Nov 2018
Eltrombopag is an oral thrombopoietin (TPO)‐receptor agonist that induces proliferation and differentiation of megakaryocytes. Eltrombopag is approved for the treatment of chronic immune thrombocytopenia purpura (ITP) after insufficient response to standard therapy.
Approximately 5% of patients with previously‐untreated chronic lymphocytic leukaemia (CLL) and 25–30% of patients with previously‐treated CLL have thrombocytopenia (Tsang & Parikh, 2017). As thrombocytopenia is commonly seen in active CLL, the diagnosis of CLL‐associated ITP can be difficult.
ITP is a result of auto‐antibodies leading to platelet destruction. Conventional treatment is focused on targeting the immune destruction of platelets through the use of corticosteroids, immunoglobulins and immunosuppressive agents. Splenectomy is another effective treatment but is infrequently used.
Eltrombopag, an oral TPO‐receptor agonist, activates intracellular signal transduction, leading to an increase in differentiation and proliferation of bone marrow progenitor cells resulting in an increased platelet count.
In this phase II study, eltrombopag was evaluated as a treatment for thrombocytopenia in patients with CLL (NCT01168921).
This study highlights the effectiveness of eltrombopag in patients with CLL‐associated ITP who are refractory to standard ITP treatments. The response rate of 82% is encouraging and is similar to those seen in patients with chronic ITP.
Notably, the response rate to eltrombopag was lower in patients with CLL where thrombocytopenia was deemed not immune‐mediated.
As treatment options for CLL have evolved from cytotoxic chemotherapy to oral targeted therapies (Jain & O'Brien, 2016), further studies are warranted to assess the benefit of eltrombopag in the setting of thrombocytopenia associated with oral targeted therapies.
More here: onlinelibrary.wiley.com/doi...
Jackie
