Medical Information Only. Always consult your healthcare provider before enrolling in any clinical trial.
A Study to Learn About How Changing Therapy From Emicizumab to Marstacimab Affects People With the Severe Hemophilia A.
NCT06703606 · View on ClinicalTrials.gov ↗
Study Summary
The purpose of the study is to learn about safety, how the body processes marstacimab and how it works in patients with severe hemophilia A without inhibitors. Hemophilia A is rare bleeding disorder where the blood doesn't clot normally. This causes a person to bleed a lot, even from a small cut. These patients who are on emicizumab medicine for routine prophylaxis for at least 6 months, and desire to switch to marstacimab medicine. Inhibitors are antibodies that the immune system develops because it sees the infused clotting factor as a foreign substance that needs to be destroyed. Antibodies are proteins that eat up the activated factor before it has time to stop the bleeding. Prophylaxis are preventive medicines. This study is seeking for participants: * with severe Hemophilia A withouth inhibitors who are on emicizumab treatment for at least 6 months. * must be 12 to less than 75 years old * must have a body weight of at least 35 kilograms. The results from this study will serve as a guide to doctors and their hemophilia A patients who will change their medicines in the real-world clinical setting. Patients who can take part in the study will receive marstacimab medicine as weekly injections under the skin of 150 milligrams for 4 months. Study treatment with marstacimab will be initiated no earlier than 14 days after last dose of emicizumab. The study can last up to 6 months. The sponsor will provide marstacimab. Patients will continue their usual treatment with the infused clotting factor for their bleeds when taking part in the study. Roll-over into an optional study treatment extension period will be available to participants who wish to continue prophylaxis with marstacimab in countries where it is not commercially available.
Conditions Studied
Interventions
- DRUG MARSTACIMAB
Study Locations (1)
California
- Orthopaedic Institute for Children — Los Angeles
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 15 participants |
| Start Date | 2025-05-13 |
| Est. Completion | 2027-05-05 |
| Phase | Phase 1 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT06703606
The ClinicalTrials.gov registry entry for NCT06703606 describes a study currently listed as recruiting. It is categorized as Phase 1, 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 15 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 1 condition, with Severe 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: NCT06703606 reports 1 study location spanning 1 distinct geographic area — top geographies include California. 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 NCT06703606 about?
NCT06703606 is a clinical study titled "A Study to Learn About How Changing Therapy From Emicizumab to Marstacimab Affects People With the Severe Hemophilia A.". The purpose of the study is to learn about safety, how the body processes marstacimab and how it works in patients with severe hemophilia A without inhibitors. Hemophilia A is rare bleeding disorder where the blood doesn't clot normally. This causes a person to bleed a lot, even from a small cut. T...
What is the current status of trial NCT06703606?
This trial is currently recruiting. It is a Phase 1 study. The enrollment target is 15 participants. The study started on 2025-05-13. Estimated completion is 2027-05-05.
What conditions does trial NCT06703606 study?
This clinical trial studies the following conditions: Severe Hemophilia A. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT06703606?
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 NCT06703606?
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 NCT06703606 being conducted?
This trial has 1 study location across California. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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