NCT01721317

Dose-Optimization, Adjunctive Treatment Study of Ezogabine/Retigabine Immediate Release in Partial-onset Seizures

Study PTG116878, a Dose-Optimization Study of Ezogabine/Retigabine Immediate Release Tablets Versus Placebo in the Adjunctive Treatment of Subjects With Partial-Onset Seizures

• Status: Terminated
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 6 (actual)
• Sponsor: GlaxoSmithKline · Industry
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

This is a Phase IV adjunctive treatment dose-optimization study evaluating the efficacy, safety, and health outcomes of ezogabine/retigabine immediate release (IR) (GW582892) compared with placebo in adult subjects with partial-onset seizures (POS). This randomized, double-blind, placebo-controlled, parallel-group, multicenter study will compare ezogabine/retigabine IR (investigator-selected daily doses of 600 milligram (mg)/day, 750 mg/day, 900 mg/day, 1050 mg/day or 1200 mg/day) with placebo. Study drug will be taken three times a day (TID) in equally or unequally divided doses. The study design includes up to a 10-week (wk) Screening (≤2 wks)/Baseline (8 wks) Phase, a Titration Phase (2 wks), Dose-Optimization Phase (8 wks), Maintenance Phase (8 wks), and Taper/Follow-Up Phase (3 wks). The total duration of the study for each subject will be approximately 31 wks, and at minimum approximately 27 wks if subjects provide reliable 28-day retrospective seizure data. Approximately 280 subjects will be screened with approximately 208 subjects randomly assigned to 1 of 2 treatment groups in a 2:1 ratio (ezogabine/retigabine IR, or placebo). Subjects will be instructed to start investigational product (IP) the day after the baseline visit. During the first week of the Titration Phase, subjects will be taking 300 mg/day (100 mg TID). During the second week, subjects will be taking 450 mg/day (150 mg/day TID). At the beginning of the Dose-Optimization Phase (3rd week of study drug) subjects will take 600 mg/day (200 mg TID) for one week. Thereafter during the Dose-Optimization Phase, subjects will continue to increase their daily dose by 150 mg per week until they have achieved their optimal tolerated dose. During this phase, the investigator may choose to have the subject stay on his/her designated dose for another week before attempting a dose increase until reaching a dose of 1200 mg/day. In addition, in the context of tolerability issues, the subject may be reduced to the preceding dose level for one week before attempting to increase the dose again at the next scheduled time point until the subject reaches optimal dose. Subjects unable to tolerate a minimum of 600 mg/day will be discontinued from the study. The Maintenance Phase will begin at Week 10 (Visit 8) and will last 8 weeks. During the Maintenance Phase, subjects will remain on the daily TID dose achieved at the end of the Dose-Optimization Phase. Seizure type and frequency will be monitored throughout the study via a Seizure Calendar and will be evaluated at each study visit. Subjects will be instructed to complete the daily Seizure Calendar during each phase of the study.

Conditions

• Seizures

Interventions

Type	Name	Description
DRUG	Ezogabine/Retigabine IR	Subjects received drug (dose strength 300 mg to 1200 mg) orally with or without food. The 3 daily doses are to be administered with approximately an 8-hour interval between them.
DRUG	Placebo	Matching placebo will be available

Timeline

• Start date: 2012-12-19
• Primary completion: 2013-06-20
• Completion: 2013-06-20
• First posted: 2012-11-05
• Last updated: 2020-12-30
• Results posted: 2014-03-26

Locations

11 sites across 2 countries: United States, Greece