Clinical Trial

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

Completed Phase 2
View on ClinicalTrials.gov →
Summary
Long-term safety and efficacy follow-up for participants with Hemophilia B who were previously treated in the C0371005 (formerly SPK-9001-101) study, and a dose-escalation sub-study evaluating safety, tolerability, and kinetics of a higher dose with long-term safety and efficacy follow-up. Participants in the substudy do not need to have participated in C0371005.
Protocol Amendment History 5 changes
critical Trial completed 2026-08-12
notable Primary completion moved earlier: 2029-05-29 -> 2026-07-23 2026-08-12
minor Completion moved earlier: 2029-10-25 -> 2026-07-23 2026-08-12
notable Trial sites expanded: 12 -> 25 locations 2026-05-13
notable Trial sites reduced: 25 -> 12 locations 2026-05-06
Trial Details
NCT Number NCT03307980
Lead Sponsor Pfizer
Conditions Hemophilia B
Enrollment 21 participants
Start Date 2017-06-22
Primary Completion 2026-07-23 (estimated)
Study Completion 2026-07-23 (estimated)
Updated on ClinicalTrials.gov 2026-08-11