EpilepsyPhase 3NCT00310375
Open-label Extension Study of the Phase 3 VRX-RET-E22-301 Double-Blind Trial
A Phase 3 study testing Ezogabine: USAN Retigabine (International Nonproprietary Name) in people with Epilepsy, run by GlaxoSmithKline at 51 sites in 5 countries.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 75 years
- Conditions the study is for
- Epilepsy
- What is being tested?
- Ezogabine: USAN Retigabine (International Nonproprietary Name)
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 181 participants
- Where
- 51 sitesin 5 countries
- Study dates
- 1 May 2006to 15 Mar 2017
- Phase
- Phase 3
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 75 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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.
Who cannot join
- 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.
Trial locations and contacts
51 sites in 5 countries.
51 sites in 5 countries
United States30 sites
McFarland Clinic
Ames, Iowa, 50010
Asheville Neurology Specialists
Asheville, North Carolina, 28801
Mid-Atlantic Epilepsy and Sleep Center
Bethesda, Maryland, 20817
University of Alabama -- Department of Neurology/Epilepsy Center
Birmingham, Alabama, 35294
University of Virginia Comprehensive Epilepsy Program
Charlottesville, Virginia, 22903
The Comprehensive Epilepsy Care Center for Children and Adults
Chesterfield, Missouri, 63017
Delta Waves
Colorado Springs, Colorado, 80918
Medical City Dallas Hospital
Dallas, Texas, 75230
Neurological Clinic of Texas
Dallas, Texas, 75230
University of Colorado Department Of Neurology
Denver, Colorado, 80010
Henry Ford Hospital
Detroit, Michigan, 48202
Milton S. Hershey Medical Center
Hershey, Pennsylvania, 17033
Memorial Hermann Hospital
Houston, Texas, 77030
North Alabama Neuroscience Research Associates
Huntsville, Alabama, 35801
University of Florida -- Shands Jacksonville
Jacksonville, Florida, 32209
UCSD Thornton Hospital
La Jolla, California, 92037
University of Kentucky
Lexington, Kentucky, 40536
Clinical Trials Inc.
Little Rock, Arkansas, 72205
University of Southern California -- Keck School of Medicine
Los Angeles, California, 90033
West Los Angeles VA Healthcare Center
Los Angeles, California, 90073
University of Miami
Miami, Florida, 33136
Vanderbilt University Medical Center
Nashville, Tennessee, 37212
Beth Israel Medical Center
New York, New York, 10003
Neurology Clinic
Northport, Alabama, 35476
Barrow Neurological Institute
Phoenix, Arizona, 85013
Virginia Commonwealth University Medical Center
Richmond, Virginia, 23298
Minnesota Epilepsy Group, P.A.
Saint Paul, Minnesota, 55102
Lovelace Scientific Resources
Sarasota, Florida, 34233
Medical University of Ohio at Toledo
Toledo, Ohio, 43614
Oregon Neurology PC
Tualatin, Oregon, 97062
Mexico7 sites
Antiguo Hospital Civil de Guadalajara
Guadalajara, Jalisco, 44280
Instituto Nacional de Neurologia y Neurocirugia
La Fama, Mexico City, 42690
Centro Medico
Mexico City, Mexico City, 03229
Hospital de Psiquiatria San Fernando, IMSS
Mexico City, Mexico City, 14050
Hospital y Clinica OCA S.A. de C.V.
Monterrey, Nuevo León, 64000
Hospital Central Dr. Ignacio Morones Prieto
San Luis Potosí City, San Luis Potosí, 78250
CIF BIOTEC, Medica Sur
Tlalpan, Mexico City, 14050
Argentina6 sites
Hospital Italiano de Buenos Aires
Capital Federal, CBA, C1181ACH
Hospital General de Agudos "Dr. J.M. Ramos Mejia"
Capital Federal, CBA
Hospital General de Agudos "Dr. Teodoro Alvarez"
Capital Federal, CBA
Fundacion Lennox
Córdoba, CRD, 5000
Sanatorio del Salvador II
Córdoba, CRD, 5000
Hospital Privado Centro Medico de Cordoba
Córdoba, CRD, X5016KEH
Brazil4 sites
Hospital das Clinicas de Ribeirao Preto -- Universidade de Sa Neurologia
Ribeirão Preto, São Paulo, 14048-900
Hospital Universitario Prof Edgard Santos -- UFBA
Salvador, Estado de Bahia, 40110-060
Hospital Sao Paulo -- Escola Paulista de Medicina -- UNIFESP
São Paulo, São Paulo, 04024 002
Hospital das Clinicas da Fac de Medicina de Sao Paulo
São Paulo, São Paulo, 05403-900
Canada4 sites
Foothills Medical Center
Calgary, Alberta, T2N 2T9
Glenrose Rehabilitation Center
Edmonton, Alberta, T5G 0B7
CHUM -- Hôpital Notre-Dame
Montreal, Quebec, H2L 4M1
Health Sciences Centre
St. John's, Newfoundland and Labrador, A1B 3V6
About this study
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)
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.
Read the 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.
- Conditions
- Epilepsy
- Being tested
- Ezogabine: USAN Retigabine (International Nonproprietary Name)
- Keywords
- Epilepsy, Partial Seizures, Potassium Channels, Anticonvulsant, Complex Partial Seizures, Epilepsies, Partial, RTG115098
- Medical subject headings
- Epilepsy, Seizures, Epilepsies, Partial
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Ezogabine: USAN Retigabine (International Nonproprietary Name)Drug
Also called GKE-841, D-23129, GW582892X
Film-coated tablets containing 50 mg, 100 mg, or 300 mg of retigabine per tablet. Dosage and frequency will be specific to each patient so long as the patient receives between 600 and 1200 mg of retigabine per day. The duration will be until the trial concludes or the patient leaves the trial.
| Study group | Role | What they receive |
|---|---|---|
| Ezogabine: USAN Retigabine (International Nonproprietary Name) | Experimental | Film-coated tablets - 50mg, 100mg or 300mg Receives: Drug: Ezogabine: USAN Retigabine (International Nonproprietary Name) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of Participants With Treatment-emergent Serious Adverse Event (SAE) and Adverse Event (AE)
An AE is any untoward medical occurrence in a clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. An SAE is any untoward medical occurrence that, at any dose results in death, is life-threatening, requires hospitalization (unplanned hospital stay) or prolongation of existing hospitalization, results in disability/incapacity or is a congenital anomaly/birth defect. Treatment-emergent AE was defined as an AE with an onset on or after the day of first dose of the study medication and on or before 30 days after the last dose date. AEs reported during parent study and worsened after first dose of RTG in this OLE study were also reported.
Measured: Assessed up to a maximum of 9 years
Number of Participants With Treatment-emergent Adverse Events Leading to Withdrawal From Study Drug
Treatment-emergent AE was defined as an AE with an onset on or after the day of first dose of the study medication and on or before 30 days after the last dose date. AEs reported during parent study and worsened after first dose of RTG in this OLE study were also reported.
Measured: Assessed up to a maximum of 9 years
Kaplan-Meier Estimate of the Probability of Discontinuation (d/c) From Study Drug
The time frame of premature study discontinuation was defined as the time from the day of first the study medication to the time of withdrawal from study drug. For those who have a taper dose start date, the time of withdrawal was the day before the start of taper dose. For those without a taper dose start date, the time of withdrawal was the last dose date. Participants who switched to the commercial product were censored at the last dose of study drug in the Kaplan-Meier analysis. All participants who withdrew from study drug prematurely but didn't switch to commercial product were counted as "events". Kaplan-Meier estimate of the probability of discontinuation at the specified time or earlier. Number of Participants continuing on RTG at each time of withdrawal were analyzed (represented as n=X in category title).
Measured: Assessed up to a maximum of 9 years
Change From Baseline in Blood Pressure
Systolic blood pressure (SBP) and diastolic blood pressure (DBP) was obtained in supine (Su) position and again in standing (St) position after the participant was standing for approximately 2 minutes at each study visit (Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). Not Applicable (NA) indicates that data were not available.
Measured: Baseline and Up to Month 108
Change From Baseline in Heart Rate
Heart rate (HR) was measured in supine (Su) position and again in standing (St) position after the participant was standing for approximately 2 minutes at each study visit (Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Measured: Baseline and Up to Month 108
Change From Baseline in Body Temperature
Body temperature was measured in degree Celsius at each study visit (Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available
Measured: Baseline and Up to Month 108
Change From Baseline in Weight
Weight was measured in ordinary indoor clothing (without shoes) and was recorded at each study visit (On Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Measured: Baseline and Up to Month 108
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)
A 12-lead ECG was performed at each study visit during the first year of the study (Month 1, Month 3, Month 6, Month 9, Month 12) and annually after one year. The following electrocardiogram parameters are presented PR Interval, QRS Duration, Uncorrected QT interval (uQT), Corrected QT (Bazett's correction) interval (QTcB), Corrected QT (Friedericia's correction) interval (QTcF). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Measured: Baseline and Up to Month 108
Change From Baseline in the 12-lead Electrocardiogram (ECG) Parameter-RR Interval
A 12-lead ECG was performed at each study visit during the first year of the study (Month 1, Month 3, Month 6, Month 9, Month 12) and annually after one year. The following electrocardiogram parameters are presented: RR Interval. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles).
