Clinical trial NCT05217992: Are There Differences Between Carriers of Haemophilia A and B?
Official title: Are There Differences Between Carriers of Haemophilia A and B? A Comparative Study of Clotting Factor Deficiencies, Bleeding Phenotype and Haemostatic Treatment Requirements
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Hemophilia
Keywords: hemophilia A
hemophilia B
genetic testing
carriers
Lead sponsor: Cliniques universitaires Saint-Luc- Université Catholique de Louvain
Sponsor class: OTHER
First posted: 2022-02-01
Enrollment: 900
Sex: FEMALE
Minimum age (years): 12
Maximum age (years): 85
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: FAMILY_BASED
Time perspective: PROSPECTIVE
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.

Brief summary: 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).

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.

Eligibility criteria: Inclusion Criteria:

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

Exclusion Criteria:

* None.

Primary outcomes:
measure: Number of carriers, bleeding phenotype in hemophilia A and B carriers
timeFrame: 18 month
Secondary outcomes:
Other outcomes:
Locations:
city: Bruxelles
country: Belgium
facility: Cliniques universitaires Saint-Luc
state: International
Study officials:
affiliation: Cliniques universitaires Saint-Luc- Université Catholique de Louvain
name: Cedric Hermans, MD,PhD
role: PRINCIPAL_INVESTIGATOR
References: