Eltrombopag was first reported as a thrombopoietin receptor (TPO-R) agonist for the treatment of immune thrombocytopenia (ITP), and approved by the U.S. Food and Drug Administration for the treatment of chronic ITP and aplastic anemia in 2008 and 2014, respectively [44,45,46]. Here, MPL is linked to autoimmune thrombocytopenic purpura.