Measured: Baseline and Up to Month 108
Change From Baseline in Electrocardiogram (ECG) Parameter-QRS Axis
A 12-lead ECG was performed at each study visit during the first year of the study (Month 1, Month 3, Month 6, Month 9, Month 12) and annually after one year. ECG parameter QRS Axis is presented here. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles).
Measured: Baseline and Up to Month 108
Change From Baseline in Hematology Parameters- Bands, Basophils, Eosinophils, Lymphocytes, Metamyelocyte, Monocytes, Neutrophils, Platelets, White Blood Cells Count (WBC)
Following hematology parameters were assessed, Bands (Band neutrophils), Basophils, Eosinophils, Lymphocytes, Metamyelocyte, Monocytes, Neutrophils, Platelets and WBC. Hematology parameters were assessed at Month 1, Month 2, Month 3, Month 6, Month 8, Month 9, Month 10, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Measured: Baseline and Up to Month 108
Change From Baseline in Hematology Parameter-Red Blood Cell Count
Red Blood Cell count (RBC) was assessed at Month 1, Month 2, Month 3, Month 6, Month 8, Month 9, Month 10, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available..
Measured: Baseline and Up to Month 108
Change From Baseline in Haematocrit
Haematocrit was assessed at Month 1, Month 2, Month 3, Month 6, Month 8, Month 9, Month 10, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles).
Measured: Baseline and Up to Month 108
Change From Baseline in Haemoglobin
Haemoglobin was assessed at Month 1, Month 2, Month 3, , Month 6, Month 8, Month 9, Month 10, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available..
Measured: Baseline and Up to Month 108
Change From Baseline in Chemistry Parameters-Alkaline Phosphatase (AP), Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST)
Alkaline phosphatase (AP), Alanine aminotransferase (ALT), Aspartate aminotransferase (AST) were assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Measured: Baseline and Up to Month 108
Change From Baseline in Chemistry Parameters-Bicarbonate, Blood Urea Nitrogen (BUN), Calcium, Chloride, Cholesterol, Non-fasting Glucose, Phosphorus, Potassium, Sodium, Urea
Bicarbonate (Bic.), BUN, Calcium (Ca), Chloride (Cl), Cholesterol (Cho.), Non-fasting glucose (NFG), Phosphorus (P), Potassium (Ka), Sodium (Na), Urea were assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Measured: Baseline and Up to Month 108
Change From Baseline in Chemistry Parameters -Creatinine, Total Bilirubin (TB), Uric Acid (UA)
Creatinine, Total bilirubin (TB), Uric acid (UA) were assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Measured: Baseline and Up to Month 108
Change From Baseline in Chemistry Parameter-Total Protein
Total Protein (TP) was assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles)
Measured: Baseline and Up to Month 108
Change From Baseline in Urine Specific Gravity
Urine Specific gravity (USG) was assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Measured: Baseline and Up to Month 108
Change From Baseline in Urine Power of Hydrogen (pH)
Urine pH was assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Measured: Baseline and Up to Month 108
Change From Baseline in Post-void Residual Bladder Ultrasound Volume
Post-void residual (PVR) bladder was assessed using ultrasound scan to assess urinary retention at Month 1, Month 3, Month 12 and annually after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles)
Measured: Baseline and Up to Month 108
Change From Baseline in Overall American Urological Association (AUA) Symptom Index Score
An AUA Symptom Index is a 7-item Likert-scored scale describing urinary bladder function and was completed by the Investigator to assess the participant's urinary voiding function at Month 1, Month 3, Month 12 and annually after Month 12. The index scale ranges from 0-35, where higher scores are indicative of a worse issue. Scores are categorized as 0-7 mild, 8-19 moderate and >19 severe. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles)
Measured: Baseline and Up to Month 108
Number of Participants With Abnormal Results in Physical Examination
A complete physical examination was performed at the end of each 12 month study cycle. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). If a participant had an abnormal result for at least one body system of exam, that participant was included in the 'Abnormal' category
Measured: Up to Month 108
Number of Participants With Abnormal Results of Neurological Examination
Participants were assessed at Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12. Participants in the worst category among the results of all neurological examination parameters are presented. Abnormal results were categorised as Abnormal not Clinically Significant (AbNCS)and Abnormal and Clinically Significant (AbCS). Only those participants available at the specified time points were analyzed (represented by n=X in the category titles)
Measured: Up to Month 108
Number of Participants With Pigmentation of Non-retinal Ocular Tissue
The ophthalmologist/retina specialist determined the presence or absence of abnormal discoloration of all non-retinal ocular tissues. Only those participants available at the specified time points were analyzed.
