Long-term Study of Romiplostim in Thrombocytopenic Pediatric Patients With Immune Thrombocytopenia (ITP)
Condition: Immune Thrombocytopenia
MeSH terms: Thrombocytopenia; Purpura, Thrombocytopenic, Idiopathic
Intervention: Romiplostim
Intervention description: Romiplostim subcutaneous weekly injection
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Intervention model: Single Group Assignment
Masking: None (Open Label)
Enrollment: 203.0
Sex: All
Minimum age: 1 Year
Maximum age: 18 Years
Healthy volunteers: No
Keywords: Pediatric; Immune Thrombocytopenia; Amgen

Summary:

      This is a phase 3b single arm, open label, multicenter study describing the percentage of
      time pediatric participants with ITP have a platelet response while receiving romiplostim,
      defined as a platelet count ≥ 50 x 10^9/L in the absence of ITP rescue medications for the
      past 4 weeks.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Diagnosis of primary ITP according to The American Society of Hematology (ASH)
             Guidelines at least 6 months before screening, regardless of splenectomy status

          -  Age ≥ 1 year and < 18 years of age

          -  Refractory to prior ITP therapy, relapsed after at prior ITP therapy, or be ineligible
             for other therapies. Examples of prior therapy include: corticosteroids, intravenous
             Immunoglobulin (IVIG), anti-D immunoglobulin, platelet transfusions.

          -  Platelet count ≤ 30 x10^9/L or is experiencing uncontrolled bleeding

          -  Has provided informed consent before any study-specific procedure;

          -  Adequate hematologic, renal, and liver function during screening:

               -  Hemoglobin > 10.0 g/dL

               -  Serum creatinine ≤ 1.5 x the upper limit of normal (ULN)

               -  Total serum bilirubin ≤ 1.5 x the ULN

               -  Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 3.0 x the
                  ULN

          -  For the EU, Switzerland and Turkey protocol supplement, subject must agree to a
             scheduled bone marrow biopsy and aspirate at Year 1 or Year 2 following romiplostim
             treatment and any unscheduled biopsies if clinically indicated

          -  For the EU, Switzerland and Turkey protocol supplement, a reticulin grade of 0, 1, 2,
             or 3 according to the modified Bauermeister grading scale, as assessed by central
             laboratory from a bone marrow biopsy performed within 1 year prior to planned first
             dose of romiplostim or consent to a pre-treatment bone marrow biopsy and aspirate
             prior to planned first dose of romiplostim

        Exclusion Criteria:

          -  History of a 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)

          -  Prior bone marrow transplant or peripheral blood progenitor cell transplant

          -  Active or prior malignancy except non-melanoma skin cancers within the last 5 years

          -  History of myelodysplastic syndrome

          -  History of bleeding diathesis

          -  History of congenital thrombocytopenia

          -  History of Hepatitis B, Hepatitis C or human immunodeficiency virus (HIV)

          -  History of systemic lupus erythematosus, Evans syndrome, or autoimmune neutropenia

          -  History of antiphospholipid antibody syndrome or known positive for lupus
             anticoagulant

          -  History of disseminated intravascular coagulation, hemolytic uremic syndrome, or
             thrombotic thrombocytopenic purpura

          -  History of venous thromboembolism or thrombotic events

          -  Previous use of romiplostim or previous use of eltrombopag within 4 weeks of
             enrollment

          -  Previous use of pegylated recombinant human megakaryocyte growth and development
             factor (PEG-rHuMGDF), recombinant human thrombopoietin (rHuTPO) or any other platelet
             producing agent

          -  Rituximab (for any indication) or 6-mercaptopurine within 8 weeks of enrollment, or
             anticipated use at any time during the study

          -  Splenectomy within 4 weeks of the screening visit

          -  Alkylating agents within 8 weeks before the screening visit or anticipated use during
             the time of the proposed study

          -  Vaccinations known to decrease platelet counts within 8 weeks before the screening
             visit

          -  Currently enrolled in another investigational device or drug study, or less than 30
             days since ending investigational study

          -  Will have investigational procedures while enrolled on study

          -  Female subject of child bearing potential (defined as having first menses) not willing
             to use, in combination with her partner highly effective methods of birth control
             during treatment and for 1 month after the end of treatment

          -  Subject is pregnant or breast feeding, or might become pregnant within 1 month after
             the end of treatment

          -  Subject has known hypersensitivity to any recombinant Escherichia coli derived product
             (eg, Infergen®, Neupogen®, somatropin, and Actimmune®)

          -  Has previously enrolled into this study

          -  Will not be available for protocol-required study visits or procedures, to the best of
             the subject's and investigator's knowledge

          -  Any kind of disorder that, may compromise the subject to give written informed consent
             and/or to comply with all required study procedures