Study of the Safety and Immunogenicity of Long-term GNR-069 Therapy in ITP Patients

Study Overview
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Brief Summary
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It is a phase III extension study to assess safety and immunogenicity of long-term therapy with GNR-069 in patients with idiopathic thrombocytopenic purpura

Detailed Description
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It is an extension study in patients with ITP who completed participation in RMP-ITP-III clinical trial. The study will be conducted in three stages: Transition visit - 1 day (transition of clinical trial participants from the RMP-ITP-III study to the RMP-ITP-III-X study); Treatment period - minimum 26 weeks; Follow-up period - 1 week. Patients will then be provided with the study therapy till the product market access with only safety data collection.

Official Title
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Extension Study of Long-term Safety and Immunogenicity of GNR-069 Patients With Idiopathic Thrombocytopenic Purpura Who Completed Phase 3 RMP-ITP-III Clinical Trial

Conditions
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Idiopathic Thrombocytopenic Purpura

Intervention / Treatment
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* Biological: GNR-069


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Completion of participation in the study RMP-ITP-III while maintaining the clinical effectiveness of romiplostim therapy Exclusion Criteria: Hypersensitivity to the components of the study drug or E. Coli proteins; Pregnancy or breastfeeding; Any diseases and conditions that, in the opinion of the Investigator, may hinder the patient's participation in the study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: GNR-069<br>Weekly subcutaneous injections of GNR-069 in the individually titrated dose. | Biological: GNR-069<br>* Once a week as a subcutaneous injection.<br>* Other names: romiplostim;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Frequency and severity of adverse events associated with the use of the GNR-069 | Adverse events will be assessed based on complaints, physical examination and laboratory data. | up to 29 weeks | 
| Number of undesirable events of particular interest in the study (Bleeding;Thrombotic/thromboembolic events) | The event of particular interest in this study are bleeding and thrombotic/thromboembolic events of any location. | up to 29 weeks | 
| Number of clinically significant bleeding on Visits 1-5 | The clinically significant bleeding will be considered events ≥ grade 2 according to CTCAE 5.0. | up to 29 weeks | 
| Number and proportion of the patient with antidrug antibodies. | The antidrug antibodies willl be characterized by their type, titer and neutralizing activity. | up to 29 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Frequency of the loss of the treatment response | Loss of the treatment response is assessed as absense of platelet increase ≥ 50,0 х 109/L on the 4 weeks treatment with maximal study drug dose. | up to 27 weeks | 
| Platelet count dynamics at Visits 1-5 | The platalets must be counted till week 5 | up to 5 weeks | 
| Сhange in ITP-BAT bleeding scores from baseline to week 27 | ITP-specific bleeding assessment tool (ITP-BAT) will be calculated at baseline and at week 27. | up to 27 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bleeding, Idiopathic thrombocytopenic purpura, ITP, Thrombocytopenia, Thrombocytopoiesis, Hemorrhagic syndrome, Petechial rash, Ecchymosis, Fc-peptide, Recombinant DNA technology, Thrombopoietin receptors, Platelet formation, Fc fragment of human immunoglobulin IgG 1, Low platelet count, ITP treatment, Platelets, Haemorrhage, Platelet destruction, Impaired thrombopoiesis, Megakaryocytes, Autoantibodies, Splenectomy, Cytotoxic, T cells, Thrombopoietin receptor agonists, Thrombopoietin receptor mimetic, TPO-RAs, romiplostim, Nplate