Gabapentin Enacarbil (GSK1838262) Adult Restless Leg Syndrome (RLS) Post Marketing Commitment Study
Condition: Restless Legs Syndrome
MeSH terms: Psychomotor Agitation; Restless Legs Syndrome; Syndrome
Intervention: GSK1838262 600 mg; GSK1838262 450 mg; GSK1838262 300 mg; GSK1838262 Placebo match
Intervention description: Drug: GSK1838262 600 mg/day Comparison of 3 doses; Drug: GSK1838262 450 mg/day Comparison of 3 doses; Drug: GSK1838262 300 mg/day Comparison of 3 doses; Drug; GSK1838262 placebo to match 600 mg, 450 mg, 300 mg doses
Intervention MeSH terms: Gabapentin
Phase: Phase 4
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Enrollment: 501.0
Sex: All
Minimum age: 18 Years
Healthy volunteers: No
Keywords: gabapentin enacarbil; Horizant

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).
    

Eligibility criteria:

        Inclusion Criteria:

          -  Men or women 18 years of age or older

          -  History of RLS symptoms for at least 15 nights/month

          -  Documented RLS symptoms, using the 7-day RLS Symptom Record, for at least 4 of the 7
             consecutive evenings/nights during the night

          -  Total RLS severity score of 15 or greater on the International RLS (IRLS) Rating Scale
             at Visit 1 and at Visit 2

          -  Discontinuation of dopamine agonists and/or gabapentin , or other treatments for RLS
             (e.g. opioids, benzodiazepines) at least 2 weeks prior to Baseline

          -  If taking any prescription medication, therapy must have been stabilized for at least
             3 months prior to Screening with no anticipated changes for the duration of the study

          -  Female subjects are eligible if of non-childbearing potential or not lactating, has a
             negative pregnancy, and agrees to use a highly effective method for avoiding pregnancy

          -  Body mass index of 34 or below

          -  Estimated creatinine clearance of ≥60 mL/min

          -  Provides written consent in accordance with all applicable regulatory requirements

        Exclusion Criteria:

          -  History of a sleep disorder that may affect the assessment of RLS

          -  History of RLS symptom augmentation or end-of-dose rebound with previous dopamine
             agonist treatment

          -  Neurologic disease or movement disorder

          -  Other medical conditions or drug therapy that could affect RLS efficacy assessments or
             may present a safety concern

          -  Have clinically significant or unstable medical conditions

          -  Have active suicidal plan/intent or has had active suicidal thoughts in the past 6
             months; has a history of suicide attempt