NCT06998524 · Hoffmann-La Roche
A Study to Assess the Efficacy and Safety of Emicizumab in Participants With Type 3 Von Willebrand Disease
(WILL-EMI)
What this study is about
This is a Phase III, conducted at multiple hospitals, where both patients and doctors know the treatment given clinical study designed to evaluate the effectiveness, safety, how the drug moves through the body, and how the drug affects the body of emicizumab prophylaxis in participants aged 1 month and above, who have been diagnosed with Type 3 von Willebrand disease (VWD).
View original scientific description
This is a Phase III, multicenter, open-label clinical study designed to evaluate the efficacy, safety, pharmacokinetics, and pharmacodynamics of emicizumab prophylaxis in participants aged 1 month and above, who have been diagnosed with Type 3 von Willebrand disease (VWD). Participants on prior standard of care (SOC) on-demand therapy will be assessed via a randomized comparison (Arm A - emicizumab prophylaxis and Arm B - continuation of SOC on-demand therapy), while participants on prior SOC prophylactic therapy (Arm C - emicizumab prophylaxis) will be assessed via intra-participant analysis with data obtained from the preceding non-interventional study (NIS), WP45335 (NCT06883240).
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Confirmed diagnosis of Type 3 von Willebrand disease (VWD), based on medical records
- Preexisting medical record verifying the status of von Willebrand factor (VWF) inhibitor (positive or negative, including titer if available)
- Adequate hematologic, hepatic, and renal function
- For participants of childbearing potential: agreement to remain abstinent or adhere to the contraception requirements Additional Inclusion Criteria for Arms A and B:
- Age ≥1 month at the time of signing Informed Consent/Assent Form
- Documented previous use of on-demand therapy with intermittent (less than once a week) on-demand SOC therapy for VWD
- Having ≥2 treated bleeds (except menstrual bleeds) with factor concentrate within 24 weeks prior to enrollment Additional Inclusion Criteria for Arm C:
- Age ≥2 years at the time of signing Informed Consent/Assent Form
- Documented and confirmed previous use of SOC prophylactic therapy for VWD (1-3 times weekly, as per prescribed dose) as described in the eligibility of Study WP45335
- Have completed all study requirements as defined in the WP45335 protocol for at least 24 weeks
Exclusion criteria
- Inherited or acquired bleeding disorder other than Congenital Type 3 VWD
- History of gastrointestinal bleeding within 18 months prior to enrollment, or any previous diagnosis of angiodysplasia
- History of intracranial hemorrhage
- Previous or current treatment for thromboembolic disease or signs of thromboembolic disease
- Other conditions (e.g., certain autoimmune diseases) that may increase risk of bleeding or thrombosis
- History of clinically significant hypersensitivity associated with monoclonal antibody therapies or components of the emicizumab injection
- Use of systemic immunomodulators (e.g., interferon) at enrollment or planned use during the study, with the exception of anti-retroviral therapy
Where
- Sacramento, California
- Gainesville, Florida
- Minneapolis, Minnesota
- St Louis, Missouri
- Richmond, Virginia
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 10, 2026 · Source of record for eligibility and locations