Evaluating the Pharmacokinetics and Pharmacodynamics of Romiplostim in Patients With Immune Thrombocytopenia (ITP)

Study Overview
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Brief Summary
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The objective of evaluating the pharmacokinetics and pharmacodynamics of romiplostim in patients with immune thrombocytopenia.

Official Title
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Evaluating the Pharmacokinetics and Pharmacodynamics of Romiplostim in Patients With Immune Thrombocytopenia (ITP)

Conditions
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Immune Thrombocytopenia (ITP)

Intervention / Treatment
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* Drug: Romiplostim


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosed with immune thrombocytopenia (ITP) for at least 6 months prior to signing the informed consent form (ICF). Subject is ≥ 18 years old and ≤ 70 years old while signing the ICF. Patients who have no response or relapsed after splenectomy. Or patients who have not been splenectomised and have completed at least 1 prior treatment for ITP. Excluded having previously received recombinant human thrombopoietin (rHuTPO) or any other thrombopoietin receptor agonist. The mean of 3 scheduled platelet counts taken during the screening period must be: < 30 ×10^9/L, with none >35×10^9/L. Exclusion Criteria: Any known history of bone marrow stem cell disorder. Any abnormal bone marrow findings other than typical of ITP. Any active malignancy. If prior history of cancer other than basal cell carcinoma or cervical carcinoma in situ, no treatment or active disease within 5 years prior to signing the ICF. Had received Eltrombopag, recombinant human thrombopoietin (rHuTPO) or other myeloproliferative leukemia (MPL) stimulation product. Received hematopoietic growth factors (e.g., granulocyte colony-stimulating factor, macrophage colony-stimulating factor, erythropoietin, interleukin-11) for any reason within 4 weeks prior to signing the ICF. Received any anti-malignancy agents (e.g., cyclophosphamide, 6-mercaptopurine, vincristine, vinblastine, interferon-alfa) for any reason within 8 weeks prior to signing the ICF. Received any monoclonal antibody drugs (e.g., rituximab) for any reason within 14 weeks prior to signing the ICF. Less than 4 weeks since end of any clinical trials about therapeutic drug or device for any indication prior to signing the ICF. Pregnant or breast feeding. In the opinions of the principal investigator or investigators, the patients are not suitable for participation in this trial.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1 mcg/kg AMG531<br>The administration of Romiplostim will be performed on Day 1 and 8 | Drug: Romiplostim<br> <br> * Other names: AMG531;|
| Experimental: 3 mcg/kg AMG531<br>The administration of Romiplostim will be performed on Day 1 and 8 | Drug: Romiplostim<br> <br> * Other names: AMG531;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of all adverse events including evaluation of antidrug antibody status |  | Up to 43 days after dosing |