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 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).