Polycythemia Vera, Thrombocythemia, Essential
Conditions
Brief summary
Myeloproliferative neoplasms (MPN) such as Polycythemia Vera (PV) and, Essential Thrombocythaemia (ET) are rare clonal myeloid neoplasms associated with an increased risk of both venous and arterial thrombosis. Thrombotic complications are the main determinant of morbidity and in a less extend mortality. Routine haemostasis analysis (TP, aPTT) are usually normal and are useless to demonstrate a hypercoagulable state. However, previous evidence suggests that global coagulation tests such as thrombin generation or thromboelastometry are able to detect signs of procoagulant imbalance in MPN. Similarly, current data seems to demonstrate that fibrin clot properties (clot permeability, turbidimetry, clot lysis time) properties is altered suggesting an hypercoagulable state. Goals of PV and ET treatments are to control blood count to reduce the risk of thrombotic events. Moreover, new drugs such as Janus Kinase Inhibitors (JAKi) were recently licensed for PV and are under investigations on clinical trial for ET. It is currently unknown if treatments that were used for ET and PV, and especially JAKi are able to modify the hypercoagulable state that is observed in those diseases, and if there is difference between drugs. To evaluate impact of MPN treatment on prothrombotic haemostatic profile, we propose to evaluate global coagulation and fibrin clot properties in MPN, depending on the treatment.
Interventions
DRUGNo cytoreductive vs cytoreductive drugs
No cytoreductive treatment vs cytoreductive drugs (hydroxycarbamide, alpha-interferon, ruxolitinib).
Sponsors
Dr Yan Beauverd
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* All men and women, older than 18 years, with a diagnosis of PV or ET (primary or secondary) according to the 2008 World Health Organization (WHO) classification.
Exclusion criteria
* Lack of participant's consent; * Concomitant treatment with anticoagulant drugs (anti-vitamin K, heparin or direct oral anticoagulant drugs); * Active cancer other than non-melanoma skin cancer (defined as cancer diagnosis \<5 years or treatment \<2 years); * Recent infection (\<30d); * Recent surgery (\<30d); * Recent hospitalization (\<30d); * Recent thromboembolic or cardiovascular event (\<3m).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Fibrin polymerization; lag-time (in seconds) | At time of inclusion | Fibrin polymerization will be assessed by turbidity assay on plasma. Fibrin polymerization will be monitored at 340 nm after incubation with human thrombin and CaCl2. Results will report lag-time (seconds). |
| Fibrin polymerization; maximal absorbance | At time of inclusion | Fibrin polymerization will be assessed by turbidity assay on plasma. Fibrin polymerization will be monitored at 340 nm after incubation with human thrombin and CaCl2. Results will report maximal absorbance. |
| Clot lysis time (in minutes) | At time of inclusion | Fibrinolysis will be assessed by turbidity assay on plasma. Fibrinolysis will be monitored by adding tissue plasminogen activator (tPA). Results will report clot lysis time (minutes) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Quantitative parameters of thrombin generation test (TGT); time to peak (minutes) | At time of inclusion | The measurement of thrombin generation is performed by the technique calibrated automated thrombogram (CAT). Time to peak will be reported in minutes. |
| Clot permeation; permeation coefficient | At time of inclusion | Clot permeation will be reported as the calculated permeation coefficient (Ks). |
| Fibrin density by laser scanner confocal microscopy (number per 100 μm) | At time of inclusion | The fibrin density was determined by counting the number of fibres crossing an arbitrary line of 100 μm drawn through a single optical section. Each fibrin clot is prepared in duplicate and 20 density measurements were performed on each sample. |
| Quantitative parameters of thrombin generation test (TGT); endogenous thrombin potential (nM*minutes) | At time of inclusion | The measurement of thrombin generation is performed by the technique of calibrated automated thrombogram (CAT). Endogenous thrombin potential will be reported in nM\*minutes. |
| Quantitative parameters of thrombin generation test (TGT); peak (nM) | At time of inclusion | The measurement of thrombin generation is performed by the technique of calibrated automated thrombogram (CAT). Peak will be reported in nM. |
Countries
Switzerland, United Kingdom
Outcome results
None listed