Measured: Assessed up to a maximum of 9 years
Number of Participants With Pigmentation of Retinal Ocular Tissue
The ophthalmologist/retina specialist determined the presence or absence of abnormal discoloration of retinal ocular tissues. It included Pigmentary abnormalities in the macula, of peripheral retina as well as in both of them.. Only those participants available at the specified time points were analyzed.
Measured: Assessed up to a maximum of 9 years
Number of Participants With Abnormal Pigmentation of Skin, Including the Skin Around the Eyes and the Eyelids, Lips, Nails, or Mucosa
An assessment of the participant's nails, lips, skin and mucosa was completed by the investigator at the 4 monthly study visits. The assessment of the participant's skin included assessment of the skin around the eyes and the eyelids,lips, nails, and mucosa
Measured: Assessed up to a maximum of 9 years
Number of Participants With a Clinically Significant Decrease in Visual Acuity From Initial Examination
A comprehensive eye examination was conducted by retina specialist or general ophthalmologist to assess best corrected visual acuity. An initial comprehensive eye examination was completed by an ophthalmologist for all participants. This exam was not associated with a specific visit. Thereafter, eye examinations was performed approximately every 6 months. Eye examination was introduced following protocol amendment and was conducted in all participants. Participants discontinued before implementation of this amendment and who have not had a comprehensive eye examination and skin examination (and follow-up by a dermatologist, if clinically indicated) were asked to return to the clinic for an evaluation of their skin (and follow-up dermatology examination, if clinically indicated) and for a comprehensive eye examination. Number of Par. with both initial and at least one follow-up exam while on RTG treatment were analyzed.
Measured: Assessed up to a maximum of 9 years
Number of Participants With a Decrease in Confrontational Visual Field From Initial Examination
Decrease in confrontation visual field is defined as a participant having a normal initial exam and an abnormal exam thereafter or, a response of clinically significant worsening in either eye since the last assessment.
Measured: Assessed up to a maximum of 9 years
Number of Participants With Resolution of Abnormal Eye Pigmentation After Discontinuation of Retigabine
The ophthalmologist/retina specialist determined the presence or absence of retinal and non-retinal ocular abnormalities. Retinal abnormalities included abnormalities in the macula and/or the peripheral retina and non-retinal ocular pigmentary abnormality.
Measured: 2 years and 9 months
Number of Participants With Resolution of Dermatologist Confirmed Abnormal Discoloration After Discontinuation of Retigabine
An assessment of the participant's nails, lips, skin and mucosa was completed by the investigator at the 6 monthly SFUCP study visits. The assessment of the participant's skin included assessment of the skin around the eyes and the eyelids, lips, nails, and mucosa.
Measured: 2 years 9 months
Time From Discontinuation of Retigabine to Resolution of Abnormal Eye Pigmentation
Retinal pigmentary abnormality was determined by either an ophthalmologist or retina specialist. Retinal pigmentary abnormality included pigmentary abnormality of macula, pigmentary abnormality of the peripheral retina and non-retinal ocular pigmentary abnormality. If a participant had pigmentary abnormality of macula and pigmentary abnormality of the peripheral retina both should be resolved in order for retinal pigmentary abnormality to be considered resolved. If a participant had non-retinal ocular pigmentary abnormality in more than location (conjunctiva, sclera, cornea, iris or lens), all should be resolved for non-retinal pigmentary abnormality to be considered resolved. Only participants with resolution of the specified pigmentation are included in this analysis.
Measured: 2 years 9 months
Time From Discontinuation of Retigabine to Resolution of All Dermatologist-Confirmed Abnormal Discoloration
Assessments were at approximately 6-monthly intervals (timed relative to the participants previous dermatology assessment) until the abnormal discoloration either resolved or stabilized (as defined by no changes over 2 consecutive 6-monthly assessments performed by the dermatologist over at least 12 months after discontinuation of retigabine). The assessment of the participant's skin included assessment of the skin around the eyes and the eyelids, lips, nails, and mucosa. Only participants with resolution of the specified tissue are included in this analysis.
Measured: 2 years 9 months
Secondary outcomes (6)
Percentage Change From Baseline in the 28-day Partial Seizure
Twenty-eight-day total partial seizure frequency during the study is defined as the sum of total partial seizures from First date (Baseline visit date +1 if no seizures on Baseline or Baseline visit date if seizures reported on the Baseline) to Last date (last visit date for seizure record with non-missing response), divided by applicable days, standardized by 28 days. The applicable days are the days in which the subject had non-missing seizure data. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed.
