An observational study in Haemophilia B and Haemophilia A, sponsored by Centre Hospitalier Universitaire de Saint Etienne. Completed at 1 site in France. Open to male participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2015-08-13.
Sponsored by Centre Hospitalier Universitaire de Saint Etienne · Observational
Personalized therapy in haemophilia has not been reached yet. Treatment is substitutive and its doses are only based on the levels of deficient factor VIII (for haemophilia A) or IX (for haemophilia B). The bleeding severity is not only related to the factor deficiency but also to levels of other coagulation factors (e.g. factor X, II, AT or TFPI). It's necessary to take them into account in order to individualize treatments; and Thrombin Generation Assay (TGA) with the CAT method (Calibrated Automated Thrombography) is a good way because it measures the result of the coagulation cascade. TGA on Platelet Rich Plasma (PRP) is even closer to physiological conditions than on Platelet Poor Plasma (PPP) because platelet influence is represented. It has already been shown (at least in PPP) that the bleeding tendency in haemophilic patients is usually well correlated to TG. Some TG parameters are used to characterize the individual coagulation phenotype, the most important being the Endogenous Thrombin Potential (ETP) and the Lag Time (LT). A hemorrhagic profile usually provides a longer lag time and / or a lower ETP. However, only few studies tried to determine the influence of each coagulation factor and inhibitor on TG. They were done on Platelet Poor Plasma (PPP) or on lyophilized plasma. So the relation between coagulation factors and the different TG parameters remains to be determined, especially in the haemophilic case. It is possible, experimentally, to find the optimal dose of the factor to be added by measuring TG in samples with different factor VIII or IX concentrations, but this method would be time consuming and expensive, especially because it should be done for each haemophilic patient. A better way consists in using TG numerical models. For a set of initial factor levels they simulate the TG and its associated parameters. It is now essential to validate the existing models, especially in haemophilic cases, in order to see whether they are reliable and can be used in clinical practice afterwards.The objective of this study is to validate thrombin generation numerical models which could predict the factor VIII or IX activity correction to reach a thrombin generation sufficient to avoid bleeding. A comparison between the TG observed in haemophilic patients and the TG predicted by the models is needed to validate the models. In order to define a 'safe' TG i.e. sufficient to avoid bleeding, normal ranges of TG parameters have to be measured.
866 studies on the registry are indexed under Hemophilia A; 137 are open to participants now.
This study's enrollment of 40 is below the median of 80 across 314 observational studies indexed under Hemophilia A.
Browse Hemophilia A studies →Centre Hospitalier Universitaire de Saint Etienne is the lead sponsor of 578 studies on the registry; 128 are open to participants now.
Counted across the registry records on this site, refreshed daily.
volunteers witch work in CHU Saint-Etienne
Exclusion Criteria:
Blood sampling : 1 blood punction of 36.5 ml for each volunteer
Other: blood sampling
Samplings will be taken on 4 citrated S-monovette tubes, 3 citrated tubes and 1 EDTA tube, namely 36.5 ml for each volunteer
Endogenous Thrombin Potential (ETP) predicted by numerical models
ETP (i.e. the aera under the thrombin generation curve, nM.min) measured in haemophilic patients is compared to ETP predicted by numerical models.
Time frame: up to 12 monthes
Lag Time of the thrombin generation curve predicted by numerical models
Lag time (min) measured in haemophilic patients is compared to the lag time predicted by numerical models
Time frame: up to 12 monthes
Peak value of the thrombin generation curve predicted by numerical models
Peak value (nmol thrombin) measured in haemophilic patients is compared to the peak value predicted by numerical models
Time frame: up to 12 monthes
Time to peak (TTP) of the thrombin generation curve predicted by numerical models
TTP (min) measured in haemophilic patients is compared to TTP predicted by numerical models
Time frame: up to 12 monthes
Velocity Index (V) of the thrombin generation curve predicted by numerical models
Velocity Index measured in haemophilic patients is compared to TTP predicted by numerical models
Time frame: up to 12 monthes
Endogenous Thrombin Potential (ETP) for volunteers
ETP (i.e. the aera under the thrombin generation curve, nM.min) is measured by Thromboplastin Generation Tests (TGTs)
Time frame: day 1
Lag Time of the thrombin generation curve for volunteers
Lag time (min) of the thrombin generation curve is measured by Thromboplastin Generation Tests (TGTs)
Time frame: day 1
Peak value of the thrombin generation curve for volunteers
Peak value of the thrombin generation curve is measured by Thromboplastin Generation Tests (TGTs)
Time frame: day 1
Time to peak (TTP) of the thrombin generation curve for volunteers
TTP of the thrombin generation curve is measured by Thromboplastin Generation Tests (TGTs)
Time frame: day 1
Velocity Index (V) of the thrombin generation curve for volunteers
Velocity Index (V) of the thrombin generation curves measured by Thromboplastin Generation Tests (TGTs)
Time frame: day 1
This study is completed, as verified in Aug 2015. You cannot join it, but the record below documents what was studied.
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Centre Hospitalier Universitaire de Saint Etienne