An observational study in Hemophilia A, sponsored by Emory University. Recruiting at 2 sites in 2 countries. Open to male participants. Per ClinicalTrials.gov, last updated 2026-09-23.
Sponsored by Emory University · Observational
This is a non-interventional, multicenter, observational, international study in male persons with haemophilia A who have developed inhibitors to any replacement coagulation factor VIII (FVIII) product. The purpose of the study is to capture different approaches in the management of persons with haemophilia A and FVIII inhibitors, document current immune tolerance induction approaches, and evaluate the efficacy and safety of immune tolerance induction, including the combination of FVIII and emicizumab. Patients will be assigned to 1 of 3 groups based on the treatments they receive, and may switch to another group if their treatment is changed. Participants will be followed after a maximum observational period of 5 years.
This study will capture different approaches in the management of persons with haemophilia A (HA) and inhibitors. HA is a serious blood coagulation disorder caused by a deficiency in FVIII that results in a failure to produce FVIII in sufficient quantities to achieve satisfactory haemostasis. Patients with HA are predisposed to recurrent bleeds into joints and soft tissues that culminate in debilitating arthropathy and long-term morbidity. HA can be effectively treated with replacement FVIII concentrates, obtained by fractionation of human plasma (pdFVIII) or using recombinant technology (rFVIII). In patients receiving FVIII replacement therapy, inhibitors can develop that neutralise the effect of treatment. Inhibitors develop in \~35% of patients who have not been previously exposed to FVIII treatment and \~1% of patients who have undergone previous FVIII treatment. Inhibitor development has major adverse implications on bleeding rates, morbidity, mortality and quality of life.
Immune tolerance induction (ITI), which involves prolonged treatment with plasma-derived (pdFVIII) or recombinant FVIII (rFVIII), is the only clinically proven strategy for eradication of inhibitors and is recommended as the primary treatment option in European and US guidelines. Bypassing agents (activated recombinant factor VII [rFVIIa] and activated prothrombin complex concentrate [aPCC]) are used to manage bleeding episodes (BEs) and for prophylaxis or in surgical settings in patients with FVIII inhibitors. The bispecific factor IX (FIX) and factor X (FX) monoclonal antibody emicizumab was approved in the US in November 2017, and in Europe in February 2018.
The overall objective of this study is to capture different approaches in the management of participants with HA and inhibitors, document current ITI approaches, and evaluate efficacy and safety of ITI, including the combination of FVIII and emicizumab. Patients will be assigned to 1 of 3 groups based on the treatments they receive:
844 studies on the registry are indexed under Hemophilia A; 138 are open to participants now.
This study's planned enrollment of 120 is above the median of 81 across 310 observational studies indexed under Hemophilia A.
Browse Hemophilia A studies →Emory University is the lead sponsor of 1,405 studies on the registry; 225 are open to participants now.
Of its 237 completed or terminated interventional studies of FDA-regulated products, 178 (75%) have results posted.
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The study population includes males with haemophilia A who have delveloped inhibitors to any FVIII product. Participants starting treatment after study inclusion will have all data recorded prospectively while those who have already started treatment can enter if detailed retrospective documentation is available. Participants will be observed for a maximum of 5 years.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants receiving immune tolerance induction with either Nuwiq, octanate, or wilate. As needed, aPCC/rFVIIa will be administered to treat bleeding episodes or during surgery and for prophylaxis.
Biological: Nuwiq · Biological: Octanate · Biological: Wilate · Biological: Recombinant factor VIIa (rFVIIa) · Biological: Activated prothrombin complex concentrate (aPCC)
Participants receiving immune tolerance induction with either Nuwiq, octanate, or wilate, in combination with emicizumab prophylaxis. As needed, aPCC/rFVIIa will be administered to treat bleeding episodes or during surgery.
Biological: Nuwiq · Biological: Octanate · Biological: Wilate · Biological: Emicizumab · Biological: Recombinant factor VIIa (rFVIIa) · Biological: Activated prothrombin complex concentrate (aPCC)
Participants receiving routine prophylaxis with emicizumab, aPCC, or rFVIIa without immune tolerance induction. On-demand aPCC/rFVIIa can be used as needed to treat bleeding episodes or during surgery.
Biological: Emicizumab · Biological: Recombinant factor VIIa (rFVIIa) · Biological: Activated prothrombin complex concentrate (aPCC)
Nuwiq is a recombinant FVIII concentrate from a human cell line. It is administered via intravenous injection at a dosage determined by the investigator's discretion, in consideration of the participants' clinical condition and prescribing information.
Octanate is a high-purity human Factor VIII / von Willebrand Factor (VWF) concentrate. It is administered via intravenous injection at a dosage determined by the investigator's discretion, in consideration of the participants' clinical condition and prescribing information.
Wilate is a high-purity human von Willebrand Factor (VWF)/Factor VIII concentrate. It is administered via intravenous injection at a dosage determined by the investigator's discretion, in consideration of the participants' clinical condition and prescribing information.
Emicizumab is a therapeutic antibody which brings activated factor IX and factor X together It is administered via subcutaneous injection at a dosage determined by the investigator's discretion, in consideration of the participants' clinical condition and prescribing information.
Also known as: Hemlibra
Recombinant factor VIIa (rFVIIa) is a blood factor VII manufactured using recombinant technology. It is administered via intravenous injection at a dosage determined by the investigator's discretion, in consideration of the participants' clinical condition and prescribing information.
