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NCT01668667 · ClinicalTrials.gov registry record · Phase 4

Gabapentin Enacarbil (GSK1838262) Adult Restless Leg Syndrome (RLS) Post Marketing Commitment Study

A Phase 4 study, sponsored by XenoPort.

Completed
Registry status
Phase 4
Development phase
501
Enrollment target

NCT01668667: Completed Phase 4 study, sponsored by XenoPort.

NCT01668667 is a Phase 4 study that has completed, run by XenoPort. The registered enrollment target is 501 participants, roughly in line with the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT01668667, a Phase 4 study, has completed, sponsored by XenoPort.

COMPLETED
Registry status
Phase 4
Development phase
501 participants
Enrollment target

Study Summary

Gabapentin enacarbil (GEn; GSK1838262; HORIZANT), at a dose of 600 mg/day, is currently approved in the United States for the treatment of adults with moderate-to-severe primary Restless Legs Syndrome (RLS). The aim of this study is to compare the efficacy, tolerability, and safety of GEn at lower doses (450 and 300 mg/day) as well as the already approved dose of 600 mg/day versus placebo for the treatment of subjects with moderate to severe primary RLS. This study is being conducted as a post-marketing commitment (PMC) as a condition of the approval of HORIZANT tablets (NDA 022399).

Primary Outcome

International Restless Legs Syndrome Rating Scale: Very severe=31-40, Severe=21-30, Moderate=11-20, Mild=1-10, None=0. Change from Baseline = LOCF value at current visit - value at Baseline (the last nonmissing assessment before the first dose of study medication). A negative treatment difference indicates a benefit relative to placebo. The change from baseline data is analyzed using an ANCOVA model with treatment and pooled site as the main effects and the baseline IRLS Rating Scale total sco

Interventions

  • DRUG GSK1838262 600 mg
  • DRUG GSK1838262 450 mg
  • DRUG GSK1838262 300 mg
  • DRUG GSK1838262 Placebo match

Trial Details

FieldValue
Enrollment Target 501 participants
Start Date 2012-06
Est. Completion 2013-11
Phase Phase 4
XenoPort

19 total trials

What the finished NCT01668667 record still lists

NCT01668667 is an interventional study that assigns participants to a tested intervention. The registered 501 participants enrollment target is mid-sized for trials with a published cap, roughly in line with the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target.

The record links to 0 conditions, and to 4 interventions - of which GSK1838262 600 mg is the first listed.

NCT01668667 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT01668667 about?

NCT01668667 is a clinical study titled "Gabapentin Enacarbil (GSK1838262) Adult Restless Leg Syndrome (RLS) Post Marketing Commitment Study". Gabapentin enacarbil (GEn; GSK1838262; HORIZANT), at a dose of 600 mg/day, is currently approved in the United States for the treatment of adults with moderate-to-severe primary Restless Legs Syndrome (RLS). The aim of this study is to compare the efficacy, tolerability, and safety of GEn at lower d...

What is the current status of trial NCT01668667?

This trial is currently completed. It is a Phase 4 study. The enrollment target is 501 participants. The study started on 2012-06. Estimated completion is 2013-11.

What interventions are being tested in trial NCT01668667?

The interventions under investigation include: GSK1838262 600 mg (DRUG), GSK1838262 450 mg (DRUG), GSK1838262 300 mg (DRUG), GSK1838262 Placebo match (DRUG).

Who is sponsoring clinical trial NCT01668667?

This trial is sponsored by XenoPort, which has 19 total clinical trials registered on ClinicalTrials.gov.

How this trial's enrollment target compares

Where NCT01668667's enrollment target sits among peer trials

501 164th of 2000 higher than 1,836 of 2,000 other Phase 4 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phase 4 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 NCT01668667, the US trial registry maintained by the National Library of Medicine. NCT01668667 (mid enrollment · none site footprint · completed) retrieved and formatted by PlainTrial, see methodology.