Case Reports
Vol. 5 No. 2 (2026)
Efficacy, safety and surgical management with concizumab prophylaxis in three young patients affected by severe hemophilia with inhibitors
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All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.
Published: 11 May 2026
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Background: concizumab is an anti-tissue factor inhibitor monoclonal antibody designed as a once-daily subcutaneous prophylactic treatment for all hemophilia patients. The efficacy and safety of concizumab have been documented in the Explorer research program.
Objectives: we describe the management and clinical outcomes of 3 subjects treated with concizumab in the phase 3 Explorer 7 trial, in which patients with hemophilia A/B with inhibitors (HAPwI/HBPwI) were enrolled.
Methods: in 3 subjects (1 HAPwI and 2 HBPwI) followed in our Centre and enrolled in Explorer 7 trial the following data were collected: diagnosis, age at switch to concizumab, pre-switch antihemorrhagic treatment, venous access, joint involvement, bleeding events in the 6 months before switch, comorbidity, medications, quality of life (QoL), physical activity, date of switch and following bleeding events, treatment with recombinant activated factor VII (rFVIIa), surgery, QoL, physical activity.
Results: during the 5 years following the switch to concizumab all the patients had a drastic reduction in bleeding events and therefore of treatment with rFVIIa. A significant improvement in QoL, both in relation to pain reduction, movement ability and autonomy from caregivers, was achieved. No side effects were observed, and the management of 1 major and 14 minor surgeries did not present any bleeding or thrombotic complications.
Conclusions: concizumab represents a unique opportunity for HBPwI, but it may be of extreme value also for HAPwI. In our cases concizumab demonstrates and confirms clinical efficacy, positive impact on QoL and safety even in surgical settings.
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Citations
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Ethics Approval
the Explorer 7 trial was approved by the Ethical Committee of Careggi University Hospital in Florence and patients signed informed consent for participation.CRediT authorship contribution
SL analyzed and interpreted the data and wrote the manuscript. GC analyzed and interpreted the data and revised the manuscript. LP, RP, EP, MA, and FS were involved in the management of patients. All authors reviewed and approved the final version of the manuscript
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
How to Cite
1.
Linari S, Pieri L, Pasquino R, Piellucci E, Attanasio M, Salvianti F, et al. Efficacy, safety and surgical management with concizumab prophylaxis in three young patients affected by severe hemophilia with inhibitors. Bleeding Thromb Vasc Biol [Internet]. 2026 May 11 [cited 2026 May 12];5(2). Available from: https://www.btvb.org/btvb/article/view/467
Copyright (c) 2026 The Author(s)
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
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