A Phase 2 interventional study of emicizumab in Acquired Hemophilia A, sponsored by University of Washington. Active, not recruiting at 16 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-11-05.
Sponsored by University of Washington · Phase 2, Interventional, and Treatment
This is a phase II multicenter open-label, single-arm prospective study to evaluate the efficacy of prophylactic emicizumab administered on a scheduled basis to prevent bleeds in patients with acquired hemophilia A (AHA).
Patients with AHA who are eligible will receive two loading doses of the study drug, emicizumab (6mg/kg on day 1 and 3 mg/kg on day 2) followed by once weekly subcutaneous emicizumab (1.5 mg/kg). Immunosuppression will be given concurrently as per investigator discretion. The primary endpoint (bleed rate) will be assessed after 12 weeks on study drug. If partial remission of the AHA has not been achieved, an additional 12 weeks of study drug may be given. A historical cohort and a study conducted in parallel in Germany (NCT04188639) will serve as control groups for evaluation of secondary endpoints provided the study cohort are comparable.
University of Washington is the lead sponsor of 1,433 studies on the registry; 225 are open to participants now.
Of its 158 completed or terminated interventional studies of FDA-regulated products, 136 (86%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
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.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
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.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Treatment with emicizumab
Drug: emicizumab
This study design uses emicizumab as a prophylaxis treatment to prevent bleeding for all participants, bypassing agents (with the exception of aPCC) and treatment of concomitant diseases will be given as clinically indicated. All eligible subjects with AHA will receive the same study medication consisting of: two loading doses of the emicizumab on day 1 and 2 followed by once weekly subcutaneous emicizumab injections. Immunosuppressive therapy (IST) will be given concurrently as per investigator discretion.
Also known as: Hemlibra (R)
Primary Outcome Meassure
Number of clinically significant bleeds after 12 weeks of study drug (emicizumab)
Time frame: 12 weeks
Incidence and severity of adverse events
Incidence and severity of adverse events, including thromboembolic events, thrombotic microangiopathy in the 12 weeks after starting emicizumab treatment; mortality and cause of death in the 24 weeks after starting emicizumab treatment.
Time frame: duration of entire study
Days of treatment with additional hemostatic agent
Days of treatment with and total dose of bypassing agents (recombinant factor VIIa, activated prothrombin complex concentrate) or recombinant porcine factor VIII (susoctocag alfa) or other factor VIII concentrates; specifics (drug, amount and timing) of IST started during the 12 weeks of emicizumab prophylaxis
Time frame: 12 weeks
Remission Rate
Number of patients achieving partial remission (PR) and complete remission (CR) over 12 and 24 weeks after starting emicizumab prophylaxis
Time frame: 1 to 24 weeks
Hospitalizations
Days in hospital during week 12 of emicizumab treatment
Time frame: 12 weeks
Total dose of additional hemostatic agent
Total dose of bypassing agents (recombinant factor VIIa, activated prothrombin complex concentrate) or recombinant porcine factor VIII (susoctocag alfa) or other factor VIII concentrates; specifics (drug, amount and timing) of IST started during the 12 weeks of emicizumab prophylaxis
Time frame: 12 weeks
Comparison of historic GTH-AH 01/2020 cohort/ Number of clinically significant bleeds
Number of clinically significant bleeds in the 12 weeks of emicizumab treatment or until achieving partial remission (PR) of AHA, whatever occurs first Incidence and severity of adverse events, thromboembolic events, thrombotic microangiopathy, in 12 weeks of treatment and mortality after 24 weeks Bleeding-free survival until week 12 after starting treatment
Time frame: 12 to 24 weeks
Comparison to a parallel German study cohort/ Number of clinically significant bleeds
Number of clinically significant bleeds per patient-week until death or week 12 after starting emicizumab treatment, whatever occurs first Incidence and severity of adverse events, thromboembolic events, in the 12 weeks of emicizumab treatment and mortality after 24 weeks Bleeding-free survival until week 12 of emicizumab treatment
Time frame: 12 to 24 weeks
Plan to share: Yes — All of the individual participant data collected during the trial will be shared with the research group of the parallel European study (NCT04188639). Data will be shared at the end of the study for analysis for a period of 2 years.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report
Time frame: Data will be shared with the research group of the parallel European study (NCT04188639) at the end of the study and will be available for 2 years.
Access criteria: Only researchers of this or the parallel trial (NCT04188639) will have access to this data.
Started Aug 2022 (actual). Primary completion is estimated for Jul 2026, 47 months after the start.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Jun 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Emicizumab
Factor 8 deficiency, acquired