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NCT03307980 · ClinicalTrials.gov registry record · Phase 2

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

A Phase 2 study of Hemophilia B, sponsored by Pfizer.

Active
Registry status
Phase 2
Development phase
21
Enrollment target
20
Study locations

NCT03307980: Active Phase 2 study of Hemophilia B, sponsored by Pfizer.

NCT03307980 is a Phase 2 study of Hemophilia B that is active but no longer recruiting, run by Pfizer. The registered enrollment target is 21 participants, below the 96-participant average among 20 other Hemophilia B trials with a reported enrollment target (78% lower). The trial reports 20 study locations across 7 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT03307980, a Phase 2 study of Hemophilia B, is active but no longer recruiting, sponsored by Pfizer.

ACTIVE NOT RECRUITING
Registry status
Phase 2
Development phase
21 participants
Enrollment target
20
Study locations

Study 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.

Conditions Studied

Interventions

  • BIOLOGICAL PF-06838435 (formerly SPK-9001)

Study Locations (20)

Louisiana

  • LA Center for Bleeding and Clotting Disorders - Metairie - Metairie
  • Tulane Lakeside Hospital - Metairie
  • LA Center for Bleeding and Clotting Disorders - New Orleans
  • Tulane University Clinical Translational Unit - New Orleans
  • Tulane University Hospitals and Clinic - New Orleans
  • Tulane University School of Medicine - New Orleans
  • University Medical Center New Orleans - New Orleans
  • Louisiana Center for Advanced Medicine - Slidell

California

  • UC Davis Comprehensive Cancer Center - Sacramento
  • UC Davis Ellison Ambulatory Care Clinic - Sacramento
  • UC Davis Medical Center department of Radiology - Sacramento
  • UC Davis Medical Center - Sacramento
  • UC Davis Midtown Cancer Center - Sacramento
  • UC DavisHealth Main Hospital - Sacramento

Ontario

  • McMaster University Medical Centre - Hamilton Health Sciences - Hamilton
  • McMaster University - Hamilton

Mississippi

  • Mississippi Center for Advanced Medicine - Madison

New York

  • Weill Cornell Medicine - New York Presbyterian Hospital - New York

Pennsylvania

  • The Children's Hospital of Philadelphia - Philadelphia

New South Wales

  • Royal Prince Alfred Hospital - Camperdown

Trial Details

FieldValue
Enrollment Target 21 participants
Start Date 2017-06-22
Est. Completion 2029-10-25
Phase Phase 2
Pfizer

1,845 total trials

What the registry record for NCT03307980 still lists

NCT03307980 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 21 participants, a relatively small participant target, below the 96-participant average among 20 other Hemophilia B trials with a reported enrollment target (78% lower).

The record links to 1 condition, with Hemophilia B appearing as the primary indexed condition, and to 1 intervention - of which PF-06838435 (formerly SPK-9001) is the first listed.

NCT03307980 names 20 study sites across 7 states, led by Louisiana, California, Ontario.

Frequently Asked Questions

What is clinical trial NCT03307980 about?

NCT03307980 is a clinical study titled "Long-term Safety and Efficacy Study and Dose-Escalation Substudy of PF 06838435 in Individuals With Hemophilia B". 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. Participa...

What is the current status of trial NCT03307980?

This trial is currently active not recruiting. It is a Phase 2 study. The enrollment target is 21 participants. The study started on 2017-06-22. Estimated completion is 2029-10-25.

What conditions does trial NCT03307980 study?

This clinical trial studies the following conditions: Hemophilia B.

What interventions are being tested in trial NCT03307980?

The interventions under investigation include: PF-06838435 (formerly SPK-9001) (BIOLOGICAL).

Who is sponsoring clinical trial NCT03307980?

This trial is sponsored by Pfizer, which has 1,845 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT03307980 being conducted?

This trial has 20 study locations across California, Louisiana, Mississippi, New York, Pennsylvania. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for Hemophilia B

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT03307980's enrollment target sits among peer trials

21 15th of 20 higher than 6 of 20 other Hemophilia B trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Hemophilia B trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT03307980, the US trial registry maintained by the National Library of Medicine. NCT03307980 (small enrollment · wide site footprint · active not recruiting) retrieved and formatted by PlainTrial, see methodology.