Exploratory Multi-centre Trial In Patients With ET Treated With XAGRID®

Study Overview
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Brief Summary
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This study is hypothesis-generating to explore the impact of JAK2 (V617F) mutation status on the treatment response to anagrelide hydrochloride

Official Title
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An Exploratory, Observational, Multicentre Study to Investigate the Impact of the Presence of JAK2 (V617F) Mutation on Treatment Response in Patients With Essential Thrombocythaemia Treated With XAGRID® (Anagrelide Hydrochloride)

Conditions
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Essential Thrombocythemia (ET)

Intervention / Treatment
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* Drug: Anagrelide hydrochloride


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients must be able to understand and willing to participate in the study, and provide a personally dated and signed written informed consent form. Patients must have a confirmed diagnosis of ET according to the World health Organisation's criteria. ET patients who are uncontrolled, in the Investigator's opinion, by first-line (or previous) cytoreductive treatment for efficacy or tolerance reasons. Patients who have either commenced treatment with anagrelide hydrochloride in the last 7 days or for whom a decision has been documented to commence treatment with anagrelide hydrochloride Exclusion Criteria: Patients for whom treatment with anagrelide hydrochloride is contraindicated, according to the current XAGRID SmPC. Known or suspected intolerance or hypersensitivity to the product, closely related compounds, or any of the stated ingredients. Patients participating in an interventional research study. Patients on combination therapy or for whom there is an intention to treat with other cytoreductive agents e.g., hydroxyurea, interferon. Patients can however use aspirin and other anti-aggregatory products at the Investigator's discretion.
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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| JAK2 Positive Participants<br> | Drug: Anagrelide hydrochloride<br>* 0.5 mg hard capsules, dosing decisions will be made by the treating physician<br>* Other names: Xagrid;|
| JAK2 Negative Participants<br> | Drug: Anagrelide hydrochloride<br>* 0.5 mg hard capsules, dosing decisions will be made by the treating physician<br>* Other names: Xagrid;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Patients With Platelet Count ≤600x10^9/L After 12 Months | A platelet count of ≤600x10^9/L after 12 months is considered at least a partial response. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Patients With Platelet Count ≤400x10^9/L After 12 Months | A platelet count of ≤400x10^9/L after 12 months is considered a complete response. | 1 year | 
| Platelet Count |  | 1 year | 
| Red Blood Cell (RBC) Count |  | 1 year | 
| White Blood Cell (WBC) Count |  | 1 year | 
| Differential WBC Count - Neutrophils, Lymphocytes, Monocytes, and Basophils. |  | 1 year | 
| Differential WBC Count - Eosinophils |  | 1 year | 
| Hemoglobin Concentration |  | 1 year | 
| Hematocrit Level | The proportion of the volume of red blood cells to the total volume of blood. | 1 year |