News|Articles|September 21, 2026

When Innovation Builds Clinical Confidence: Evaluating Treatment Options in Hemophilia A

Content sponsored by Sanofi

As treatment options for hemophilia A expand, selecting prophylaxis is becoming more complex, not because clinicians have fewer effective options, but because available therapies may differ in important ways beyond how they are administered or how frequently they are given.¹

These differences create greater opportunities to individualize care around each patient’s clinical needs, lifestyle and treatment goals. They also require clinicians to consider how a therapy works, how its activity is measured or characterized, the depth of evidence supporting its use and the role it may play across a broader care plan.¹

Administration method and dosing frequency are meaningful considerations. They may affect treatment burden, adherence and patient preference.^1,2However, as treatment options diversify, clinicians may also consider what lies beyond these individual attributes: how a therapy works, what its clinical evidence demonstrates, the depth of that clinical evidence and how it can be used when care extends beyond the routine prophylaxis schedule.¹

Together, these considerations form a more complete treatment profile—one that can help HCPs evaluate how the full body of evidence aligns with the individual patient.¹

Considering Different Mechanisms in Treatment Selection

Hemophilia A is characterized by deficient or dysfunctional factor VIII. Available therapies address this underlying hemostatic challenge through different biological approaches, including replacing the missing factor or supporting coagulation through another mechanism.¹

These differences may influence how clinicians characterize treatment activity and plan care across a range of clinical situations. Factor VIII replacement, for example, increases measurable plasma factor VIII activity, providing a familiar clinical measure that can help inform discussions about the dosing interval.¹

For clinicians, this measurable activity can help inform treatment discussions involving individual goals, planned activities, bleeding episodes or procedures.¹ Mechanisms are one component of a broader treatment assessment. Its clinical relevance becomes clearer when considered alongside efficacy, safety, administration, the depth of supporting evidence and the therapy’s role across the care journey.¹

ALTUVIIIO® [antihemophilic factor (recombinant), Fc-VWF-XTEN fusion protein-ehtl]: Factor VIII replacement designed for higher, sustained activity

These broader considerations become more meaningful when viewed through the profile of an individual therapy.

ALTUVIIIO® [antihemophilic factor (recombinant), Fc-VWF-XTEN fusion protein-ehtl], is the first and only ultra-long half life (UHL) factor replacement therapy with once-weekly prophylactic dosing for adults and children with hemophilia A.³ As with other factor VIII therapies, ALTUVIIIO carries a risk of hypersensitivity reactions and inhibitor development. The most common adverse reactions reported in clinical studies were headache and arthralgia.³

ALTUVIIIO temporarily replaces the factor VIII needed for effective hemostasis and increases measurable plasma factor VIII activity. It was designed to extend factor VIII activity beyond the limitations of earlier factor VIII therapies, supporting higher, sustained activity with once-weekly routine prophylaxis.³

At steady state, adults receiving once-weekly ALTUVIIIO maintained factor VIII activity above 40 IU/dL for a mean of 4.1 days after administration. In children younger than 12 years, activity above 40 IU/dL was maintained for approximately 2 to 3 days, while activity above 10 IU/dL was maintained for approximately 7 days.³

This sustained, measurable factor activity is supported by clinical evidence across adults, adolescents and children.

Established Evidence Across Age Groups

The ALTUVIIIO development program evaluated that relationship across age groups, bleeding outcomes and joint health.

In XTEND-1, the phase 3 study in adults and adolescents with severe hemophilia A, 128 patients receiving once-weekly ALTUVIIIO prophylaxis achieved a mean annualized bleeding rate for treated bleeds of 0.70 (95% CI, 0.5–1.0) and a median ABR of 0.0 (Q1, Q3: 0.0, 1.0). During the 52-week prophylaxis period, 64.1% of patients, or 82 of 128, experienced zero treated bleeds.³

Among patients included in an intrapatient comparison, ALTUVIIIO reduced mean ABR by 77% compared with prior factor VIII prophylaxis (95% CI, 58%–87%).³

The evidence also extended beyond overall bleed rates. All 45 participants with target joints at baseline met the study definition for target-joint resolution after 12 months of once-weekly prophylaxis.³

Findings from XTEND-Kids, the phase 3 study in children younger than 12 years with severe hemophilia A, were consistent with the broader clinical profile. Among 72 children receiving once-weekly prophylaxis, the mean ABR for treated bleeds was 0.6 (95% CI, 0.4–0.9), and 64%, or 46 of 72, experienced zero treated bleeds during the 52-week treatment period.³

No factor VIII inhibitors were detected in XTEND-1 or XTEND-Kids.^4,5 However, inhibitor development is a known risk of factor VIII replacement therapy, and neutralizing anti-factor VIII antibodies have been reported following ALTUVIIIO administration in the postmarketing setting.³

Together, these findings contribute to an established and growing body of evidence across adults and children. This depth of evidence can be particularly reassuring as clinicians evaluate therapies that differ not only in their administration or dosing frequency, but also in how extensively their performance has been characterized across populations and clinical settings.

