Unmet needs despite standard-of-care prophylaxis in hemophilia A: improved outcomes after switching to efanesoctocog alfa

@article{rauch2026unmet,
  title = {{Unmet needs despite standard-of-care prophylaxis in hemophilia A: improved outcomes after switching to efanesoctocog alfa}},
  author = {Antoine Rauch and Hortense Maynadié and Stéphanie Desage and Alexandra Fournel and Audrey Petit and Dominique Desprez and Valérie Proulle and Birgit Frotscher and Marie-Celeste Laroque and Sandrine Meunier and Yohann Repesse and Sophie Bayart and Sabine Castet and Brigitte Pan-Petesch and Valérie Roussel-Robert and Alexandre Theron and Marc Trossaert and Fabienne Volot and Valérie Chamouard and Laura Tourvielle and Claire Pouplard and Julien Labreuche and Mélanie Y. Daniel and Emmanuelle Jeanpierre and Sophie Susen and Yesim Dargaud and Roseline D’Oiron and Christophe Nougier},
  journal = {Blood Advances},
  year = {2026},
  month = jul,
  doi = {10.1182/bloodadvances.2026020401},
  url = {https://doi.org/10.1182/bloodadvances.2026020401},
  note = {CC BY-NC-ND 4.0},
}

TY  - JOUR
TI  - Unmet needs despite standard-of-care prophylaxis in hemophilia A: improved outcomes after switching to efanesoctocog alfa
AU  - Antoine Rauch
AU  - Hortense Maynadié
AU  - Stéphanie Desage
AU  - Alexandra Fournel
AU  - Audrey Petit
AU  - Dominique Desprez
AU  - Valérie Proulle
AU  - Birgit Frotscher
AU  - Marie-Celeste Laroque
AU  - Sandrine Meunier
AU  - Yohann Repesse
AU  - Sophie Bayart
AU  - Sabine Castet
AU  - Brigitte Pan-Petesch
AU  - Valérie Roussel-Robert
AU  - Alexandre Theron
AU  - Marc Trossaert
AU  - Fabienne Volot
AU  - Valérie Chamouard
AU  - Laura Tourvielle
AU  - Claire Pouplard
AU  - Julien Labreuche
AU  - Mélanie Y. Daniel
AU  - Emmanuelle Jeanpierre
AU  - Sophie Susen
AU  - Yesim Dargaud
AU  - Roseline D’Oiron
AU  - Christophe Nougier
PY  - 2026
DA  - 2026/07/16
JO  - Blood Advances
DO  - 10.1182/bloodadvances.2026020401
UR  - https://doi.org/10.1182/bloodadvances.2026020401
AB  - The Efanesoctocog Compassionate Hemophilia study (Méthodologie de Référence-004, number DEC24-269) provides a real-world evaluation of efanesoctocog alfa (efa), a first-in-class ultralong-acting factor VIII (FVIII) concentrate, within the French compassionate access authorization (CAA) framework. It aims to characterize the unmet medical needs leading to CAA requests and evaluate the hemostatic efficacy and biological monitoring of efa prophylaxis. This multicenter study included 50 patients with hemophilia A (84% severe; median age, 31 years), including 9 with inhibitor history. Although 54% of patients switched from FVIII prophylaxis, 46% of patients transitioned from emicizumab because of persistent breakthrough bleeding (88%) and complex multifactorial scenarios (76%). Over a median follow-up of 9 months, weekly efa prophylaxis resulted in a significant 89% reduction in treated bleeds (P < .001) and an 85% reduction in joint bleeds (P < .001) in the total population. This clinical benefit remained consistent across exploratory subgroups, including patients who were previously on emicizumab. No new-onset inhibitors occurred. Biologically, the median centralized day-7 trough level was 7 IU/dL using a drug-calibrated bovine chromogenic substrate assay (CSA, n = 31). However, a significant discrepancy was observed in paired comparisons (n = 18), where local 1-stage assays (OSAs) yielded a median trough level of 14 IU/dL, compared with a centralized CSA median of 7 IU/dL (P < .001). Notably, this divergence occurred across various local reagents considered acceptable alternatives to Actin FSL for efa monitoring. In conclusion, efa effectively addresses complex unmet needs, including those of emicizumab-treated patients. However, the discrepancy between results of local OSAs and drug-calibrated CSA highlights challenges in laboratory monitoring.
SN  - 2473-9529
SN  - 2473-9537
ER  -