Prophylactic management of severe Hemophilia A (HA) without inhibitors has historically relied on frequent intravenous infusions of standard or EHL FVIII concentrates or on subcutaneous emicizumab administered weekly to monthly intervals , yet both approaches maintain a notable treatment burden and variable factor utilization.
Efanesoctocog alfa (ALTUVOCT®, Swedish Orphan Biovitrum SOBI) was engineered as a fusion of FVIII, von Willebrand factor (VWF) binding domains, and XTEN polypeptides to decouple FVIII from endogenous VWF and extend its circulatory half-life beyond that of existing EHL concentrates.
In the pivotal XTEND-1 trial (NCT04161495) of 159 patients aged ≥ 12 years, once-weekly prophylaxis (50 IU/kg) yielded a mean ABR of 0.70 episodes per patient-year versus approximately 3.0 episodes on prior regimens. The study ended with superior bleeding protection, with FVIII activity above 40 IU/dL for the majority of each week and of 15 IU/dL at day 7. In children under 12, XTEND-Kids phase 3 data (n = 74) demonstrated comparable bleeding control; the average ABR for patients per year was 0.70. The XTEND-ed long-term extension (3-year data) assessed maintaining low ABRs, stable FVIII levels, and consistent tolerability. Efanesoctocog alfa was also well-tolerated in all trials, with adverse events similar to those of other FVIII products and no inhibitor development reported as a result of treatment. The analysis of pharmacokinetics indicated an extended half-life that supports once-weekly dosing and maintains FVIII activity in the normal to near-normal range (\> 40 IU/dL) for the majority of each dosing interval.
While regulatory and health-technology assessments recognize its favorable pharmacokinetics and hemostatic efficacy, they underscore the non-randomized, intra-patient design of these studies, the paucity of robust head-to-head comparisons with standard FVIII or emicizumab, and the absence of real-world QoL and consumption data. Despite the promising results, critical questions remain unanswered in routine clinical practice: efanesoctocog alfa is designed for once-weekly dosing but how does switching to efanesoctocog alfa alter real-world FVIII consumption, what clinical or psychosocial factors drive clinicians and patients to transition, and how do patients perceive efficacy, convenience, and treatment burden post-switch?
This study is designed to bridge this knowledge gap by quantifying pre- and post-switch FVIII utilization, systematically capturing switch-motivations through patient interviews, and applying validated patient-reported outcome measures to assess satisfaction and QoL impacts. Addressing these dimensions will not only inform personalized prophylaxis regimens and clarify resource utilization but also enrich pharmaco-economic models and guide future therapeutic innovations in HA management.
Individual profit - The switched patient must benefit from a lower injection frequency for the same clinical outcome (change of prescription); this could also favorably impact his quality of life. The possibility of changing the replacement therapy with FVIII or emicizumab to efanesoctocog alfa will be proposed to the patient during a routine consultation.
The Patient-Reported Outcome Measures (PROMs) will make it possible to properly appraise the patient's view. QoL questionnaires (PERQOLATEUR), Hemophilia Functional Ability Scoring Tool questionnaires (Hemo-FAST©) and treatment evaluation questionnaires will be presented (See Appendice 8), particularly during the shared decision-making consultation on the switch and the following routine consultation.
Group profit - This study will allow a better understanding of the use of health resources (quantification of FVIII consumption before and after switching to efanesoctocog alfa), to better understand the motivations of a person with HA to change treatment, and to evaluate in a real situation the impact on the patient's QoL of a new substitutive treatment.
The research has no risks and constraints because only questionnaires (part of routine care or without health data) are distributed to patients.
Conduct of research: patients followed up at one of the eight investigator centers of the BERHLINGO network
Pathology: severe HA (FVIII:C <1 IU/dL) or moderate HA (1 IU/dL < FVIII:C < 3 IU/dL), without inhibitor / with history of inhibitor (inhibitor rate < 0.6 Bethesda unit per milliliter (BU/mL))
Prophylactic Treatment with FVIII or emicizumab since at least March 1, 2025 -
Sex: male or female
Patients under guardianship
The study population targets people with severe hemophilia A or moderate hemophilia A (FVIII:C \< 3 IU/dL), without inhibitors / with history of inhibitors, of any sex, any age. These subjects must be followed in one centre of the BERHLINGO network. The patients will be included in the flow, with routine consultations.
Cohort
Prospective
Study questionnaires
Other interventionThe PERQOLATEUR project aims to develop a standardized yet personalized questionnaire to assess patients' perceived quality of life in relation to their condition and the treatments received. Patients are first asked to select the themes that matter most to them, and then to evaluate their well-being in relation to these themes, as well as the impact of their health problems and treatments on them. The questionnaire is particularly relevant for patients with chronic conditions, but well-being can be assessed in any individual (Co-development of the questionnaire with patients and healthcare professionals + Psychometric validation based on COSMIN recommendations + Item analysis using the Rasch model). The Hemo-FAST© questionnaire is a validated tool offering a quick and easy assessment of joint health and functionality by capturing both the adult patient and clinician perspectives, through the use of patient-reported-outcome and of physician-reported-outcome, with a score of 0 indic
Clinical/pharmacological data collection
Other interventionCollection of data from the patient's medical file on clinical evaluation and the patient's treatment history.
Description and comparison of the Hemophilia Functional Ability Scoring Tool questionnaires (Hemo-FAST©) before/after marketing authorization of ALTUVOCT® (efanesoctocog alfa) in adult people with severe or moderate hemophilia A (with FVIII:C < 3 IU/dL)
The Hemo-FAST© questionnaire is a validated tool offering a quick and easy assessment of joint health and functionality by capturing both the adult patient and clinician perspectives, through the use of patient-reported-outcome and of physician-reported-outcome, with a score of 0 indicating the best possible joint health status and a score of 100 as the worst.
Click on the lead sponsor to view all of their trials.
This trial is not recruiting at the moment. You can still explore other options:
