Paroxysmal nocturnal hemoglobinuria-phenotype cells predict a good response to eltrombopag in patients with refractory aplastic anemia.

To identify factors affecting responsiveness to eltrombopag (EPAG), we retrospectively analyzed 38 aplastic anemia patients treated with EPAG who were refractory (n = 29) or showed an inadequate response (n = 9) to conventional therapies. The efficacy was evaluated at 16 weeks after starting EPAG and at any given time when the best response was achieved. Hematologic responses were observed in 15 patients (39%) at week 16 and in 25 (66%) at any given time. Ten of 19 (53%) achieved transfusion independence. A univariate analysis revealed the presence of PNH-phenotype cells and the relatively higher platelet counts as associated with a good response to EPAG.