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NCT04188509 · ClinicalTrials.gov registry record · Phase 3

Open-Label Extension of Voxelotor

A Phase 3 study, sponsored by Pfizer.

Terminated
Registry status
Phase 3
Development phase
162
Enrollment target

NCT04188509: Clinical Trial Phase 3 study, sponsored by Pfizer.

NCT04188509 is a Phase 3 study that was terminated before completion, run by Pfizer. The registered enrollment target is 162 participants, below the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (79% lower). According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT04188509, a Phase 3 study, was terminated before completion, sponsored by Pfizer.

TERMINATED
Registry status
Phase 3
Development phase
162 participants
Enrollment target

Study Summary

Open-label extension study of voxelotor for participants with Sickle Cell Disease who have participated in voxelotor clinical trials.

Primary Outcome

An AE was defined as any untoward medical occurrence associated with the use of a drug in humans, whether or not considered to be drug related. A treatment emergent AE was defined as an AE with an onset date on or after the date of informed consent until 28 days after discontinuation of drug. AEs included both serious AEs (SAEs) and all non-SAEs. An SAE was an AE or suspected adverse reaction that, at any dose, in the view of the either the investigator or sponsor, resulted in any of the followi

Interventions

  • DRUG Voxelotor

Trial Details

FieldValue
Enrollment Target 162 participants
Start Date 2019-11-18
Est. Completion 2024-11-01
Phase Phase 3
Pfizer

1,845 total trials

Why NCT04188509 stopped before completion

NCT04188509 is an interventional study that assigns participants to a tested intervention. The registered 162 participants enrollment target is mid-sized for trials with a published cap, below the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (79% lower).

The record links to 0 conditions, and to 1 intervention - of which Voxelotor is the first listed.

NCT04188509 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT04188509 about?

NCT04188509 is a clinical study titled "Open-Label Extension of Voxelotor". Open-label extension study of voxelotor for participants with Sickle Cell Disease who have participated in voxelotor clinical trials.

What is the current status of trial NCT04188509?

This trial is currently terminated. It is a Phase 3 study. The enrollment target is 162 participants. The study started on 2019-11-18. Estimated completion is 2024-11-01.

What interventions are being tested in trial NCT04188509?

The interventions under investigation include: Voxelotor (DRUG).

Who is sponsoring clinical trial NCT04188509?

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

How this trial's enrollment target compares

Where NCT04188509's enrollment target sits among peer trials

162 1474th of 2000 higher than 523 of 2,000 other Phase 3 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phase 3 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 NCT04188509, the US trial registry maintained by the National Library of Medicine. NCT04188509 (mid enrollment · none site footprint · terminated) retrieved and formatted by PlainTrial, see methodology.