Clinical trial NCT00310375: Open-label Extension Study of the Phase 3 VRX-RET-E22-301 Double-Blind Trial
Official title: A Multicenter, Open-label, Long-term, Safety, Tolerability and Efficacy Study of Retigabine in Adult Epilepsy Patients With Partial-onset Seizures (Extension of Study VRX-RET-E22-301)
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE3
Conditions: Epilepsy
Keywords: Epilepsy
Partial Seizures
Potassium Channels
Anticonvulsant
Complex Partial Seizures
Epilepsies, Partial
RTG115098
Lead sponsor: GlaxoSmithKline
Sponsor class: INDUSTRY
First posted: 2006-04-03
Enrollment: 181
Sex: ALL
Minimum age (years): 18
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to evaluate the safety and tolerability of long-term therapy with retigabine administered as adjunctive therapy in adult epilepsy patients with partial-onset seizures, who completed the VRX-RET-E22-301 double-blind study. The efficacy of long-term treatment with retigabine and patient quality of life will also be assessed.

Detailed description: This Phase 3 trial is an open-label extension study of the placebo-controlled, double-blind VRX-RET-E22-301 trial. Patients who have completed the VRX-RET-E22-301 trial and who meet inclusion and exclusion criteria will be treated with 600-1200 mg/day of retigabine as an adjunct therapy to their current antiepileptic drugs (AEDs) or vagal nerve stimulation. Treatment will be continued until retigabine is commercially available, or until the program is discontinued. Patients will be recruited from 45-50 sites in the United States, Canada, Mexico, Brazil, and Argentina. The safety and tolerability of long-term therapy with retigabine administered as adjunctive therapy in adult epilepsy patients with partial-onset seizures will be evaluated. In addition, the efficacy of long-term treatment with retigabine and patient quality of life will be assessed.

Eligibility criteria: Inclusion Criteria:

* Patient has successfully completed the Maintenance and Transition phases of Study VRX-RET-E22-301 for the treatment of partial-onset seizures
* Patient is expected to benefit from participation in the study in the opinion of the Investigator.

Exclusion Criteria:

* Patient meets any of the withdrawal criteria in the previous VRX-RET-E22-301 study or is experiencing an ongoing serious adverse event.
* Patient is receiving any investigational drug or using any experimental device in addition to Retigabine for treatment of epilepsy or any other medical condition.
* Patient has any other condition that would prevent compliance with the study procedures or proper reporting of adverse events.

