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NCT05145127 · ClinicalTrials.gov registry record · Phase 3

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

A Phase 3 study of Hemophilia A and Hemophilia B, sponsored by Pfizer.

Recruiting
Registry status
Phase 3
Development phase
245
Enrollment target
20
Study locations

NCT05145127: Recruiting Phase 3 study of Hemophilia A and Hemophilia B, sponsored by Pfizer.

NCT05145127 is a Phase 3 study of Hemophilia A and Hemophilia B that is actively recruiting participants, run by Pfizer. The registered enrollment target is 245 participants, above the 86-participant average among 42 other Hemophilia A trials with a reported enrollment target (185% higher). The trial reports 20 study locations across 13 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT05145127, a Phase 3 study of Hemophilia A and Hemophilia B, is actively recruiting participants, sponsored by Pfizer.

RECRUITING
Registry status
Phase 3
Development phase
245 participants
Enrollment target
20
Study locations

Study Summary

Study B7841007 is an open-label extension study to assess the long-term safety, tolerability, and efficacy of prophylaxis treatment with marstacimab in participants who did not require "Early Termination" from the Phase 3 Study B7841005 and from the Phase 3 Study B7841008. Study B7841005: approximately 145 adolescent and adult participants 12 to \<75 years of age with severe hemophilia A or moderately severe to severe hemophilia B (defined as FVIII activity \<1% or FIX activity ≤2%, respectively) with or without inhibitors are expected to be enrolled in Study B7841005 during which they will receive prophylaxis (defined as treatment by SC injection of marstacimab). Study B7841008: this is an ongoing Phase 3, open-label study in pediatric participants \<18 years of age with severe hemophilia A (FVIII Coagulation Factor Activity \<1%) or moderately severe to severe hemophilia B (FIX Coagulation Factor Activity ≤2%). A sequential approach will be used in enrolling at least 100 pediatric participants, at least 20 of which will be aged ≥12 to \<18 years and at least 80 participants will be aged ≥1 to \<12 years. At the start of study B7841008, the dosing and data available in adolescent and adult participants in Study B7841005 supported the initiation of B7841008 study in participants aged ≥12 to \<18 years. Subsequently, additional safety and efficacy data from adolescent participants in Study B7841005 became available for benefit/risk assessment in support of dosing participants aged ≥6 to \<12 years. Based on the positive benefit/risk assessment conducted by both internal Pfizer review and eDMC review, dosing of the ≥6 to \<12 years age group was initiated in June 2023 in B7841008 Study. Data from participants ≥6 years from B7841008 Study and Study B7841005 will support the dosing of participants aged ≥1 to \<6 years. All participants will be provided the prefilled pen (PFP) for administration of marstacimab in the study. Use of the prefilled syringe (PFS) will be p

Conditions Studied

Hemophilia A Hemophilia B

Interventions

  • DRUG PF-06741086

Study Locations (20)

Other

  • Beijing Children's Hospital, Capital Medical University - Beijing
  • Klinicki bolnicki centar Zagreb - Zagreb
  • Hôpital Universitaire Necker Enfants Malades - Paris
  • Prince of Wales Hospital - Hong Kong
  • Queen Mary Hospital - Hong Kong

Ontario

  • Hamilton Health Sciences - McMaster University Medical Centre - Hamilton
  • Hamilton Health Sciences - McMaster University Medical Centre - Hamilton

Guizhou

  • The Affiliated Hospital of Guizhou Medical University - Guiyang
  • The Affiliated Hospital of Guizhou Medical University - Guiyang

Tianjin Municipality

  • Institute of hematology&blood disease hospital - Tianjin
  • Institute of hematology&blood disease hospital - Tianjin

Iowa

  • University of Iowa - Iowa City

New York

  • Northwell Health HTC - New Hyde Park

Washington

  • Washington Institute for Coagulation d/b/a WACBD - Seattle

Victoria

  • Royal Children's Hospital - Melbourne

Trial Details

FieldValue
Enrollment Target 245 participants
Start Date 2021-11-17
Est. Completion 2030-07-31
Phase Phase 3
Pfizer

1,845 total trials

What NCT05145127 shows while recruiting

NCT05145127 is an interventional study that assigns participants to a tested intervention. The registered 245 participants enrollment target is mid-sized for trials with a published cap, above the 86-participant average among 42 other Hemophilia A trials with a reported enrollment target (185% higher).

The record links to 2 conditions, with Hemophilia A appearing as the primary indexed condition, and to 1 intervention - of which PF-06741086 is the first listed.

NCT05145127 names 20 study sites across 13 states, led by Other, Ontario, Guizhou.

Frequently Asked Questions

What is clinical trial NCT05145127 about?

NCT05145127 is a clinical study titled "Open-Label Extension Study of Marstacimab in Hemophilia Participants With or Without Inhibitors". Study B7841007 is an open-label extension study to assess the long-term safety, tolerability, and efficacy of prophylaxis treatment with marstacimab in participants who did not require "Early Termination" from the Phase 3 Study B7841005 and from the Phase 3 Study B7841008. Study B7841005: approxima...

What is the current status of trial NCT05145127?

This trial is currently recruiting. It is a Phase 3 study. The enrollment target is 245 participants. The study started on 2021-11-17. Estimated completion is 2030-07-31.

What conditions does trial NCT05145127 study?

This clinical trial studies the following conditions: Hemophilia A, Hemophilia B.

What interventions are being tested in trial NCT05145127?

The interventions under investigation include: PF-06741086 (DRUG).

Who is sponsoring clinical trial NCT05145127?

This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT05145127 being conducted?

This trial has 20 study locations across Iowa, New York, Washington, Victoria, Alberta. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Learn More About Clinical Trials

Similar trials for Hemophilia A

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT05145127's enrollment target sits among peer trials

245 4th of 42 higher than 39 of 42 other Hemophilia A trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Hemophilia A trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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More recruiting context for NCT05145127

Source: ClinicalTrials.gov NCT05145127, the US trial registry maintained by the National Library of Medicine. NCT05145127 (mid enrollment · wide site footprint · recruiting) retrieved and formatted by PlainTrial, see methodology.