Related Experiment Video
Updated: Nov 21, 2025

Cortical Bone Assessment Using Ultrasonic Guided Waves: A Reproducibility Study in a Healthy Population
Published on: January 31, 2025
PHILEOS (haemoPHILia and ostEoporOSis) Study: protocol of a multicentre prospective case-control study
Brigitte Tardy-Poncet1,2,3, Barbara Play4, Aurélie Montmartin3
1Inserm CIC 1408, Saint-Etienne University Hospital Center, Saint-Etienne, Rhône-Alpes, France brigitte.tardy@chu-st-etienne.fr.
Introduction:
Two meta-analyses showed lower bone mineral density (BMD) in patients with haemophilia (haemophilia type and severity were often not specified) compared with healthy controls. This finding could be related to reduced mobility and sedentary lifestyle, and/or hepatitis C or HIV infection. The aim of this study is to determine osteoporosis prevalence in patients with haemophilia classified in function of the disease type (A or B) and severity, and to evaluate the potential role of regular prophylactic factor replacement (early vs delayed initiation) in preserving or restoring BMD.
Methods And Analysis:
The haemoPHILia and ostEoporOSis Study is a prospective, controlled, multicentre study that will include patients in France (13 haemophilia treatment centres), Belgium (1 centre) and Romania (1 centre). In total, 240 patients with haemophilia and 240 matched healthy controls will be recruited (1:1). The primary objective is to determine osteoporosis prevalence in patients with severe haemophilia A and B (HA and HB) without prophylaxis, compared with healthy controls. Secondary outcomes include: prevalence of osteoporosis and osteopenia in patients with mild, moderate and severe HA or HB with prophylaxis (grouped in function of their age at prophylaxis initiation), compared with healthy subjects; BMD in patients with HA and HB of comparable severity; correlation between BMD and basal factor VIII/IX levels and thrombin potential; and quantification of plasmatic markers of bone remodelling (formation and resorption) in patients with haemophilia.
Ethics And Dissemination:
The protocol was approved by the French Ethics Committee and by the French National Agency for Medicines and Health Products Safety (number: 2019-A03358-49). The results of this study will be actively disseminated through scientific publications and conference presentations.
Trial Registration Number:
NCT04384341.
Related Concept Videos
Study Designs in Epidemiology
Observational studies are those where the researcher does not intervene but rather observes natural variations. They include cross-sectional, cohort, and...
Genome-wide Association Studies-GWAS
GWAS does not require the identification of the target gene involved in...
Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...
Bioavailability Study Design: Healthy Subjects Versus Patients
Bone Remodeling