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Coagulation Factor Replacement Therapy

Prophylactic Replacement Therapy for Hemophilia B

Phase 3
Waitlist Available
Research Sponsored by Pfizer
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Males ≥ 18 and <65 years of age with moderately severe to severe hemophilia B and documented FIX activity (≤2%) prior to baseline visit.
Previous experience with FIX therapy (≥50 documented exposure days to a FIX protein product such as recombinant, plasma-derived or extended half-life FIX product).
Must not have
Anti-AAV-Spark100 neutralizing antibody titer above the established threshold in hemophilia B subjects or Anti-AAV6 neutralizing antibody titer above the established threshold in hemophilia A subjects
Ineligibility due to hepatitis B or C status
Timeline
Screening 3 weeks
Treatment Varies
Follow Up 6 months
Awards & highlights
No Placebo-Only Group
Pivotal Trial

Summary

This trial is designed to see how well current prophylactic treatments work in hemophilia A and B patients before they receive gene therapy in a Phase 3 study. So far, only hemophilia B patients are being enrolled.

Who is the study for?
Adult males aged 18-65 with moderate to severe hemophilia B (FIX:C≤2%) who have used FIX therapy before, can follow the study plan, and don't have a history of FIX inhibitors or hypersensitivity. Hemophilia A enrollment is closed; only those with hemophilia B are being accepted now.
What is being tested?
The trial is assessing the effectiveness of standard FIX prophylaxis replacement therapy in men with hemophilia B as preparation for a Phase 3 gene therapy study. Participants must not have neutralizing antibodies against AAV-Spark100.
What are the potential side effects?
While specific side effects aren't listed for this observational study, common ones from FIX replacement may include allergic reactions, infusion site discomfort, headaches, and slight risk of blood clots.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below
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I am a man between 18 and 64 with severe hemophilia B and very low FIX activity.
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I have been treated with FIX therapy for at least 50 days.
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I plan to continue my FIX therapy throughout the study.
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I have never had a FIX inhibitor.
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My blood tests show no signs of resistance to FIX treatment.
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I am a man between 18 and 65 with severe hemophilia A and very low FVIII activity.
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I am a man between 18 and 65 with severe hemophilia B and very low FIX activity.
Select...
I have been treated with FIX therapy for at least 50 days.
Select...
I plan to continue my FIX replacement therapy throughout the study.
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I have never had a FIX inhibitor above normal levels.
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I am a man between 18 and 64 with severe hemophilia A and very low FVIII activity.
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I have been treated with FVIII therapy for at least 150 days.
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I plan to continue my FVIII therapy throughout the study.
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I have never had a Factor VIII inhibitor above normal levels.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:
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My body has high levels of specific antibodies against a gene therapy I received for hemophilia.
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I do not have hepatitis B or C.
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I am currently receiving treatment for hepatitis B or C.
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I have a serious liver condition.
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I have HIV with a CD4+ cell count of 200 or less.
Select...
I have previously received gene therapy for hemophilia.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~6 months
This trial's timeline: 3 weeks for screening, Varies for treatment, and 6 months for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.
Primary study objectives
Annualized bleeding rate (ABR)
Events of special interest (ESI):inhibitor against FIX or FVIII, thrombotic events, and FIX or FVIII hypersensitivity reactions
Incidence of serious adverse events
Secondary study objectives
Annualized infusion rate (AIR)
Dose and total factor consumption
Number of bleeding events (spontaneous and/or traumatic)

Awards & Highlights

No Placebo-Only Group
All patients enrolled in this study will receive some form of active treatment.
Pivotal Trial
The final step before approval, pivotal trials feature drugs that have already shown basic safety & efficacy.

Trial Design

2Treatment groups
Experimental Treatment
Group I: Standard of Care FVIII replacement therapyExperimental Treatment1 Intervention
Group II: Standard of Care FIX replacement therapyExperimental Treatment1 Intervention
Treatment
First Studied
Drug Approval Stage
How many patients have taken this drug
Standard of Care FVIII Replacement therapy
2019
N/A
~30

Find a Location

Who is running the clinical trial?

PfizerLead Sponsor
4,658 Previous Clinical Trials
17,877,074 Total Patients Enrolled
21 Trials studying Hemophilia B
4,875 Patients Enrolled for Hemophilia B
Pfizer CT.gov Call CenterStudy DirectorPfizer
3,544 Previous Clinical Trials
14,918,250 Total Patients Enrolled
22 Trials studying Hemophilia B
1,901 Patients Enrolled for Hemophilia B

Media Library

Standard of Care FIX Replacement therapy (Coagulation Factor Replacement Therapy) Clinical Trial Eligibility Overview. Trial Name: NCT03587116 — Phase 3
Hemophilia B Research Study Groups: Standard of Care FIX replacement therapy, Standard of Care FVIII replacement therapy
Hemophilia B Clinical Trial 2023: Standard of Care FIX Replacement therapy Highlights & Side Effects. Trial Name: NCT03587116 — Phase 3
Standard of Care FIX Replacement therapy (Coagulation Factor Replacement Therapy) 2023 Treatment Timeline for Medical Study. Trial Name: NCT03587116 — Phase 3
~29 spots leftby Nov 2025