Also known as: NovoSeven
Activated prothrombin complex concentrate (aPCC) is an anti-inhibitor coagulant complex acting on multiple pathways to facilitate coagulation. It is administered via intravenous injection at a dosage determined by the investigator's discretion, in consideration of the participants' clinical condition and prescribing information.
Also known as: FEIBA
Proportion of participants achieving inhibitor titer < 0.6 Bethesda units (BU)/mL L for at least 2 consecutive measurements
The proportion of participants in Groups 1 and 2 achieving inhibitor titer \< 0.6 Bethesda units (BU)/mL L for at least 2 consecutive measurements will be determined. FVIII inhibitor titer is measured at baseline and throughout the study, according to standard of care.
Time frame: Up to 5 years
Proportion of participants achieving FVIII recovery ≥ 66% of the predefined reference value of 1.5% IU/kg body weight (Groups 1 and 2)
The proportion of participants in Groups 1 and 2 achieving FVIII recovery ≥ 66% of the predefined reference value of 1.5% IU/kg body weight will be determined. Once inhibitor has become negative (\< 0.6 BU/mL), FVIII plasma levels are measured prior to and approximately 15 to 30 minutes after FVIII to evaluate FVIII recovery.
Time frame: Up to 5 years
Proportion of participants achieving FVIII half-life ≥ 6 h (Groups 1 and 2)
The proportion of participants in Groups 1 and 2 achieving FVIII half-life ≥ 6 h will be determined. Once inhibitor has become negative (\< 0.6 BU/mL), FVIII plasma levels are measured prior to and at 15-30 minutes and 2, 4, 8-12, and 24 hours after administration of the immune tolerance induction (or prophylactic FVIII) to evaluate half-life; when FVIII trough levels are \> 1% during regular prophylaxis, half-life can be evaluated from fewer samples or using a population pharmacokinetic model.
Time frame: Up to 5 years
Annualized bleeding rate
Annualized rate of all bleeding episodes will be reported and compared between all 3 study groups.
Time frame: Up to 5 years
Time to achieve immune tolerance induction outcome
The time it takes to achieve immune tolerance induction will be assessed in Groups 1 and 2. Immune tolerance induction success is defined as inhibitor titer \< 0.6 BU/mL for at least 2 consecutive measurements, FVIII recovery ≥ 66% of the predefined reference value of 1.5% IU/kg body weight, and half-life of FVIII ≥ 6 h.
Time frame: Up to 5 years
Frequency of emicizumab, aPCC, and rFVIIa use during immune tolerance induction
The number of times that participants in Groups 1 and 2 used emicizumab, aPCC, and rFVIIa during immune tolerance induction will be reported.
Time frame: Up to 5 years
Rate of FVIII inhibitor relapse
Rate of FVIII inhibitor relapses for participants in Groups 1 and 2 during an observational follow-up period in participants who have achieved complete immune tolerance induction success. Relapse is defined as inhibitor titer ≥ 0.6 BU/mL on ≥ 2 consecutive occurrences during the observational follow-up period after having achieved complete success and a prophylactic dose of ≤ 50 IU FVIII/kg every other day.
Time frame: Up to 5 years
Frequency of bleeding episodes
Frequency of all bleeding episodes (BEs), including all treated BEs, all spontaneous BEs, all joint BEs, and target joint BEs over time (≥ 3 bleeds in the same joint within 24 weeks) will be compared between study groups.
Time frame: Up to 5 years
Severity of bleeding episodes
Severity of all bleeding episodes (BEs), including all treated BEs, all spontaneous BEs, all joint BEs, and target joint BEs over time (≥ 3 bleeds in the same joint within 24 weeks) will be compared between study groups. Assessment of BE severity will be defined as: * Minor BEs are superficial muscle or soft tissue and oral bleeds * Moderate to major BEs are joint bleeds, bleeding into muscles, into oral cavity, known trauma * Major to life threatening BEs are bleedings in the cranium, abdomen, digestive system or chest, central nervous system bleeds, bleeding in the area of the pharynx or bleeds of the pelvic muscles, eyes/retina, fractures or head trauma
Time frame: Up to 5 years
Number of infusions required to control bleeding episodes
The number of infusions required to control bleeding episodes will be compared between study groups.
Time frame: Up to 5 years
Frequency of bleeding with surgical procedures
The frequency of bleeding during and after surgical procedures will be compared between study groups.
Time frame: Up to 5 years
Severity of bleeding with surgical procedures
The severity of bleeding during and after surgical procedures will be compared between study groups. The severity of bleeding during surgery will be defined as: * Excellent - Intraoperative blood loss was lower than or equal to the average expected blood loss for the type of procedure performed in a patient with normal haemostasis and of the same sex, age, and stature * Good - Intraoperative blood loss was higher than the average expected blood loss but lower or equal to the maximal expected blood loss for the type of procedure in a patient with normal haemostasis * Moderate - Intraoperative blood loss was higher than the maximum expected blood loss for the type of procedure performed in a patient with normal haemostasis, but haemostasis was controlled * None - Haemostasis was uncontrolled, necessitating a change in the treatment regimen
Time frame: Up to 5 years
Proportion of participants experiencing adverse drug reactions
The proportion of participants experiencing adverse drug reactions will be compared between study groups.
Time frame: Up to 5 years
Number of thrombotic events
The number of thrombotic events will be compared between study groups.
Time frame: Up to 5 years
Treatment costs
The cost (in dollars) of treatment will be compared between study groups.
Time frame: Up to 5 years
Plan to share: No
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