Hemophilia
Conditions
Keywords
anti-TFPI antibody, thrombin generation, tissue factor concentration
Brief summary
Studies have shown, in haemophilia patients, the effectiveness of Anti TFPI antibody (aTFPIAb) to prevent joint and muscular bleeding (tissues poor in Tissue Factor (TF)). However, cases of cerebral thrombosis (tissues rich in TF) have been observed in some patients treated with this antibody. Because an inter-individual variation in thrombin generation correction by aTFPIAb, an aTFPIAb concentration effective at low TF concentration could be at the same time thrombogenic at high TF concentration.
Detailed description
The aim of this study is to determine, for each patient, the minimum concentration of aTFPIAb necessary to restore thrombin generation in the presence of low (1pM) TF concentration and to evaluate at this concentration of aTFPIAb a potential thrombogenic effect in the presence of a high (10pM) TF concentration.
Interventions
OTHERthrombin generation measurement
Thrombin generation will be measured in Platelets rich plasma induced either by 1 pM TF or 10 pM TF concentration in presence of different aTFPIAb concentrations (0; 0.5 µg/ml; 0.75 µg/ml; 1.0 µg/ml; 2.0 µg/ml; 4.0 µg/ml)
Sponsors
Centre Hospitalier Universitaire de Saint Etienne
Study design
Observational model
OTHER
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
MALE
Age
12 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Severe or moderate haemophilia A or B patient with FVIII or FIX \<5% with or without prophylaxis * Affiliated or beneficiary of a social security regimen * Signature of consent
Exclusion criteria
* Haemophilia patients aged 12 years or less with a weight less than 30 kg (taking into account the volume of blood collection). * Patients who received factor VIII concentrates less than 48 hours or factor IX concentrates less than 96 hours prior to the routine blood draw at the Hemophilia Clinic. 96 hours prior to the routine blood draw at the Hemophilia Centre
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| minimum concentration of anti-TFPI antibody | day 1 | Determine the minimum concentration of anti-TFPI antibody (µg/ml) that normalizes the peak to 1 pM FT |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Measurement of the clot structure | day 1 | Measurement of the clot structure (density fibers in g/cm3) by scanning electron microscopy |
Countries
France
Outcome results
None listed