ClinicalTrials.gov record
Recruiting Phase 3 Interventional

Open-Label Extension Study of Marstacimab in Hemophilia Participants With or Without Inhibitors

ClinicalTrials.gov ID: NCT05145127

Public ClinicalTrials.gov record NCT05145127. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced May 8, 2026, 12:27 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

AN OPEN-LABEL EXTENSION STUDY TO EVALUATE THE LONG-TERM SAFETY, TOLERABILITY, AND EFFICACY OF MARSTACIMAB PROPHYLAXIS IN SEVERE (COAGULATION FACTOR ACTIVITY <1%) HEMOPHILIA A PARTICIPANTS WITH OR WITHOUT INHIBITORS OR MODERATELY SEVERE TO SEVERE HEMOPHILIA B PARTICIPANTS (COAGULATION FACTOR ACTIVITY ≤2%) WITH OR WITHOUT INHIBITORS

Study identification

NCT ID
NCT05145127
Recruitment status
Recruiting
Study type
Interventional
Phase
Phase 3
Lead sponsor
Pfizer
Industry
Enrollment
245 participants

Conditions and interventions

Interventions

  • PF-06741086 Drug

Drug

Eligibility (public fields only)

Age range
1 Year to 74 Years
Sex
Male
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Nov 16, 2021
Primary completion
Jul 30, 2030
Completion
Jul 30, 2030
Last update posted
Apr 13, 2026

2021 – 2030

United States locations

U.S. sites
4
U.S. states
4
U.S. cities
4
Facility City State ZIP Site status
University of Iowa Iowa City Iowa 52242 Active, not recruiting
Northwell Health HTC New Hyde Park New York 11040 Recruiting
The Feinstein Institutes for Medical Research Philadelphia Pennsylvania 19195 Recruiting
Washington Institute for Coagulation d/b/a WACBD Seattle Washington 98101 Recruiting

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

Non-U.S. locations

This page focuses on the U.S. directory. The official record also lists 71 non-U.S. sites.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT05145127, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Apr 13, 2026 · Synced May 8, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT05145127 live on ClinicalTrials.gov.

View official ClinicalTrials.gov record →