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

Brief Title

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

Official Title

AN OPEN-LABEL EXTENSION STUDY TO EVALUATE THE LONG-TERM SAFETY, TOLERABILITY, AND EFFICACY OF MARSTACIMAB PROPHYLAXIS IN PARTICIPANTS WITH SEVERE HEMOPHILIA A AND B WITH OR WITHOUT INHIBITORS

Brief 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. 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 this study during which they will receive
      prophylaxis (defined as treatment by SC injection of marstacimab). The dosing regimen of
      marstacimab is 150 mg SC once weekly.

      All participants will be provided the PFP for administration of marstacimab in the study. Use
      of the PFS will be permitted at the investigator's discretion for those participants who have
      difficulty with administration of the PFP. Additionally, participants will be provided the
      PFS for use in this study in countries where the PFS is anticipated to be the only
      presentation available commercially. In addition, an optional, open-label, single arm,
      substudy using the PFP will be administered to the first approximately 20 participants
      rolling over from Study B7841005 who agree to participate in the substudy.

Study Phase

Phase 3

Study Type

Interventional

Primary Outcome

Number of subject reporting Adverse Events

Secondary Outcome

 Annualized rate of bleeding episodes

Condition

Hemophilia A

Intervention

PF-06741086

Study Arms / Comparison Groups

 PF-06741086

Description:  300 milligrams(mg) subcutaneous (sc) loading dose followed by 150 mg sq once weekly (qw). 300 mg sc qw is prescribed for participants who meet dose escalation criteria.

Publications

* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.

Recruitment Information

Recruitment Status

Drug

Estimated Enrollment

Start Date

November 17, 2021

Completion Date

July 31, 2030

Primary Completion Date

July 31, 2030

Eligibility Criteria

        Inclusion Criteria:

          -  All participants will have a minimum body weight of 35 kg

          -  Participants have successfully completed participation in study B7841005, defined as
             did not require "Early Termination" from study B7841005

        Exclusion Criteria:

          -  Previous or current treatment for or history of coronary artery disease, venous or
             arterial thrombosis (CTCAE Grade >3), or ischemic disease (except catherter-associated
             thrombosis)

          -  Abnormal renal function as defined by eGFR <30 mL.min/1.73 m(2)

          -  Known planned surgical procedure during the planned study period

          -  Unstable hepatic function as determined by the Investigator clinical assessment and
             review of the participant's most recent laboratory results, which would make the
             participant inappropriate for the study

          -  For participants known to be HIV+, worsening disease status as determined by the
             Investigator clinical assessment and review of participant's most recent laboratory
             results, to include recent locally available CD4 count (if available), which would
             make the participant inappropriate for the study

          -  Regular, concomitant therapy with immunomodulatory drugs (eg, IVIG, and routine
             systemic corticosteroids, rituximab)

          -  Ongoing or planned use of immune tolerance induction or prophylaxis with FVIII or FIX
             replacement during the study

          -  Participation in other study involving investigational drug(s) or investigational
             vaccine(s) within 30 days or 5 half-lives prior to or during study participation, with
             the exception of participation in study B7841005

          -  Investigator site staff or Pfizer employees directly involved in the conduct of the
             study, site staff otherwise supervised by the Investigator, and their respective
             family members

Gender

Male

Ages

12 Years - 74 Years

Accepts Healthy Volunteers

No

Contacts

Pfizer CT.gov Call Center, 1-800-718-1021, [email protected]

Location Countries

Hong Kong

Location Countries

Hong Kong

Administrative Informations

NCT ID

NCT05145127

Organization ID

B7841007

Secondary IDs

PHASE 3 ANTI-TFPI OLE

Responsible Party

Sponsor

Study Sponsor

Pfizer

Study Sponsor

Pfizer CT.gov Call Center, Study Director, Pfizer

Verification Date

May 2022