A Study of Eltrombopag and Recombinant Human Thrombopoietin In Primary Immune Thrombocytopenia

Interventions: Drug: Recombinant human thrombopoietin (rh-TPO)
Drug: Eltrombopag

Brief Summary: Thrombopoietin Receptor Agonists (TPO-ra) are novel treatments for patients with refractory Primary Immune Thrombocytopenia (ITP). Rh-TPO and eltrombopag increase the number of platelets through different mechanism. If there is cross-resistance between 2 drugs for the treatment of adult ITP is still no answer. The purpose of this study is to investigate the efficacy and safety of switching eltrombopag and Rh-TPO in adults with ITP.

Detailed Description: Non-interventional study. Patients who fail previous steroids and receive rh-TPO and then switch to EPAG or vice versa will be enrolled. The reason for switch will be recorded. Patients in the rh-TPO group were given rh-TPO 300 U/kg once daily for 21 days, and those in the eltrombopag group were given eltrombopag 50mg once daily for 6 weeks. Rh-TPO and eltrombopag were terminated any time the platelet counts increased above 100 × 10\^9/L in the rh-TPO group and 300 × 10\^9/L in the eltrombopag group. The efficacy, safety, and patient/physician preference will be assessed and compared between the two agents.

Recruitment & Eligibility

Inclusion Criteria

1.18 years or older

2.Primary ITP

3.Platelet count ≤ 30 × 109/l

4.Normal neutrophils, reticulocyte count, creatinine and liver enzyme values

5.Available follow-up of 2 months at least for each period

6.Failed initial glucocorticosteroid treatment

7.Unwillingness to accept splenectomy or failed splenectomy

Exclusion Criteria

HIV, hepatitis B or C, Helicobacter pylori infection
Malignancy
Congenital or acquired immunologic deficit
History of thrombosis plus two or more risk factors
Nursing or pregnant women
Abnormal liver and renal functions: AST/ALT/total bilirubin ≥1.5 × ULN, creatinine ≥1.5 mg/dl
Severe heart and lung dysfunctions -

Arm && Interventions

Group	Intervention	Description
Recombinant human thrombopoietin (rh-TPO) group	Recombinant human thrombopoietin (rh-TPO)	Patients who fail previous steroids and eltrombopag and then switch to Rh-TPO will be enrolled. The reason for switch will be recorded. Patients will be given rh-TPO 300 U/kg once daily for 21 days. Rh-TPO will be terminated any time the platelet counts increased above 100 × 10\^9/L. The efficacy, safety, and patient/physician preference will be assessed.
Eltrombopag group	Eltrombopag	Patients who fail previous steroids and rh-TPO and then switch to eltrombopag will be enrolled. The reason for switch will be recorded. Patients will be given eltrombopag 50mg once daily for 6 weeks. Eltrombopag will be terminated any time the platelet counts increased above 300× 10\^9/L.The efficacy, safety, and patient/physician preference will be assessed.

Primary Outcome Measures

Name	Time	Method
Response Rate at 6 Weeks After Switching	6 weeks	The percentage of patients who have reached platelet count ≥ 50×10\^9/L at 6 weeks after switching.

Secondary Outcome Measures

Name	Time	Method
Number of Participants With Bleeding Events	6 weeks	Number of participants with bleeding events of the two groups during 6 weeks after switching
Treatments Associated Adverse Events	6 weeks	Adverse event/serious adverse event associated with study drugs during 6 weeks after switching
Reasons of Switching	6 weeks	Reasons of switching eltrombopag and rh-TPO will be recorded, including lack of efficacy, patient preference, side effects, platelet count fluctuation
TOR (Time to Response)	6 weeks	The time to achieve platelet count ≥ 50×10\^9/L after switching.
DOR (Duration of Response)	6 weeks	The duration of achieving platelet count ≥ 50×10\^9/L after switching.