CompletedPhase 3

A Study to Evaluate Prospective Efficacy and Safety Data of Current FIX Prophylaxis Replacement Therapy in Adult Hemophilia B Subjects (FIX:C≤2%) or Current FVIII Prophylaxis Replacement Therapy in Adult Hemophilia A Subjects (FVIII:C≤1%)

United States212 participantsStarted 2018-07-26

Plain-language summary

To establish baseline prospective efficacy data of current FIX prophylaxis replacement therapy in the usual care setting of hemophilia B subjects, who are negative for nAb to AAV-Spark100, prior to the Phase 3 gene therapy study. To establish baseline prospective efficacy data of current FVIII prophylaxis replacement therapy in the usual care setting of hemophilia A subjects, who are negative for nAb to AAV6, prior to the Phase 3 gene therapy study. The enrollment for hemophilia A participants is completed. At this time participants are only being enrolled for hemophilia B cohort.

Who can participate

Age range18 Years – 64 Years

SexMALE

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion criteria

✓. Evidence of a signed and dated informed consent document indicating that the participant has been informed of all pertinent aspects of the study.
✓. Willing and able to comply with scheduled visits, FIX prophylaxis treatment plan, laboratory tests and other study procedures.
✓. 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).
✓. Participants on FIX prophylaxis replacement therapy (recombinant, plasma-derived or extended half-life FIX product) must have the intention to remain on FIX prophylaxis replacement therapy for the duration of the study.
✓. No known hypersensitivity to FIX replacement product.
✓. No history of FIX inhibitor (clinical or laboratory-based assessment) defined as a titer
✓. Evidence of a signed and dated informed consent document indicating that the participant has been informed of all pertinent aspects of the study.

Exclusion criteria

What they're measuring

Annualized Bleeding Rate (ABR) for Treated Bleeds and All Bleeds During Prospective Data Collection Period in Hemophilia B Participants: Efficacy Analysis Set

Timeframe: During prospective data collection period (from baseline visit of the study [Day 1] up to end of study follow-up [maximum follow-up: 1269 days])

ABR for Treated Bleeds and All Bleeds During Prospective Data Collection Period in Hemophilia B Participants: Per-protocol Analysis Set

Timeframe: During prospective data collection period (from baseline visit of the study [Day 1] up to end of study follow-up [maximum follow-up: 1269 days])

ABR for Treated Bleeds and All Bleeds During Prospective Data Collection Period in Hemophilia B Participants: Protocol Amendment 5 Analysis Set

Timeframe: During prospective data collection period (from baseline visit of the study [Day 1] up to end of study follow-up [maximum follow-up: 1269 days])

ABR for Treated Bleeds and All Bleeds During Retrospective Data Collection Period in Hemophilia B Participants: Protocol Amendment 5 Analysis Set

Timeframe: During retrospective data collection period (12 months before screening collected in the hemophilia history case report form [CRF])

ABR for Treated Bleeds and All Bleeds From the Combined Retrospective and Prospective Data Collection Period in Hemophilia B Participants: Protocol Amendment 5 Analysis Set

Timeframe: From start of retrospective data collection period (12 months before screening collected in hemophilia history CRF) up to end of prospective data collection follow-up of period (maximum follow-up:1269 days), for a total of approximately 4.5 years

Trial details

NCT IDNCT03587116

SponsorPfizer

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2024-12-13

Results submitted2025-10-23

View on ClinicalTrials.gov More Hemophilia B trials

Plain-language summary

Who can participate

Age range18 Years – 64 Years

SexMALE

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion criteria

✓. Evidence of a signed and dated informed consent document indicating that the participant has been informed of all pertinent aspects of the study.
✓. Willing and able to comply with scheduled visits, FIX prophylaxis treatment plan, laboratory tests and other study procedures.
✓. 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).
✓. Participants on FIX prophylaxis replacement therapy (recombinant, plasma-derived or extended half-life FIX product) must have the intention to remain on FIX prophylaxis replacement therapy for the duration of the study.
✓. No known hypersensitivity to FIX replacement product.
✓. No history of FIX inhibitor (clinical or laboratory-based assessment) defined as a titer
✓. Evidence of a signed and dated informed consent document indicating that the participant has been informed of all pertinent aspects of the study.