A Study to Evaluate the Efficacy and Safety of Factor IX Gene Therapy With PF-06838435 in Adult M… (NCT03861273) | Clinical Trial Compass
Active — Not RecruitingPhase 3
A Study to Evaluate the Efficacy and Safety of Factor IX Gene Therapy With PF-06838435 in Adult Males With Moderately Severe to Severe Hemophilia B
United States, Australia, Brazil51 participantsStarted 2019-07-29
Plain-language summary
This study will evaluate the efficacy and safety of PF-06838435 (a gene therapy drug) in adult male participants with moderately severe to severe hemophilia B (participants that have a Factor IX circulating activity of 2% or less). The gene therapy is designed to introduce genetic material into cells to compensate for missing or non-functioning Factor IX. Eligible study participants will have completed a minimum 6 months of routine Factor IX prophylaxis therapy during the lead in study (C0371004). Participants will be dosed once (intravenously) and will be evaluated over the course of 6 years. The main objective of the study will evaluate the annualized bleeding rate \[ABR\] for participants treated with gene therapy versus standard of care (SOC) therapy (FIX prophylaxis replacement regimen).
Who can participate
Age range
18 Years – 65 Years
Sex
MALE
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
* Males who completed 6 months of Factor IX prophylaxis therapy during the lead-in study (C0371004) prior to providing consent at the screening visit for this study.
* Documented moderately severe to severe hemophilia B (Factor IX activity \< =2%)
* Previous experience with FIX therapy (=\>50 documented exposure days to a FIX protein product)
* Suspension of prophylaxis therapy for hemophilia B after administration of the study drug
* Laboratory values (hemoglobin, platelets and creatinine) within study specified limits
* Agree to contraception until components of the drug are eliminated from their body
* Capable of giving signed informed consent
Exclusion Criteria
* Anti-AAVRh74var neutralizing antibodies (nAb) titer above the established threshold (ie, positive for nAb).
* History of inhibitor to Factor IX or inhibitor detected during screening. Clinical signs or symptoms of decreased response to Factor IX
* Hypersensitivity to Factor IX replacement product or IV immunoglobulin administration
* History of chronic infection or other chronic disease
* Any conditions associated with increased thromboembolic risk
* Concurrent clinically significant major disease or condition unsuitable for participation and/or may interfere with the interpretation of study results
* Laboratory values at screening visit that are abnormal or outside acceptable study limits
* Current unstable liver or biliary disease
* Currently on antiviral therapy for hepatitis B or C
* Pla…
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Annualized Bleeding Rate (ABR) for Total Bleeds (Treated and Untreated) From Week 12 to Month 15
Timeframe: Pre-infusion period: minimum of 6 months through first dose of current study, an average of 1.31 years (FIX Prophylaxis arm); Week 12 to Month 15 post infusion in current study (PF-06838435 arm)