Clinical trial NCT02061033: Global Hemostatic Methods in Hemophilia and Von Willebrand's Disease
Official title: GLOBAL HEMOSTATIC METHODS IN HEMOPHILIA AND VON WILLEBRAND'S DISEASE CORRELATION WITH PATIENTS' CLINICAL STATUS AND USEFULNESS FOR TREATMENT MONITORING
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Hemophilia A
Hemophilia B
Von Willebrand's Disease
Keywords: Hemophilia A
Hemophilia B
Von Willebrand's Disease
Endogen thrombin potential
Overall hemostatic potential
Microparticles
Fibrin clot
Lead sponsor: Karolinska University Hospital
Sponsor class: OTHER
Collaborators: name: The Swedish Society of Medicine
name: Karolinska Institutet
First posted: 2014-02-12
Enrollment: 180
Sex: ALL
Minimum age (years): 10
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: 100 patients with moderate and severe hA, 30 patients with moderate and severe hB and 50 patients with VWD (primarily severe type I and type III) from hemophilia centers Stockholm, Sweden and Belgrade, Serbia.

Brief summary: Patients with hemophilia who have the same level of deficient factor(s) may express different severity of clinical presentation and bleeding tendency. Therefore a test which could determine overall hemostasis rather than simple concentration of a single deficient factor may correlate better with clinical phenotype in these patients.

The investigators will therefore study the usefulness of global hemostatic methods (endogenous thrombin potential (ETP), overall hemostatic potential (OHP), fibrin clot structure) and microparticles in the prediction of severity of bleeding and estimation of response to the treatment in patients with hemophilia.

Since hemophilia patients on prophylactic treatment virtually do not bleed, additional patients who are treated on demand only will be included enabling to study possible modulatory effects of different hemostatic factors (particularly prothrombotic and thrombin activatable fibrinolysis inhibitor (TAFI)) on clinical presentation. The investigators will correlate both those factors and clinical severity with global hemostatic methods.

The investigators expect to prove that individual tailoring of the treatment, which may enable lowering the prophylactic dose of factor concentrate without increasing the risk of bleeding, is justified in some hemophilia patients. This approach would reduce the amount of necessary factor concentrate in certain patients and decrease the cost (which represents extensive burden for health care systems) of treatment without potential risk for the patients.


Eligibility criteria: Inclusion Criteria:

* patients with bleeding disorders

Exclusion Criteria:

* none

Primary outcomes:
measure: Number of microparticles
timeFrame: 5 years
Secondary outcomes:
Other outcomes:
Locations:
city: Stockholm
country: Sweden
facility: Karolinska University Hospital
Study officials:
References:
citation: Antovic JP, Mikovic D, Elezovic I, Holmstrom M, Wilkens M, Elfvinge P, Mahmoud Hourani Soutari N, Antovic A. Two global haemostatic assays as additional tools to monitor treatment in cases of haemophilia A. Thromb Haemost. 2012 Jul;108(1):21-31. doi: 10.1160/TH11-11-0811. Epub 2012 Apr 26.
citation: Mobarrez F, Mikovic D, Antovic A, Antovic JP. Is a decrease of microparticles related to improvement of hemostasis after FVIII injection in hemophilia A patients treated on demand? J Thromb Haemost. 2013 Apr;11(4):697-703. doi: 10.1111/jth.12103.