Measured: Assessed up to a maximum of 9 years
Number of Responders
A participant was classified as a responder if there is an at least 50% reduction from Baseline in the 28-day total Partial Seizure frequency. Baseline was defined as the parent study Baseline. Only those participants available at the specified time points were analyzed.
Measured: Assessed up to a maximum of 9 years
Number of Participants Who Were Seizure Free for Any 6 Continuous Months
Number of seizure free days is defined as the number of applicable days without any seizures (partial, generalized or unclassified). Only the days in which a subject had non-missing seizure data were considered as applicable days. Duration of exposure is defined using a window range allowed for each scheduled visit. At least 6 months of exposure is defined as >= 173 days of exposure since the window range for Month 6 visit is +/- 7 days. Only those participants available at the specified time points were analyzed.
Measured: Assessed up to a maximum of 9 years
Number of Participants Who Were Seizure Free for Any 12 Continuous Months
Duration of exposure is defined using a window range allowed for each scheduled visit. At least 12 months of exposure is defined as >= 353 days of exposure since the window range for Month 12 visit is +/- 7 days. Only those participants available at the specified time points were analyzed.
Measured: Assessed up to a maximum of 9 years
Percentage of Seizure-free Days
Number of seizure free days is defined as the number of applicable days without any seizures (partial, generalized or unclassified). Only the days in which a participant had non-missing seizure data was considered as applicable days
Measured: Assessed up to a maximum of 9 years
Change From Baseline in Quality of Life in Epilepsy (QOLIE)-31-P Questionnaire
The QOLIE-31-P (Version 2.0) was utilized to assess quality of life. The QOLIE-31-P assessment was completed by the participants at Baseline, Month 3, Month 6, Month 9, Month 12 and annually after Month 12. The QOLIE has 7 sub scales as energy fatigue, emotional well being, social functioning, cognitive, medication effects, seizure worry and overall QOL. The assessment range for the overall score and the sub-scales is 0-100, where higher scores indicate greater well being. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles)
Measured: Assessed up to a maximum of 9 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Apr 2006 (estimated)
- Study start1 May 2006
- Primary completion30 Nov 2016
- Study completion15 Mar 2017
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for EpilepsyStudies of the same condition, open and under way.
- More trials run by GlaxoSmithKlineThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 181 participants (actual)
Sponsor and investigators
- Lead sponsor
- GlaxoSmithKline
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- GSK Clinical Trials, Study director, GlaxoSmithKline
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00310375
- Sponsor's protocol ID
- VRX-RET-E22-303
- Other IDs
- RTG115098
- Status last verified
- Jul 2020
- First submitted
- 30 Mar 2006
- Last updated
- 31 Jul 2020
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- Individual data sharing
- Yes: IPD for this study will be made available via the Clinical Study Data Request site.
Study at a glance
From the registry record, last updated by the sponsor on 31 Jul 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- 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)
- ClinicalTrials.gov ID
- NCT00310375
- Acronym / sponsor ID
- VRX-RET-E22-303
- Conditions
- Epilepsy
- Keywords
- Epilepsy, Partial Seizures, Potassium Channels, Anticonvulsant, Complex Partial Seizures, Epilepsies, Partial, RTG115098
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 181 participants (actual)
- Lead sponsor
- GlaxoSmithKlineIndustry (pharma, biotech, devices)
- Study start
- 1 May 2006 (actual)
- Primary completion
- 30 Nov 2016 (actual)
- Study completion
- 15 Mar 2017 (actual)
- First posted
- 3 Apr 2006 (estimated)
- Results
- Posted 25 Nov 2016
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Ezogabine: USAN Retigabine (International Nonproprietary Name) | Experimental | Drug: Ezogabine: USAN Retigabine (International Nonproprietary Name)Film-coated tablets - 50mg, 100mg or 300mg |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- 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.
Key exclusion criteria (3 listed)
- 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Ezogabine: USAN Retigabine (International Nonproprietary Name)Also: GKE-841, D-23129, GW582892XFilm-coated tablets containing 50 mg, 100 mg, or 300 mg of retigabine per tablet. Dosage and frequency will be specific to each patient so long as the patient receives between 600 and 1200 mg of retigabine per day. The duration will be until the trial concludes or the patient leaves the trial. | Drug | Ezogabine: USAN Retigabine (International Nonproprietary Name) |
Primary outcome
Number of Participants With Treatment-emergent Serious Adverse Event (SAE) and Adverse Event (AE)
Time frame: Assessed up to a maximum of 9 years
An AE is any untoward medical occurrence in a clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. An SAE is any untoward medical occurrence that, at any dose results in death, is life-threatening, requires hospitalization (unplanned hospital stay) or prolongation of existing hospitalization, results in disability/incapacity or is a congenital anomaly/birth defect. Treatment-emergent AE was defined as an AE with an onset on or after the day of first dose of the study medication and on or before 30 days after the last dose date. AEs reported during parent study and worsened after first dose of RTG in this OLE study were also reported.
