P3 Study to Evaluate Efficacy and Safety of AMG 531 in Thrombocytopenic Japanese Subjects With Immune (Idiopathic) Thrombocytopenic Purpura

Phase 3

Completed

• Conditions: Idiopathic Thrombocytopenic Purpura
• Interventions: Drug: Placebo; Drug: AMG 531

• Registration Number: NCT00603642
• Lead Sponsor: Amgen

Brief Summary

The purpose of this study is to evaluate the efficacy and safety of AMG 531 compared with placebo in thrombocytopenic Japanese subjects with immune (idiopathic) thrombocytopenic purpura (ITP) .

Detailed Description

Not available

Study Timeline

• Study Start: 2007-10-01
• Study First Submitted: 2008-01-17
• Study First Submitted QC: 2008-01-17
• Study First Posted: 2008-01-29
• Primary Completion: 2009-04-13
• Study Completion: 2009-04-13
• Results First Submitted: 2010-11-18
• Results First Submitted QC: 2010-11-18
• Results First Posted: 2010-12-10
• Status Verified: 2022-11
• Last Update Submitted: 2022-11-04
• Last Update Posted: 2022-11-08

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 34

Inclusion Criteria

• Japanese patients with diagnosis of ITP according to the diagnostic criteria proposed by Research Committee for Idiopathic Hematopoietic Disorders of the Ministry of Health, Labour and Welfare [MHLW] (revised in 1990) at least 6 months before the first screening visit
• The mean of the 3 scheduled platelet counts taken at the scheduled visits during the screening period must be ≤ 30 x 10^9/L, with no individual count > 35 x 10^9/L
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2
• Subjects must be ≥ 20 years of age at the time of obtaining the informed consent
• Have received at least 1 prior treatment for ITP
• If known Helicobacter pylori positive, having completed one course of Helicobacter pylori eradication therapy at least 12 weeks before the first screening visit
• A hemoglobin value taken at scheduled visit during the screening period must be ≥ 10 g/dL
• A serum creatinine concentration taken at scheduled visit during the screening period must be ≤ 2 mg/dL
• Adequate liver function, as evidenced by a total bilirubin taken at scheduled visit during the screening period ≤ 1.5 times of the upper limit of the normal range (except for patients with a confirmed diagnosis of Gilbert's Disease) or an alanine aminotransferase and aspartate aminotransferase taken at the screening visit ≤ 3 times of the upper limit of the normal range

Exclusion Criteria

• Any known history of bone marrow stem cell disorder. Any abnormal bone marrow findings other than those 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 before the first screening visit.
• Documented diagnosis of arterial thrombosis (eg, stroke, transient ischemic attack, or myocardial infarction); history of venous thrombosis (eg, deep vein thrombosis, pulmonary embolism) and receiving anticoagulation therapy at the first screening visit.
• Documented diagnosis of anti phospholipid antibody syndrome
• Currently receiving any treatment for ITP except oral corticosteroids, azathioprine and/or danazol administered at a constant dose and schedule from at least 4 weeks prior to the first screening visit
• Received intravenous immunoglobulin, anti D immunoglobulin, or any drug administered to increase platelet counts (eg, immunosuppressants except azathioprine) within 2 weeks before the first screening visit
• Have had a splenectomy for any reason within 12 weeks before the first screening visit
• Past or present participation in any study evaluating pegacaristim (polyethylene glycol-conjugated recombinant human megakaryocyte growth and development factor, KRN9000), Eltrombopag (SB 497115), recombinant human thrombopoietin, AMG 531, or other Mpl stimulation product
• Received hematopoietic growth factors (eg, granulocyte colony stimulating factor, macrophage colony stimulating factor, erythropoietin, interleukin 11) for any reason within 4 weeks before the first screening visit
• Received any anti malignancy agents (eg, cyclophosphamide, 6 mercaptopurine, vincristine, vinblastine, Interferon alfa) for any reason within 8 weeks before the first screening visit
• Received any monoclonal antibody drugs (eg, rituximab) for any reason within 14 weeks before the first screening visit
• Less than 4 weeks since receipt of any therapeutic drug or device that is not MHLW approved for any indication before the first screening visit
• Pregnant or breast feeding
• Subjects of reproductive potential who are not using adequate contraceptive precautions, in the judgment of the investigator
• Known severe drug hypersensitivity
• Concerns for subject's compliance with the protocol

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	-
AMG 531	AMG 531	Double blinded placebo-controlled study

Primary Outcome Measures

Name	Time	Method
Weeks With Weekly Platelet Response	12 weeks (Weeks 2 - 13)	Number of weeks with weekly platelet response. A weekly platelet response is defined as a platelet count of ≥ 50 x 10\^9/L on a weekly scheduled dose day from week 2 to week 13.

Secondary Outcome Measures

Name	Time	Method
Weeks With Platelet Count Between 50 and 200	12 weeks (Weeks 2 - 13)	Number of weeks with platelet count between 50 x 10\^9/L and 200 x 10\^9/L inclusive during week 2 to week 13.
Change From Baseline in Mean of Last 4 Weekly Platelet Counts	12 weeks (Weeks 2 - 13)	Change from baseline in the mean of the last 4 weekly platelet counts from week 2 to week 13.
Rescue Medication(s)	12 weeks (Weeks 2 - 13)	Requirement for rescue medication(s) during treatment by the participant
Increased Platelet Count From Baseline of at Least 20 x 10^9/L	Baseline, 12 weeks (Weeks 2 - 13)	An increase in platelet count of at least 20 x 10\^9/L from baseline within the participant during the treatment period. Increase was calculated as the maximum observed platelet count during the treatment period minus the baseline platelet count.