Case Reports
Vol. 5 No. 2 (2026)
https://doi.org/10.4081/btvb.2026.467

Efficacy, safety and surgical management with concizumab prophylaxis in three young patients affected by severe hemophilia with inhibitors

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Published: 11 May 2026
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Anti-TFP, efficacy, hemophilia, inhibitors, safety, surgery

Authors

Silvia Linari
linaris@aou-careggi.toscana.it
https://orcid.org/0000-0002-5849-7377
Center for Bleeding Disorders and Coagulation, Careggi University Hospital, Florence, Italy.
Lisa Pieri
Center for Bleeding Disorders and Coagulation, Careggi University Hospital, Florence, Italy.
Raffaella Pasquino
Center for Bleeding Disorders and Coagulation, Careggi University Hospital, Florence, Italy.
Eleonora Piellucci
Center for Bleeding Disorders and Coagulation, Careggi University Hospital, Florence, Italy.
Monica Attanasio
Center for Bleeding Disorders and Coagulation, Careggi University Hospital, Florence, Italy.
Francesca Salvianti
Center for Bleeding Disorders and Coagulation, Careggi University Hospital, Florence, Italy.
Giancarlo Castaman
Center for Bleeding Disorders and Coagulation, Careggi University Hospital, Florence, Italy.

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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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 Oct. 23];5(2). Available from: https://www.btvb.org/btvb/article/view/467
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