Avatrombopag (YM477) is a new oral thrombopoietin (TPO) receptor agonist, activating TPO receptor and increasing megakaryocytic proliferation/differentiation and platelet production.

Avatrombopag hydrochloride (AKR-501) is an orally active, nonpeptide agonist of the thrombopoietin (TPO) receptor with an EC 50 of 3.3 nM. It effectively mimics the biological activities of TPO, stimulating platelet production by activating the intracellular signaling system and facilitating the generation of platelets and megakaryocytes from hemopoietic precursor cells. Additionally, Avatrombopag hydrochloride serves as a substrate for cytochrome P450 (CYP) 2C9 and CYP3A.