Number of Participants With Treatment-emergent Adverse Events Leading to Withdrawal From Study Drug
Time frame: Assessed up to a maximum of 9 years
Treatment-emergent AE was defined as an AE with an onset on or after the day of first dose of the study medication and on or before 30 days after the last dose date. AEs reported during parent study and worsened after first dose of RTG in this OLE study were also reported.
Kaplan-Meier Estimate of the Probability of Discontinuation (d/c) From Study Drug
Time frame: Assessed up to a maximum of 9 years
The time frame of premature study discontinuation was defined as the time from the day of first the study medication to the time of withdrawal from study drug. For those who have a taper dose start date, the time of withdrawal was the day before the start of taper dose. For those without a taper dose start date, the time of withdrawal was the last dose date. Participants who switched to the commercial product were censored at the last dose of study drug in the Kaplan-Meier analysis. All participants who withdrew from study drug prematurely but didn't switch to commercial product were counted as "events". Kaplan-Meier estimate of the probability of discontinuation at the specified time or earlier. Number of Participants continuing on RTG at each time of withdrawal were analyzed (represented as n=X in category title).
Change From Baseline in Blood Pressure
Time frame: Baseline and Up to Month 108
Systolic blood pressure (SBP) and diastolic blood pressure (DBP) was obtained in supine (Su) position and again in standing (St) position after the participant was standing for approximately 2 minutes at each study visit (Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). Not Applicable (NA) indicates that data were not available.
Change From Baseline in Heart Rate
Time frame: Baseline and Up to Month 108
Heart rate (HR) was measured in supine (Su) position and again in standing (St) position after the participant was standing for approximately 2 minutes at each study visit (Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Change From Baseline in Body Temperature
Time frame: Baseline and Up to Month 108
Body temperature was measured in degree Celsius at each study visit (Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available
Change From Baseline in Weight
Time frame: Baseline and Up to Month 108
Weight was measured in ordinary indoor clothing (without shoes) and was recorded at each study visit (On Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
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)
Time frame: Baseline and Up to Month 108
A 12-lead ECG was performed at each study visit during the first year of the study (Month 1, Month 3, Month 6, Month 9, Month 12) and annually after one year. The following electrocardiogram parameters are presented PR Interval, QRS Duration, Uncorrected QT interval (uQT), Corrected QT (Bazett's correction) interval (QTcB), Corrected QT (Friedericia's correction) interval (QTcF). Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Change From Baseline in the 12-lead Electrocardiogram (ECG) Parameter-RR Interval
Time frame: Baseline and Up to Month 108
A 12-lead ECG was performed at each study visit during the first year of the study (Month 1, Month 3, Month 6, Month 9, Month 12) and annually after one year. The following electrocardiogram parameters are presented: RR Interval. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles).
Change From Baseline in Electrocardiogram (ECG) Parameter-QRS Axis
Time frame: Baseline and Up to Month 108
A 12-lead ECG was performed at each study visit during the first year of the study (Month 1, Month 3, Month 6, Month 9, Month 12) and annually after one year. ECG parameter QRS Axis is presented here. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles).
Change From Baseline in Hematology Parameters- Bands, Basophils, Eosinophils, Lymphocytes, Metamyelocyte, Monocytes, Neutrophils, Platelets, White Blood Cells Count (WBC)
Time frame: Baseline and Up to Month 108
Following hematology parameters were assessed, Bands (Band neutrophils), Basophils, Eosinophils, Lymphocytes, Metamyelocyte, Monocytes, Neutrophils, Platelets and WBC. Hematology parameters were assessed at Month 1, Month 2, Month 3, Month 6, Month 8, Month 9, Month 10, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Change From Baseline in Hematology Parameter-Red Blood Cell Count
Time frame: Baseline and Up to Month 108
Red Blood Cell count (RBC) was assessed at Month 1, Month 2, Month 3, Month 6, Month 8, Month 9, Month 10, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available..
Change From Baseline in Haematocrit
Time frame: Baseline and Up to Month 108
Haematocrit was assessed at Month 1, Month 2, Month 3, Month 6, Month 8, Month 9, Month 10, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles).