Looking Beyond the Routine Prophylaxis Schedule

A complete treatment profile must also account for the moments that fall outside the planned weekly schedule.

Routine prophylaxis is central to hemophilia management, but it is not the only situation clinicians and patients must plan for. Injuries occur. Breakthrough bleeds may require treatment. Dental work and surgical procedures can create additional hemostatic needs.¹

In these moments, the question extends beyond whether a therapy provides protection during routine prophylaxis. Clinicians must also understand how it can be used when the care plan changes.

ALTUVIIIO is approved for routine prophylaxis, on-demand treatment and control of bleeding episodes, and perioperative management of bleeding in adults and children with hemophilia A.³

Across the clinical program, nearly all treated bleeding episodes were resolved with one injection of ALTUVIIIO: 97% in XTEND-1 and 95% in XTEND-Kids.^4,5 Clinical studies also evaluated ALTUVIIIO for perioperative management, supporting its approved role in surgical settings.³

This breadth allows clinicians to consider routine prophylaxis, treatment of bleeding episodes and perioperative planning within one approved factor replacement profile. It also reflects the realities of hemophilia care, in which treatment planning must address both the expected routine and the situations that may arise unexpectedly.

Supporting Individualized Treatment Decisions

No single treatment attribute will carry the same importance for every person with hemophilia A.

Administration method and dosing frequency may be central for one patient, while measurable factor activity, joint history, management of bleeding episodes or plans for surgery may carry greater weight for another. Age, inhibitor status, venous access, treatment experience and personal goals may also shape the conversation.^1,2

As treatment options continue to expand, clinicians are increasingly evaluating therapies through their complete treatment profile rather than any single attribute. Administration method and dosing frequency remain important considerations, alongside mechanism of action, measurable factor VIII activity, the maturity of the supporting evidence and how a therapy can support patients across the full spectrum of hemophilia care.¹

Viewed through that broader framework, ALTUVIIIO offers a factor VIII replacement profile supported by higher, sustained factor VIII activity with once-weekly routine prophylaxis, established clinical evidence across age groups and approved use in routine prophylaxis, on-demand treatment and perioperative management.³ Collectively, these attributes can help inform individualized treatment decisions aligned with each patient’s clinical needs and treatment goals.

ALTUVIIIO Indication and Important Safety Information

INDICATION:

ALTUVIIIO® [antihemophilic factor (recombinant), Fc-VWF-XTEN fusion protein-ehtl] is a recombinant DNA-derived, Factor VIII concentrate indicated for use in adults and pediatric patients with Hemophilia A (congenital factor VIII deficiency) for:

Routine prophylaxis to reduce the frequency of bleeding episodes
On-demand treatment and control of bleeding episodes
Perioperative management of bleeding

LIMITATION OF USE:

ALTUVIIIO is not indicated for the treatment of von Willebrand disease.

IMPORTANT SAFETY INFORMATION

CONTRAINDICATIONS

ALTUVIIIO is contraindicated in patients who have had severe hypersensitivity reactions, including anaphylaxis, to the product or its excipients.

WARNINGS AND PRECAUTIONS

Allergic-type hypersensitivity reactions, including anaphylaxis, have occurred with ALTUVIIIO. Discontinue use of ALTUVIIIO if hypersensitivity reaction occurs and manage symptoms as appropriate.
Formation of neutralizing antibodies (inhibitors) to Factor VIII has been reported following administration of ALTUVIIIO. Monitor all patients for the development of Factor VIII inhibitors by appropriate clinical observations and laboratory tests.
If assessment of plasma Factor VIII activity is needed, it is recommended to use a validated one-stage clotting assay. The ALTUVIIIO Factor VIII activity level is overestimated by the chromogenic assay and a specific ellagic acid-based aPTT reagent in one-stage clotting assay by approximately 2.5-fold. If these assays are used, divide the result by 2.5 to approximate the patient’s ALTUVIIIO Factor VIII activity level.

ADVERSE REACTIONS:

The most common adverse reactions (>10% of subjects) reported in clinical trials were headache and arthralgia.

Please see Full Prescribing Information

For more information about ALTUVIIIO visit www.altuviiio.com

References

Srivastava A, Santagostino E, Dougall A, et al. WFH guidelines for the management of hemophilia, 3rd edition. Haemophilia. 2020;26(suppl 6):1-158.
Thornburg CD, Duncan NA. Treatment adherence in hemophilia. Patient Prefer Adherence. 2017;11:1677-1686. Veeva ID: REF-22777.
ALTUVIIIO® Prescribing information. Sanofi; 2025. Accessed August 6, 2026.
von Drygalski A, Chowdary P, Chamberlin S, et al. Efanesoctocog alfa prophylaxis in adults and adolescents with severe haemophilia A. N Engl J Med. 2023;388(4):310-318. Veeva ID: REF-217939.
Malec LM, et al. Efanesoctocog alfa prophylaxis for hemophilia A. N Engl J Med. 2024;391(3):235-246. Veeva ID: REF-292760.