulin (ATG)- and etoposide-based) will result
in response rates and overall survival rates at eight weeks which are comparable or better
than the current standard of care (induction therapy per the HLH-94 protocol).