Skip to content

Platelet Function in Patients With Hemophilia A

Decreased Platelet Function as a Cause of Increased Bleeding in Patients With Hemophilia A

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT02093065
Enrollment
36
Registered
2014-03-20
Start date
2015-03-31
Completion date
2020-02-01
Last updated
2020-07-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hemophilia A

Keywords

severe hemophilia A, coated platelets, bleeding

Brief summary

Abnormalities in the gene encoding Factor VIII (FVIII) results in hemophilia A, an X-linked recessive bleeding disorder with a prevalence of 1 in 5000 males. Hemophilia A patients are classified into 3 different categories based on residual FVIII activity compared to normal: mild (6-40%), moderate (1-5%) and severe (\<1%). This categorization correlates to some degree with bleeding phenotype, but does not completely define it. Some patients with hemophilia A bleed less often than others despite identical plasma FVIII levels. The cause(s) of this phenotype heterogeneity in hemophilia A remains largely unknown, despite a number of studies of possible factors. Activated platelets, in addition to their role in primary hemostasis, play a major role in secondary hemostasis (coagulation) by providing a phospholipid surface to which coagulation factors bind. A role for platelets in the hemorrhagic propensity of hemophilia A has been suggested in the past, but only a small number of studies have been performed with limitations in assays performed and numbers of patients. The purpose of the present study is to determine whether platelet reactivity in severe hemophilia A patients is associated with past bleeding frequency and/or predicts future bleeding frequency.

Interventions

None listed

Sponsors

Baxter Healthcare Corporation
CollaboratorINDUSTRY
Boston Children's Hospital
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
MALE
Age
2 Years to 18 Years
Healthy volunteers
No

Inclusion criteria

* Patients with severe hemophilia A who are being prophylactically treated with FVIII. * Age of at least 2 years. * Bleeding history of at least 6 months. * IRB-approved informed consent.

Exclusion criteria

* Presence of FVIII inhibitors. * Greater than 7 days since active bleeding.

Design outcomes

Primary

MeasureTime frame
The percentage of coated platelets.2 years

Secondary

MeasureTime frame
Platelet reactivity.2 years
The number of procoagulant platelet-derived microparticles.2 years

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026