Change From Baseline in Haemoglobin
Time frame: Baseline and Up to Month 108
Haemoglobin was assessed at Month 1, Month 2, Month 3, , Month 6, Month 8, Month 9, Month 10, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available..
Change From Baseline in Chemistry Parameters-Alkaline Phosphatase (AP), Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST)
Time frame: Baseline and Up to Month 108
Alkaline phosphatase (AP), Alanine aminotransferase (ALT), Aspartate aminotransferase (AST) were assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Change From Baseline in Chemistry Parameters-Bicarbonate, Blood Urea Nitrogen (BUN), Calcium, Chloride, Cholesterol, Non-fasting Glucose, Phosphorus, Potassium, Sodium, Urea
Time frame: Baseline and Up to Month 108
Bicarbonate (Bic.), BUN, Calcium (Ca), Chloride (Cl), Cholesterol (Cho.), Non-fasting glucose (NFG), Phosphorus (P), Potassium (Ka), Sodium (Na), Urea were assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Change From Baseline in Chemistry Parameters -Creatinine, Total Bilirubin (TB), Uric Acid (UA)
Time frame: Baseline and Up to Month 108
Creatinine, Total bilirubin (TB), Uric acid (UA) were assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Change From Baseline in Chemistry Parameter-Total Protein
Time frame: Baseline and Up to Month 108
Total Protein (TP) was assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles)
Change From Baseline in Urine Specific Gravity
Time frame: Baseline and Up to Month 108
Urine Specific gravity (USG) was assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Change From Baseline in Urine Power of Hydrogen (pH)
Time frame: Baseline and Up to Month 108
Urine pH was assessed at Month 1, Month 3, , Month 6, Month 9, Month 12 and every 4 months after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). NA indicates that data were not available.
Change From Baseline in Post-void Residual Bladder Ultrasound Volume
Time frame: Baseline and Up to Month 108
Post-void residual (PVR) bladder was assessed using ultrasound scan to assess urinary retention at Month 1, Month 3, Month 12 and annually after Month 12. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles)
Change From Baseline in Overall American Urological Association (AUA) Symptom Index Score
Time frame: Baseline and Up to Month 108
An AUA Symptom Index is a 7-item Likert-scored scale describing urinary bladder function and was completed by the Investigator to assess the participant's urinary voiding function at Month 1, Month 3, Month 12 and annually after Month 12. The index scale ranges from 0-35, where higher scores are indicative of a worse issue. Scores are categorized as 0-7 mild, 8-19 moderate and >19 severe. Baseline assessment in this study is defined as the last assessment for the endpoint in parent study taken prior to the first active treatment with Retigabine. Change from Baseline was calculated as post-Baseline value minus Baseline value. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles)
Number of Participants With Abnormal Results in Physical Examination
Time frame: Up to Month 108
A complete physical examination was performed at the end of each 12 month study cycle. Only those participants available at the specified time points were analyzed (represented by n=X in the category titles). If a participant had an abnormal result for at least one body system of exam, that participant was included in the 'Abnormal' category
Number of Participants With Abnormal Results of Neurological Examination
Time frame: Up to Month 108
Participants were assessed at Month 1, Month 3, Month 6, Month 9, Month 12 and every 4 months after Month 12. Participants in the worst category among the results of all neurological examination parameters are presented. Abnormal results were categorised as Abnormal not Clinically Significant (AbNCS)and Abnormal and Clinically Significant (AbCS). Only those participants available at the specified time points were analyzed (represented by n=X in the category titles)
Number of Participants With Pigmentation of Non-retinal Ocular Tissue
Time frame: Assessed up to a maximum of 9 years
The ophthalmologist/retina specialist determined the presence or absence of abnormal discoloration of all non-retinal ocular tissues. Only those participants available at the specified time points were analyzed.
Number of Participants With Pigmentation of Retinal Ocular Tissue
Time frame: Assessed up to a maximum of 9 years
The ophthalmologist/retina specialist determined the presence or absence of abnormal discoloration of retinal ocular tissues. It included Pigmentary abnormalities in the macula, of peripheral retina as well as in both of them.. Only those participants available at the specified time points were analyzed.