Primary outcomes:
measure: Number of Participants With Treatment-emergent Serious Adverse Event (SAE) and Adverse Event (AE)
timeFrame: Assessed up to a maximum of 9 years
measure: Number of Participants With Treatment-emergent Adverse Events Leading to Withdrawal From Study Drug
timeFrame: Assessed up to a maximum of 9 years
measure: Kaplan-Meier Estimate of the Probability of Discontinuation (d/c) From Study Drug
timeFrame: Assessed up to a maximum of 9 years
measure: Change From Baseline in Blood Pressure
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Heart Rate
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Body Temperature
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Weight
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in the 12-lead Electrocardiogram (ECG) Parameters-PR Interval, QRS Duration, Uncorrected QT (uQT) Interval, Corrected QT (Bazett's Correction) Interval (QTcB), Corrected QT (Friedericia's Correction) Interval (QTcF)
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in the 12-lead Electrocardiogram (ECG) Parameter-RR Interval
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Electrocardiogram (ECG) Parameter-QRS Axis
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Hematology Parameters- Bands, Basophils, Eosinophils, Lymphocytes, Metamyelocyte, Monocytes, Neutrophils, Platelets, White Blood Cells Count (WBC)
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Hematology Parameter-Red Blood Cell Count
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Haematocrit
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Haemoglobin
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Chemistry Parameters-Alkaline Phosphatase (AP), Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST)
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Chemistry Parameters-Bicarbonate, Blood Urea Nitrogen (BUN), Calcium, Chloride, Cholesterol, Non-fasting Glucose, Phosphorus, Potassium, Sodium, Urea
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Chemistry Parameters -Creatinine, Total Bilirubin (TB), Uric Acid (UA)
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Chemistry Parameter-Total Protein
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Urine Specific Gravity
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Urine Power of Hydrogen (pH)
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Post-void Residual Bladder Ultrasound Volume
timeFrame: Baseline and Up to Month 108
measure: Change From Baseline in Overall American Urological Association (AUA) Symptom Index Score
timeFrame: Baseline and Up to Month 108
measure: Number of Participants With Abnormal Results in Physical Examination
timeFrame: Up to Month 108
measure: Number of Participants With Abnormal Results of Neurological Examination
timeFrame: Up to Month 108
measure: Number of Participants With Pigmentation of Non-retinal Ocular Tissue
timeFrame: Assessed up to a maximum of 9 years
measure: Number of Participants With Pigmentation of Retinal Ocular Tissue
timeFrame: Assessed up to a maximum of 9 years
measure: Number of Participants With Abnormal Pigmentation of Skin, Including the Skin Around the Eyes and the Eyelids, Lips, Nails, or Mucosa
timeFrame: Assessed up to a maximum of 9 years
measure: Number of Participants With a Clinically Significant Decrease in Visual Acuity From Initial Examination
timeFrame: Assessed up to a maximum of 9 years
measure: Number of Participants With a Decrease in Confrontational Visual Field From Initial Examination
timeFrame: Assessed up to a maximum of 9 years
measure: Number of Participants With Resolution of Abnormal Eye Pigmentation After Discontinuation of Retigabine
timeFrame: 2 years and 9 months
measure: Number of Participants With Resolution of Dermatologist Confirmed Abnormal Discoloration After Discontinuation of Retigabine
timeFrame: 2 years 9 months
measure: Time From Discontinuation of Retigabine to Resolution of Abnormal Eye Pigmentation
timeFrame: 2 years 9 months
measure: Time From Discontinuation of Retigabine to Resolution of All Dermatologist-Confirmed Abnormal Discoloration
timeFrame: 2 years 9 months
Secondary outcomes:
measure: Percentage Change From Baseline in the 28-day Partial Seizure
timeFrame: Assessed up to a maximum of 9 years
measure: Number of Responders
timeFrame: Assessed up to a maximum of 9 years
measure: Number of Participants Who Were Seizure Free for Any 6 Continuous Months
timeFrame: Assessed up to a maximum of 9 years
measure: Number of Participants Who Were Seizure Free for Any 12 Continuous Months
timeFrame: Assessed up to a maximum of 9 years
measure: Percentage of Seizure-free Days
timeFrame: Assessed up to a maximum of 9 years
measure: Change From Baseline in Quality of Life in Epilepsy (QOLIE)-31-P Questionnaire
timeFrame: Assessed up to a maximum of 9 years
Other outcomes:
Locations:
city: Birmingham
country: United States
facility: University of Alabama -- Department of Neurology/Epilepsy Center
