Eltrombopag for the treatment of idiopathic thrombocytopenic purpura.

Strategies aimed at stimulating platelet production are a rational approach to the treatment of patients with primary immune thrombocytopenia, as, for many of them, the low platelet count is a consequence of ineffective megakaryopoiesis. Recently, intense clinical trial activity in immune thrombocytopenia has been reported for second-generation thrombopoietic agents. These novel molecules bear no structural resemblance to thrombopoietin, but still bind and activate the thrombopoietin receptor. One of these agents is eltrombopag (formerly SB497115), an orally available, small organic compound. Randomized trials have shown the short-term efficacy of eltrombopag in elevating the platelet count of most adult patients with immune thrombocytopenia unresponsive to at least one standard treatment. No significant adverse events were observed, but long-term safety data are still lacking. Ongoing studies will reveal the potential of this agent in the management of immune thrombocytopenia for long-term maintenance therapy, as well as its relative benefit compared with standard-of-care treatment.