Number of Participants With Abnormal Pigmentation of Skin, Including the Skin Around the Eyes and the Eyelids, Lips, Nails, or Mucosa
Time frame: Assessed up to a maximum of 9 years
An assessment of the participant's nails, lips, skin and mucosa was completed by the investigator at the 4 monthly study visits. The assessment of the participant's skin included assessment of the skin around the eyes and the eyelids,lips, nails, and mucosa
Number of Participants With a Clinically Significant Decrease in Visual Acuity From Initial Examination
Time frame: Assessed up to a maximum of 9 years
A comprehensive eye examination was conducted by retina specialist or general ophthalmologist to assess best corrected visual acuity. An initial comprehensive eye examination was completed by an ophthalmologist for all participants. This exam was not associated with a specific visit. Thereafter, eye examinations was performed approximately every 6 months. Eye examination was introduced following protocol amendment and was conducted in all participants. Participants discontinued before implementation of this amendment and who have not had a comprehensive eye examination and skin examination (and follow-up by a dermatologist, if clinically indicated) were asked to return to the clinic for an evaluation of their skin (and follow-up dermatology examination, if clinically indicated) and for a comprehensive eye examination. Number of Par. with both initial and at least one follow-up exam while on RTG treatment were analyzed.
Number of Participants With a Decrease in Confrontational Visual Field From Initial Examination
Time frame: Assessed up to a maximum of 9 years
Decrease in confrontation visual field is defined as a participant having a normal initial exam and an abnormal exam thereafter or, a response of clinically significant worsening in either eye since the last assessment.
Number of Participants With Resolution of Abnormal Eye Pigmentation After Discontinuation of Retigabine
Time frame: 2 years and 9 months
The ophthalmologist/retina specialist determined the presence or absence of retinal and non-retinal ocular abnormalities. Retinal abnormalities included abnormalities in the macula and/or the peripheral retina and non-retinal ocular pigmentary abnormality.
Number of Participants With Resolution of Dermatologist Confirmed Abnormal Discoloration After Discontinuation of Retigabine
Time frame: 2 years 9 months
An assessment of the participant's nails, lips, skin and mucosa was completed by the investigator at the 6 monthly SFUCP study visits. The assessment of the participant's skin included assessment of the skin around the eyes and the eyelids, lips, nails, and mucosa.
Time From Discontinuation of Retigabine to Resolution of Abnormal Eye Pigmentation
Time frame: 2 years 9 months
Retinal pigmentary abnormality was determined by either an ophthalmologist or retina specialist. Retinal pigmentary abnormality included pigmentary abnormality of macula, pigmentary abnormality of the peripheral retina and non-retinal ocular pigmentary abnormality. If a participant had pigmentary abnormality of macula and pigmentary abnormality of the peripheral retina both should be resolved in order for retinal pigmentary abnormality to be considered resolved. If a participant had non-retinal ocular pigmentary abnormality in more than location (conjunctiva, sclera, cornea, iris or lens), all should be resolved for non-retinal pigmentary abnormality to be considered resolved. Only participants with resolution of the specified pigmentation are included in this analysis.
Time From Discontinuation of Retigabine to Resolution of All Dermatologist-Confirmed Abnormal Discoloration
Time frame: 2 years 9 months
Assessments were at approximately 6-monthly intervals (timed relative to the participants previous dermatology assessment) until the abnormal discoloration either resolved or stabilized (as defined by no changes over 2 consecutive 6-monthly assessments performed by the dermatologist over at least 12 months after discontinuation of retigabine). The assessment of the participant's skin included assessment of the skin around the eyes and the eyelids, lips, nails, and mucosa. Only participants with resolution of the specified tissue are included in this analysis.
6 secondary outcomes
Percentage Change From Baseline in the 28-day Partial Seizure
Time frame: Assessed up to a maximum of 9 years
Number of Responders
Time frame: Assessed up to a maximum of 9 years
Number of Participants Who Were Seizure Free for Any 6 Continuous Months
Time frame: Assessed up to a maximum of 9 years
Number of Participants Who Were Seizure Free for Any 12 Continuous Months
Time frame: Assessed up to a maximum of 9 years
Percentage of Seizure-free Days
Time frame: Assessed up to a maximum of 9 years
Change From Baseline in Quality of Life in Epilepsy (QOLIE)-31-P Questionnaire
Time frame: Assessed up to a maximum of 9 years
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 31 Jul 2020.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: Yes. IPD for this study will be made available via the Clinical Study Data Request site.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
GSK Clinical Trials study director
GlaxoSmithKline
51 sites in 5 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Ezogabine: USAN Retigabine (International Nonproprietary Name) in people with Epilepsy, run by GlaxoSmithKline at 51 sites in 5 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 31 Jul 2020. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 51 sites in United States, Mexico, Argentina, Brazil, Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 25 Nov 2016). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of Participants With Treatment-emergent Serious Adverse Event (SAE) and Adverse Event (AE) (time frame: Assessed up to a maximum of 9 years). The study lists 33 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 31 Jul 2020.