TPO and autoimmune thrombocytopenic purpura: Three TPO-RAs have been approved for use in the European Union since 2009, 2010 and 2019, respectively, for patients with ITP who are refractory to initial therapies: [35–37] romiplostim (Nplate®; once-weekly subcutaneous injection; Amgen, USA) for patients with primary ITP, eltrombopag (RevoladeTM; once-daily oral; Novartis, Switzerland) for patients with persistent/chronic ITP, and avatrombopag (Doptelet®; once-daily oral; Swedish Orphan Biovitrum AB, Sweden) for patients with primary chronic ITP.