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

JRCT ID: jRCT2041220046

Registered date:29/07/2022

Basic Information

• Recruitment status: Recruiting
• Health condition(s) or Problem(s) studied: Bleeding tendency in patients with hemophilia A and B with and without inhibitors
• Date of first enrollment: 09/09/2022
• Target sample size: 145
• Countries of recruitment: Canada,Japan,China,Japan,Croatia,Japan,France,Japan,Hong Kong,Japan,India,Japan,Italy,Japan,Korea, Republic of,Japan,Mexico,Japan,Oman,Japan,Serbia,Japan,South Africa,Japan,Spain,Japan,Taiwan,Japan,Turkey,Japan,United States,Japan
• Study type: Interventional

Intervention(s)

For participants aged >=12 years, marstacimab 300 mg SC for loading dose followed by 150 mg SC once weekly. 300 mg SC once weekly is prescribed for participants who meet dose escalation criteria.

For participants aged >=6 to <12 years, marstacimab 150 mg SC for loading dose followed by 75 mg SC once weekly. 150 mg SC once weekly is prescribed for participants who meet dose escalation criteria.

Outcome(s)

Primary Outcome

Primary Outcome Measures:
1.Number of subject reporting Adverse Events [ Time Frame: Baseline up to 7 years ]
2.Number of subjects reporting Serious Adverse Events [ Time Frame: Baseline up to 7 years ]
3.Incidence and severity of thrombotic events [ Time Frame: Baseline up to 7 years ]
4.Incidence and severity of thrombotic microangiopathy [ Time Frame: Baseline up to 7 years ]
5.Number of subjects reporting Disseminated intravascular coagulation/consumption coagulopathy [ Time Frame: Baseline up to 7 years ]
6.Incidence of clinically significant persistent NAb against marstacimab [ Time Frame: Baseline up to 7 years ]
7.Incidence and severity of injection site reaction [ Time Frame: Baseline up to 7 years ]
8.Clinically significant changes in vital signs from baseline [ Time Frame: Baseline up to 7 years ]
9.Incidence of clinically significant laboratory value abnormalities [ Time Frame: Baseline up to 7 years ]
10.Incidence of severe hypersensitivity and anaphylactic reactions [ Time Frame: Baseline up to 7 years ]

Secondary Outcome

1.Annualized rate of bleeding episodes [ Time Frame: Baseline up to 7 years ]
Derived for each subject for each treatment period by using the following formula: ABR = number of bleeds requiring treatments/ (days on treatment period / 365.25)
2.Total coagulation factor product consumption [ Time Frame: Baseline up to 7 years ]
3.Incidence of joint bleeds [ Time Frame: Baseline up to 7 years ]
4.Incidence of spontaneous bleeds [ Time Frame: Baseline up to 7 years ]
5.Incidence of target joint bleeds [ Time Frame: Baseline up to 7 years ]
6.Incidence of total bleeds (treated and untreated) [ Time Frame: Baseline up to 7 years ]
7.Change in joints measured by the HJHS [ Time Frame: Baseline up to 7 years ]
Change in joints as measured by the HJHS for participants >=4 years of age
8.Change in number of target joints per subject from baseline [ Time Frame: Baseline up to 7 years ]
9.Changes in Health Utilities Measure questionnaire data [ Time Frame: Baseline up to 7 years ]
10.Changes in Haem-A-QoL questionnaire data for participants >=17 years of age [ Time Frame: Baseline up to 7 years ]
11.Changes in Haemo-QoL questionnaire data [ Time Frame: Baseline up to 7 years ]
Haemo-QoL CII (Ages 8 to <12 years), Haemo-QoL (Ages 12 to <17)
12.Total bypass product consumption [ Time Frame: Baseline up to 7 years ]
13. Changes in EQ-5D questionnaire data [ Time Frame: Baseline up to 7 years ]
EQ-5D-Y Proxy (Ages >= 4 to <= 6 years), EQ-5D-Y Self (Ages >= 7 to <= 11 years), EQ-5D-5L (Ages >=12)

Key inclusion & exclusion criteria

• Age minimum: >= 1age old
• Age maximum: <= 74age old
• Gender: Male

Include criteria

All participants will have a minimum body weight as defined by parent studies
Participants who are willing and able to comply with all scheduled visits, treatment plan, laboratory tests, and other study procedures.
Participants have successfully completed participation in parent studies, defined as did not require "Early Termination"

Exclude criteria

Exclusion Criteria:
*Previous or current treatment for or history of coronary artery disease, venous or arterial thrombosis (CTCAE Grade >3), or ischemic disease (except catheter-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 parent study
*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

Related Information

• Primary Sponsor: Kawai Norisuke
• Secondary ID(s): NCT05145127