AMG 531 Treatment of Thrombocytopenic Subjects With Immune (Idiopathic) Thrombocytopenic Purpura (ITP) Refractory to Splenectomy

Sponsor

Amgen (Industry)

Overall Status

Completed

CT.gov ID

NCT00102323

Collaborator

(none)

Enrollment

Arms

23.1

Actual Duration (Months)

Study Details

Study Description

Brief Summary

The purpose of this study is to evaluate the efficacy of AMG 531 in the treatment of thrombocytopenia in subjects with ITP as measured by the platelet response. This study will also evaluate changes in Patient Reported Outcomes and Health Resource Utilization due to treatment with AMG 531.

Condition or Disease	Intervention/Treatment	Phase
Thrombocytopenia Idiopathic Thrombocytopenic Purpura	Drug: Placebo Biological: AMG 531	Phase 3

Study Design

Study Type:

Interventional

Actual Enrollment :

63 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Double (Participant, Investigator)

Primary Purpose:

Treatment

Official Title:

A Randomized, Placebo Controlled Study Evaluating the Efficacy and Safety of AMG 531 Treatment of Thrombocytopenic Subjects With Immune (Idiopathic) Thrombocytopenic Purpura (ITP) Refractory to Splenectomy

Actual Study Start Date :

Mar 29, 2005

Actual Primary Completion Date :

Sep 1, 2006

Actual Study Completion Date :

Mar 1, 2007

Arms and Interventions

Arm	Intervention/Treatment
Placebo Comparator: Placebo	Drug: Placebo Weekly subcutaneous dosing based on screening weight and platelet count. Starting dose is at 1mcg/kg up to a maximum dose of 15mcg/kg. Placebo is supplied as a lyophilized power in a 5 mL single use glass vial.
Experimental: AMG 531 Active Investigational Product	Biological: AMG 531 Weekly subcutaneous dosing based on screening weight and platelet count. Starting dose is at 1mcg/kg up to a maximum dose of 15mcg/kg. AMG 531 is supplied in a 5 mL single use glass vial as a sterile, white, preservative-free, lyophilized powder.

Arm

Intervention/Treatment

Placebo Comparator: Placebo

Drug: Placebo

Weekly subcutaneous dosing based on screening weight and platelet count. Starting dose is at 1mcg/kg up to a maximum dose of 15mcg/kg. Placebo is supplied as a lyophilized power in a 5 mL single use glass vial.

Experimental: AMG 531

Active Investigational Product

Biological: AMG 531

Weekly subcutaneous dosing based on screening weight and platelet count. Starting dose is at 1mcg/kg up to a maximum dose of 15mcg/kg. AMG 531 is supplied in a 5 mL single use glass vial as a sterile, white, preservative-free, lyophilized powder.

Outcome Measures

Primary Outcome Measures

To evaluate the efficacy of AMG 531 in the treatment of thrombocytopenia in subjects with ITP as measured by durable platelet response during the last 8 weeks of treatment and other platelet response parameters [Last 8 weeks of treatment]

Secondary Outcome Measures

To evaluate the overall safety of AMG 531 [Entire study duration plus follow up period]
To evaluate the possible reductions in concurrent ITP therapies while receiving AMG 531 [Entire study duration]
To evaluate changes in Patient Reported Outcomes and Health Resource Utilization due to treatment with AMG 531 [Entire study duration]

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Diagnosis of ITP according to American Society of Hematology (ASH) guidelines (Appendix F)
Have had a splenectomy for the treatment of ITP greater than or equal to 24 weeks prior to study entry
Subjects greater than 60 years of age must have a documented history of chronic ITP with a bone marrow report to confirm the diagnosis
The platelet count (calculated from the mean of the 2 counts taken during the screening and pre-treatment periods) must be:
- less than 30 x 10^{9/L for those subjects not receiving any ITP therapy, with no
  count greater than 35 x 10}9/L,
- less than 50 x 10^{9/L for those subjects receiving a constant dose schedule of
  corticosteroids, azathioprine or danazol with no count greater than 55 x 10}9/L
A serum creatinine concentration less than or equal to 2 mg/dl(less than or equal to 176.8 µmol/L)
Adequate liver function, as evidenced by a serum bilirubin less than or equal to 1.5 times the laboratory normal range
Hemoglobin greater than 11.0 g/dL
Written informed consent (see Section 12.1)

Exclusion Criteria:

Any known history of bone marrow stem cell disorder (Any abnormal bone marrow findings other than those typical of ITP must be approved by Amgen before a subject may be enrolled in the study)
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 randomization
Documented diagnosis of arterial thrombosis (i.e., stroke, transient ischemic attack or myocardial infarction) in the past year
History of venous thrombosis (i.e., deep vein thrombosis, pulmonary embolism) including those subjects who are on ant-coagulation therapy
Unstable or uncontrolled disease or condition related to or impacting cardiac function (e.g., unstable angina, congestive heart failure [NYHA greater than class II], uncontrolled hypertension [diastolic greater than 100 mmHg] or cardiac arrhythmia)
Have 3 or more of the following predisposing factors for thromboembolic events: diabetes; smoker; using oral contraceptives; on estrogen therapy; known positive for anti-phospholipid antibodies; hypertriglyceridemia; hypercholesteremia (greater than 240 mg/dL); treatment for hypertension
Known positive test for human immunodeficiency virus (HIV) infection or hepatitis C virus
Currently receiving any treatment for ITP except corticosteroids, azathioprine or danazol administered at a constant dose and schedule
IV Ig or anti-D Ig within 2 weeks before the screening visit
Rituximab (for any indication) within 14 weeks before the screening visit or anticipated use during the time of the proposed study
Received hematopoietic growth factors, including IL-11 (oprelvekin) within 4 weeks before the screening visit
Past or present participation in any study evaluating PEG-rHuMGDF, recombinant human thrombopoietin (rHuTPO), AMG 531 or related platelet product
Received any aklylating agents within 8 weeks before the screening visit or anticipated use during the time of the proposed study
Less than 4 weeks since receipt of any therapeutic drug or device that is not FDA approved for any indication before the screening period
Less than 8 weeks since major surgery
Pregnant or breast feeding
Subjects of reproductive potential who are not using adequate contraceptive precautions, in the judgment of the investigator
Known hypersensitivity to any recombinant E coli-derived product
Concerns for subject's compliance with the protocol