Are There Differences Between Carriers of Haemophilia A and B?

Are There Differences Between Carriers of Haemophilia A and B? A Comparative Study of Clotting Factor Deficiencies, Bleeding Phenotype and Haemostatic Treatment Requirements

This study aims to develop a systematic genetic screening strategy for (potential) female carriers of haemophilia by identifying as many female carriers as possible within the families of haemophilia patients regularly followed at Cliniques universitaires Saint-Luc (CUSL) and to search for differences between female carriers of haemophilia A (HA) and B (HB).

Study Overview

• Status: Completed
• Conditions: Hemophilia
• Intervention / Treatment: Other: Genetic assessment (hemophilia testing)

Detailed Description

In order to complete our local registry of female carriers, the family trees of haemophilia patients will be systematically updated during their follow-up consultations at the haemophilia centre. Female carriers not yet known in our centre, identified by the updating of pedigrees, will be invited to present themselves in the haematology consultation and to participate in the study by means of an invitation and information letter which will be given/sent to them by the index haemophilia patient. Female carriers already known for whom missing data and/or the indication of regular follow-up have been identified during the file review will also be invited to attend a consultation within the framework of the study.

At these consultations, (potential) carriers will be given information about haemophilia, the mode of genetic transmission and the implications of carrier status on patients' lives (bleeding prevention, reproductive choices, current haemophilia treatments and future prospects). We will then determine the bleeding phenotype of each patient by taking a comprehensive bleeding history. With the consent of the participants concerned, the familial genetic variant responsible for haemophilia will be sought in them in order to definitively establish their carrier status. The basal level of coagulation factors VIII (HA)/IX (HB) will also be determined. If a deficiency is found, haemostatic treatment adapted to the patient's situation will be initiated and clinical follow-up outside the study recommended.

After completion of the data collection, the data will be analyzed and compared between HA and HB carriers in order to identify possible differences between these two populations.

• Study Type: Observational
• Enrollment (Actual): 900

Contacts and Locations

Study Locations

• Belgium
  • International
    • Bruxelles, International, Belgium, 1200
      • Cliniques Universitaires Saint-luc

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 12 years to 85 years (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

1. Carriers of HA/HB already known and registered at the HTC (i.e. with an EMR).
2. Carriers identified by pedigree review, invited/informed by family related haemophilia patients registered in the HTC, accepting to participate after informed consent.

Description

Inclusion Criteria:

- Family member affected by haemophilia A or B and potential/obligate carriership of HA/HB.

Exclusion Criteria:

• None.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Carriers or potential carriers of hemophilia A and B; All obligate and potential carriers among families of patient with hemophilia followed at the hemophilia treatment center of the Cliniques universitaires Saint-Luc, Brussels. Belgium	Other: Genetic assessment (hemophilia testing); Determination of carrier ship of hemophilia with molecular tests

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of carriers, bleeding phenotype in hemophilia A and B carriers	Comparison of bleeding phenotype between hemophilia A and B carriers, number of carriers per family confirmed at the end of the study	18 month

Collaborators and Investigators

• Sponsor: Cliniques universitaires Saint-Luc- Université Catholique de Louvain
• Investigators: Principal Investigator: Cedric Hermans, MD,PhD, Cliniques Universitaires Saint-luc

Study record dates

Study Major Dates

• Study Start (Actual): May 25, 2021
• Primary Completion (Actual): April 30, 2023
• Study Completion (Actual): April 30, 2023

Study Registration Dates

• First Submitted: January 19, 2022
• First Submitted That Met QC Criteria: January 19, 2022
• First Posted (Actual): February 1, 2022

Study Record Updates

• Last Update Posted (Actual): August 7, 2023
• Last Update Submitted That Met QC Criteria: August 4, 2023
• Last Verified: August 1, 2023

More Information

Terms related to this study

• Keywords: genetic testing; hemophilia A; carriers; hemophilia B
• Additional Relevant MeSH Terms: Hematologic Diseases; Blood Coagulation Disorders, Inherited; Coagulation Protein Disorders; Hemorrhagic Disorders; Genetic Diseases, Inborn; Blood Coagulation Disorders; Hemophilia A
• Other Study ID Numbers: 2021/29MAR/153

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No