Phase 1 Haemophilia Trial, Recruiting
Who may be able to join
AI generated eligibility summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
Who might be able to join this trial:
- You are male and between 12 and 74 years old, and weigh at least 35 kg (about 77 lbs) at the time of signing the consent form
- You have been diagnosed with severe hemophilia A (with very low levels of clotting Factor VIII, below 1%) and do not have inhibitors (antibodies that block treatment)
- You have been taking emicizumab at a standard prescribed dose for at least 6 months
Who may not be able to join:
- You have a history of or are currently being treated for heart (coronary artery) disease, blood clots in veins or arteries, or conditions caused by reduced blood flow
- You have a medical or psychiatric condition — including thoughts of suicide or self-harm in the past year — or abnormal lab results that may make it unsafe for you to participate (confirm with trial site)
- You have a bleeding or clotting disorder other than hemophilia A
- You are currently taking certain medications that are not allowed in this study, or you are unwilling or unable to take medications that are required
- You have taken part in another clinical trial or received an experimental drug or vaccine within the past 30 days (or longer, depending on the drug), or plan to join another trial during this study
- Your platelet count is below 100,000/μl or your hemoglobin level is below 10 g/dL (a measure of red blood cells being too low)
- You have significantly abnormal kidney or liver function based on blood tests, or you have a known kidney or liver disease
- You are HIV positive and your CD4 cell count (an immune system measure) is 200/μl or below
- Your heart tracing test (ECG) shows significant abnormalities that the study doctor believes could affect your safety or the study results
- You have a surgery already planned during the study period
- You have had an allergic reaction to hamster protein or any ingredient in the study drug
- You are a staff member directly involved in running this trial, a family member of such staff, or an employee of the company sponsoring the trial
Important: Always verify eligibility with the trial site directly before applying.
Based on publicly available eligibility criteria from ClinicalTrials.gov. Verify directly with the trial site before acting. This is not medical advice.
Contact this trial
Principal Investigator: Pfizer CT.gov Call Center, Pfizer
Phone: 1-800-718-1021
Contact details sourced from ClinicalTrials.gov. Verify directly with the trial site before attending.
GP referral letter
Print a one-page summary to share with your doctor.
Trial details
Where this trial is recruiting
Primary endpoints
Incidence of marstacimab-related adverse events (AEs); Incidence of marstacimab-related serious AEs (SAEs)
Can't join this trial?
Data last synced from ClinicalTrials.gov: 27 July 2026. Trial status can change. Always verify current status directly with the trial site before making any decision.