MPL and idiopathic aplastic anemia: Eltrombopag (ELT), an oral thrombopoietin receptor agonist, can also lead to clinically significant improvements in blood counts in nearly half of the patients with aplastic anemia refractory to immunosuppression (8), increasing bone marrow cellularity, CD34+ count, and progenitor cells through a direct effect on marrow stem cells (9).