state: Alabama
city: Huntsville
country: United States
facility: North Alabama Neuroscience Research Associates
state: Alabama
city: Northport
country: United States
facility: Neurology Clinic
state: Alabama
city: Phoenix
country: United States
facility: Barrow Neurological Institute
state: Arizona
city: Little Rock
country: United States
facility: Clinical Trials Inc.
state: Arkansas
city: La Jolla
country: United States
facility: UCSD Thornton Hospital
state: California
city: Los Angeles
country: United States
facility: University of Southern California -- Keck School of Medicine
state: California
city: Los Angeles
country: United States
facility: West Los Angeles VA Healthcare Center
state: California
city: Colorado Springs
country: United States
facility: Delta Waves
state: Colorado
city: Denver
country: United States
facility: University of Colorado Department Of Neurology
state: Colorado
city: Jacksonville
country: United States
facility: University of Florida -- Shands Jacksonville
state: Florida
city: Miami
country: United States
facility: University of Miami
state: Florida
city: Sarasota
country: United States
facility: Lovelace Scientific Resources
state: Florida
city: Ames
country: United States
facility: McFarland Clinic
state: Iowa
city: Lexington
country: United States
facility: University of Kentucky
state: Kentucky
city: Bethesda
country: United States
facility: Mid-Atlantic Epilepsy and Sleep Center
state: Maryland
city: Detroit
country: United States
facility: Henry Ford Hospital
state: Michigan
city: Saint Paul
country: United States
facility: Minnesota Epilepsy Group, P.A.
state: Minnesota
city: Chesterfield
country: United States
facility: The Comprehensive Epilepsy Care Center for Children and Adults
state: Missouri
city: New York
country: United States
facility: Beth Israel Medical Center
state: New York
city: Asheville
country: United States
facility: Asheville Neurology Specialists
state: North Carolina
city: Toledo
country: United States
facility: Medical University of Ohio at Toledo
state: Ohio
city: Tualatin
country: United States
facility: Oregon Neurology PC
state: Oregon
city: Hershey
country: United States
facility: Milton S. Hershey Medical Center
state: Pennsylvania
city: Nashville
country: United States
facility: Vanderbilt University Medical Center
state: Tennessee
city: Dallas
country: United States
facility: Medical City Dallas Hospital
state: Texas
city: Dallas
country: United States
facility: Neurological Clinic of Texas
state: Texas
city: Houston
country: United States
facility: Memorial Hermann Hospital
state: Texas
city: Charlottesville
country: United States
facility: University of Virginia Comprehensive Epilepsy Program
state: Virginia
city: Richmond
country: United States
facility: Virginia Commonwealth University Medical Center
state: Virginia
city: Capital Federal
country: Argentina
facility: Hospital Italiano de Buenos Aires
state: CBA
city: Capital Federal
country: Argentina
facility: Hospital General de Agudos "Dr. J.M. Ramos Mejia"
state: CBA
city: Capital Federal
country: Argentina
facility: Hospital General de Agudos "Dr. Teodoro Alvarez"
state: CBA
city: Cordoba
country: Argentina
facility: Fundacion Lennox
state: CRD
city: Cordoba
country: Argentina
facility: Sanatorio del Salvador II
state: CRD
city: Cordoba
country: Argentina
facility: Hospital Privado Centro Medico de Cordoba
state: CRD
city: Salvador
country: Brazil
facility: Hospital Universitario Prof Edgard Santos -- UFBA
state: BA
city: Ribeirao Preto
country: Brazil
facility: Hospital das Clinicas de Ribeirao Preto -- Universidade de Sa Neurologia
state: SP
city: Sao Paulo
country: Brazil
facility: Hospital Sao Paulo -- Escola Paulista de Medicina -- UNIFESP
state: SP
city: Sao Paulo
country: Brazil
facility: Hospital das Clinicas da Fac de Medicina de Sao Paulo
state: SP
city: Calgary
country: Canada
facility: Foothills Medical Center
state: Alberta
city: Edmonton
country: Canada
facility: Glenrose Rehabilitation Center
state: Alberta
city: St. John's
country: Canada
facility: Health Sciences Centre
state: Newfoundland and Labrador
city: Montréal
country: Canada
facility: CHUM -- Hôpital Notre-Dame
state: Quebec
city: La Fama
country: Mexico
facility: Instituto Nacional de Neurologia y Neurocirugia
state: DF
city: Mexico
country: Mexico
facility: Centro Medico
state: DF
city: Mexico
country: Mexico
facility: Hospital de Psiquiatria San Fernando, IMSS
state: DF
city: Tlalpan
country: Mexico
facility: CIF BIOTEC, Medica Sur
state: DF
city: Guadalajara
country: Mexico
facility: Antiguo Hospital Civil de Guadalajara
state: Jalisco
city: Monterrey
country: Mexico
facility: Hospital y Clinica OCA S.A. de C.V.
state: Nuevo Leon
city: San Luis Potosi
country: Mexico
facility: Hospital Central Dr. Ignacio Morones Prieto
state: SLP
Study officials:
affiliation: GlaxoSmithKline
name: GSK Clinical Trials
role: STUDY_DIRECTOR
References: