Abstract Number: PB0821
Meeting: ISTH 2021 Congress
Theme: Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies » Acquired Thrombocytopenias
Background: Both recombinant human thrombopoietin (rhTPO) and eltrombopag are recommended second-line drugs for the treatment of immune thrombocytopenia (ITP).
Aims: This double-blind, double-dummy controlled study aims to explore which drugs are more suitable for the rapid increase of platelets in Chinese ITP patients.
Methods: 96 patients were 1:1 randomly assigned to receive eltrombopag 25 mg/day or rhTPO 300 U/kg for 2 weeks.
Results: 
Response rate. The proportion of patients achieving platelet counts 50×109/L or more at day 15 (a); the proportion of patients achieving CR, R or NR at day 15 (b); CR: platelet count ≥100×109/L and absence of bleeding; R: platelet count≥30×109/L and at least 2-fold increase of the baseline platelet count and absence of bleeding; NR: platelet count not achieved 50×109/L or 2-fold increase of the baseline platelet count or with bleeding. The proportion of patients whose platelets reached≥50×109/L at least once during the treatment (c); the proportion of patients whose platelets increased twice more than baseline at least once during the treatment (d).*P＜0.05；**P＜0.005；***P＜0.001.
Median platelet counts (a) and mean changes in platelet counts (b) at every visit. Median platelet counts at every visit are shown with IQR, and mean changes in platelet counts from baseline at every visit are shown with 95% CIs; *P＜0.05；**P＜0.005；***P＜0.001.
The primary endpoint was the proportion of patients achieving platelet counts ≥50×109/L at day 15. Secondary endpoints included the platelet response, time to response, and adverse events during treatment. The primary endpoint was achieved in 75% (36/48) of patients in the rhTPO group and 43.75% (21/48) in the eltrombopag group, p=0.003. Complete response was achieved in 64.58% of patients in the rhTPO group vs 25.00% of patients in the eltrombopag group. The proportion of patients whose platelets increased twice more than baseline or reached ≥50×109/L at least once was higher in the rhTPO group on days 9, 12, and 15. The time to increase the platelets twice more than the baseline (p=0.048) or achieve the platelets ≥50×109/L (p=0.048) was shorter in the rhTPO group. However, after treatment, the platelets dropped to the baseline within 1 week in the rhTPO group, while platelets dropped slowly in the eltrombopag group. Adverse events have no significant difference between the two groups.
Conclusions: Compared to the rhTPO, the dose of 25mg eltrombopag may be insufficient to rapidly increase platelets to a safe level in Chinese ITP patients. This study is registered with ClinicalTrials.gov, number NCT03771378.
To cite this abstract in AMA style:
Mei H, Xu M, Yuan G, Zhu F, Guo J, Huang R, Qin J, Lv T, Qin F, Cai H, Yin P, Qin T, Hu Y. A Multicenter Double-blind, Double-dummy, Randomized Study of rhTPO vs Eltrombopag in the Treatment of Chinese Immune Thrombocytopenia [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/a-multicenter-double-blind-double-dummy-randomized-study-of-rhtpo-vs-eltrombopag-in-the-treatment-of-chinese-immune-thrombocytopenia/. Accessed December 6, 2023.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/a-multicenter-double-blind-double-dummy-randomized-study-of-rhtpo-vs-eltrombopag-in-the-treatment-of-chinese-immune-thrombocytopenia/