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A Clinical Trial of Study Medicine (Marstacimab) in Pediatric Patients With Hemophilia A or Hemophilia B
NCT05611801 · View on ClinicalTrials.gov ↗
Study Summary
The purpose of this clinical trial is to learn about the safety and effects of the study medicine (called marstacimab) for the potential treatment of hemophilia in pediatric patients. This study will enroll pediatric participants from ages 1 to 17 years in a sequential manner. The study will open enrollment to adolescent participants aged 12 to 17 years first. Then children aged 6 to 11 years will be permitted to enroll. Lastly, children aged 1 to 5 years will be permitted to enroll. This study will enroll participants who: * have severe Hemophilia A or moderately severe to severe Hemophilia B (with or without inhibitors) * have accurate historical records documenting all factor VIII, factor IX, or bypass agent infusions and hemophilia bleed events for at least 1 year prior to entering the study * if a non-inhibitor patient, must be on a stable routine prophylaxis regimen with factor VIII or factor IX replacement products for at least 12 months prior to study entry * if an inhibitor patient, must be on an on-demand bypass treatment regimen during the 12 months prior to study entry All participants in this study will receive marstacimab to use prophylactically. Marstacimab will be given once a week as a subcutaneous (under the skin) shot. The first dose of marstacimab will be given at the study site by the study site staff. During the 12-month treatment period, weekly doses of marstacimab can be given at home, or if preferred, the doses may be given by the study site staff. To help us determine if the study medicine is safe and effective, we will compare participant experiences when they are taking the study medicine to a historical period when they were not. Researchers want to see if the study medicine works to prevent the bleeding episodes commonly experienced by patients with Hemophilia. Participants will be in this study for about 14 months (approximately 1 month in a Screening period, 12 months receiving treatment, and 1 month in a follow-up period) durin
Conditions Studied
Interventions
- DRUG marstacimab
Study Locations (20)
Other
- Arbesu Hematología — Mendoza
- Hôpital Universitaire Necker Enfants Malades — Paris
- Charité Campus Virchow-Klinikum — Berlin
Hubei
- Tongji Hospital of Tongji Medical College of Huazhong University of Science and Technology — Wuhan
- Tongji Hospital of Tongji Medical College of HUST/Pediatric Hematology Department Pharmacy — Wuhan
Utah
- Intermountain - Primary Children's Hospital — Salt Lake City
New South Wales
- Sydney Children's Hospital — Randwick
Victoria
- Royal Children's Hospital — Melbourne
Vienna
- Medizinische Universität Wien — Vienna
Espírito Santo
- HEMOES — Vitória
Alberta
- Stollery Children's Hospital — Edmonton
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 100 participants |
| Start Date | 2022-12-09 |
| Est. Completion | 2028-09-10 |
| Phase | Phase 3 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT05611801
The ClinicalTrials.gov registry entry for NCT05611801 describes a study currently listed as recruiting. It is categorized as Phase 3, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 100 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Pfizer, which has 769 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 2 conditions, with Hemophilia A appearing as the primary indexed condition, and to 1 intervention — of which marstacimab is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT05611801 reports 20 study locations spanning 17 distinct geographic areas — top geographies include Other, Hubei, Utah. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT05611801 about?
NCT05611801 is a clinical study titled "A Clinical Trial of Study Medicine (Marstacimab) in Pediatric Patients With Hemophilia A or Hemophilia B". The purpose of this clinical trial is to learn about the safety and effects of the study medicine (called marstacimab) for the potential treatment of hemophilia in pediatric patients. This study will enroll pediatric participants from ages 1 to 17 years in a sequential manner. The study will open e...
What is the current status of trial NCT05611801?
This trial is currently recruiting. It is a Phase 3 study. The enrollment target is 100 participants. The study started on 2022-12-09. Estimated completion is 2028-09-10.
What conditions does trial NCT05611801 study?
This clinical trial studies the following conditions: Hemophilia A, Hemophilia B. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT05611801?
The interventions under investigation include: marstacimab (DRUG). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT05611801?
This trial is sponsored by Pfizer, which has 769 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT05611801 being conducted?
This trial has 20 study locations across Utah, New South Wales, Victoria, Vienna, Espírito Santo. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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