Efficacy and Safety of rhTPO and Eltrombopag in Patients With Primary Immune Thrombocytopenia (ITP)

Primary immune thrombocytopenia (ITP) is an acquired autoimmune hemorrhagic disease. ITP patients have an increased risk of bleeding and the clinical symptoms are petechia, ecchymosis, organ hemorrhage and even life‐threatening bleeding. The mortality rate in ITP is increased approximately 60% compared with age‐ and sex matched comparisons, bleeding is one of the leading causes of death, thus treating and preventing bleeding is particularly important for those patients. In most cases, platelet count is negatively correlated with the severity of bleeding. Correcting low platelets is the main measure to prevent bleeding in patients with ITP. Recombinant human thrombopoietin (rhTPO), a full‐length glycated TPO, is a recombinant form of c‐Mpl ligand that competes with endogenous TPO for binding to TPO receptors (TPO‐R, c‐Mp0), many clinical trials have shown that rhTPO can efficiently and safely stimulate platelet production, increase peripheral blood platelet count. The State Food and Drug Administration approved the drug as the second‐line treatment for patients with ITP in 2005. Eltrombopag is an oral, synthetic non‐peptide small molecule human thrombopoietin receptor agonist approved by the US FDA in November 2008 for the treatment of patients with chronic ITP, which were inefficiently by use of glucocorticoids, immunoglobulin or splenectomy. However, pharmacokinetic study of eltrombopag showed that Asians have twice the drug exposure rate than non‐Asians, so eltrombopag may have different effects in different populations. Therefore, this trial will compare the efficacy and safety of intravenous rhTPO or oral use of eltrombopag after 14 days of treatment in Chinese ITP patients.