| Unknown | An Efficacy and Safety Evaluation of HORIZANT in Adolescents With Moderate-to-Severe Primary RLS RLS | Phase 4 | 2016-02-01 |
| Withdrawn | A PK and Safety Evaluation of HORIZANT (Gabapentin Enacarbil) in Adolescents With Moderate-to-Severe Primary R RLS | Phase 1 | 2016-01-01 |
| Unknown | An Extension Study to Evaluate the Efficacy and Safety of HORIZANT in Adolescents With Moderate-to-Severe Prim RLS | Phase 4 | 2016-01-01 |
| Completed | Gabapentin Enacarbil (GSK1838262) Adult Restless Leg Syndrome (RLS) Post Marketing Commitment Study Restless Legs Syndrome | Phase 4 | 2012-06-01 |
| Completed | A Study to Evaluate the Effect of Gabapentin on Cardiac Repolarization in Healthy Volunteers Restless Legs Syndrome | Phase 1 | 2012-01-01 |
| Completed | Drug Drug Interaction Study With Gabapentin Enacarbil and Morphine Restless Legs Syndrome | Phase 1 | 2011-08-01 |
| Completed | Study to Assess the Effect of Gabapentin Enacarbil on Simulated Driving in Healthy Subjects Restless Legs Syndrome (RLS) | Phase 1 | 2011-06-01 |
| Completed | Efficacy and Safety of Arbaclofen Placarbil in Subjects With Spasticity Due to Multiple Sclerosis Multiple Sclerosis | Phase 3 | 2011-05-01 |
| Completed | A Efficacy, Safety and Pharmacokinetic Study of XP21279 and Sinemet® in Parkinson's Disease Subjects Parkinson's Disease | Phase 2 | 2010-07-01 |
| Completed | A Study to Evaluate the Efficacy and Safety of Arbaclofen Placarbil (XP19986) as Adjunctive Therapy in Subject Gastroesophageal Reflux Disease | Phase 2 | 2009-09-01 |
| Completed | An Exploratory Study of XP21279 (With Lodosyn®) and Sinemet® in Parkinson's Disease Subjects Parkinson's Disease | Phase 1 / Phase 2 | 2009-05-01 |
| Completed | Relative Bioavailability Study for GSK1838262 (Gabapentin Enacarbil) Pharmacokinetics, Healthy Volunteer | Phase 1 | 2009-01-01 |
| Completed | A Study to Evaluate the Safety and Tolerability of Arbaclofen Placarbil (XP19986) in Subjects With Acute Back Back Pain | Phase 2 | 2008-12-01 |
| Completed | Polysomnography Study of GSK1838262 Extended Release Tablets Versus Placebo in RLS and Associated Sleep Distur Restless Legs Syndrome, Restless Legs Syndrome (RLS) | Phase 3 | 2008-10-01 |
| Completed | Prevention Study in Adult Patients Suffering From Migraine Headaches Migraine Disorders, Migraine | Phase 2 | 2008-08-01 |
| Completed | A Study In Patients With Neuropathic Pain From Diabetic Peripheral Neuropathy (DPN) Neuropathy, Diabetic | Phase 2 | 2008-03-01 |
| Completed | A Clinical Study in Subjects With Neuropathic Pain From PHN Who Have Had an Inadequate Response to Gabapentin Neuralgia, Postherpetic | Phase 2 | 2008-03-01 |
| Completed | A Study In Patients With Neuropathic Pain From Post-Herpetic Neuralgia (PHN) Neuralgia, Postherpetic | Phase 2 | 2008-02-01 |
| Completed | A Safety and Efficacy Study of XP19986 in Subjects With Spasticity Due to Spinal Cord Injury Muscle Spasticity | Phase 2 | 2007-12-01 |
| Completed | An Efficacy and Safety Study of XP19986 in Subjects With Symptomatic GERD Gastroesophageal Reflux | Phase 2 | 2007-11-01 |
| Completed | Simulated Driving Study in Restless Legs Syndrome Restless Legs Syndrome | Phase 2 | 2007-04-01 |
| Completed | Dose-Response and Pharmacokinetics of Gabapentin Enacarbil (GEn [XP13512 / GSK1838262]) in Restless Legs Syndr Restless Legs Syndrome | Phase 2 | 2007-01-01 |
| Completed | XP13512 vs. Placebo in Patients With Restless Legs Syndrome. Restless Legs Syndrome | Phase 3 | 2006-08-01 |
| Completed | XP13512 (Gabapentin Enacarbil) Extension Study in Patients With Restless Legs Syndrome. Restless Legs Syndrome | Phase 3 | 2006-06-01 |
| Completed | Long-Term Study of Gabapentin Enacarbil (GEn, XP13512) vs. Placebo in Patients With Restless Legs Syndrome. Restless Legs Syndrome | Phase 3 | 2006-04-01 |
| Completed | XP13512 (GSK1838262) Versus Placebo in Patients With Restless Legs Syndrome. Restless Legs Syndrome | Phase 3 | 2006-03-01 |