Long-term Safety and Efficacy Study and Dose-Escalation Substudy of PF 06838435 in Individuals With Hemophilia B

Launched by PFIZER · Oct 6, 2017

Keywords

ClinConnect Summary

This clinical trial is focused on studying a treatment called PF 06838435 for men with Hemophilia B, a condition where the blood doesn't clot properly due to low levels of a protein called factor IX. The trial is looking at both the long-term safety and effectiveness of this treatment for individuals who have participated in a previous study, as well as evaluating whether a higher dose of the treatment is safe and effective for new participants.

To be eligible for the trial, participants must be men aged 18 to 65 who have a confirmed diagnosis of Hemophilia B and have received enough previous treatment (at least 50 days) with factor IX products. Participants also need to be in good health overall and agree to certain precautions, like not donating sperm during the study. Those who join can expect regular monitoring to ensure their safety and to see how well the treatment is working over time. It’s important to remember that this trial is currently not recruiting new participants, but it is still active for those who qualify.

Gender

MALE

Eligibility criteria

• This study is currently only enrolling into the dose-escalation substudy with subsequent long-term follow-up. The Eligibility Criteria for entry into the dose-escalation substudy is presented below:
• Inclusion Criteria:
• • 1. Able to provide informed consent and comply with requirements of the study
• • 2. Males age 18 to 65 years with confirmed diagnosis of hemophilia B (≤2 IU/dL or ≤2% endogenous factor IX)
• • 3. Received ≥50 exposure days to factor IX products
• • 4. No measurable factor IX inhibitor as assessed by the central laboratory and have no prior history of inhibitors to factor IX protein
• • 5. Agree to refrain from donating sperm and either abstain from intercourse or use reliable barrier contraception until 3 consecutive semen samples are negative for vector sequences
• Exclusion Criteria:
• • 1. Evidence of active hepatitis B or C
• • 2. Currently on antiviral therapy for hepatitis B or C
• • 3. Have significant underlying liver disease
• • 4. Serological evidence\* of HIV-1 or HIV-2 with CD4 counts ≤200/mm3 (\* participants who are HIV+ and stable with CD4 count \>200/mm3 and undetectable viral load are eligible to enroll)
• • 5. Neutralizing antibody titers to the capsid portion of PF-06838435 above the established threshold
• • 6. Sensitivity to heparin or heparin induced thrombocytopenia; sensitivity to any of the study interventions, or components thereof, or drug or other allergy
• • 7. Previously dosed in a gene therapy research trial at any time or in an interventional clinical study within 3 months of screening visit
• • 8. Any concurrent clinically significant major disease or condition
• • 9. Unable or unwilling to comply with the study procedures