A Phase 2, Double-blind, Randomized, Placebo-controlled Pharmacokinetic Trial in 2 Parallel Groups to Investigate Possible Drug-drug Interactions Between Stiripentol or Valproate and GWP42003-P in Patients With Epilepsy
A Phase 2, Double-blind, Randomized, Placebo-controlled Pharmacokinetic Trial in 2 Parallel Groups to Investigate Possible Drug-drug Interactions Between Stiripentol or Valproate and GWP42003-P in Patients With Epilepsy
This trial consists of 2 parts: a double-blinded phase and an open-label extension phase. The blinded phase only will be described in this record. Participants will be randomized in a 4:1 ratio to receive GWP42003-P or matching placebo. The hypothesis is that levels of stiripentol (STP) or valproate (VPA) may be altered (increased or decreased) as a result of using GWP42003-P.
Note: Participants who enroll in Sweden must be aged 18-55 years.
Key Inclusion Criteria:
Participant must be taking STP (for the STP arm) or VPA (for the VPA arm) and no more than 2 other antiepileptic drugs (AEDs) during the blinded period of the trial.
AED doses, including STP or VPA, must be stable for 4 weeks prior to screening and regimen must remain stable throughout the duration of the blinded period of the trial.
Participant must have a documented magnetic resonance imaging/computerized tomography of the brain that ruled out a progressive neurologic condition.
Participant must have experienced at least 1 countable uncontrolled seizure of any type (i.e., tonic-clonic, tonic, clonic, atonic, partial onset or focal: focal seizures with retained consciousness and a motor component, focal seizures with impaired consciousness, focal seizures evolving to bilateral secondary generalization) within 2 months prior to randomization.
Intervention with vagus nerve stimulation and/or ketogenic diet must be stable for 4 weeks prior to baseline and the participant must be willing to maintain a stable regimen during the blinded period of the trial.
Participant must abstain from alcohol during the blinded period of the trial.
Key Exclusion Criteria:
Participant has clinically significant unstable medical conditions other than epilepsy.
Participant has a history of symptoms related to a drop in blood pressure due to postural changes (e.g., dizziness, light-headedness, blurred vision, palpitations, weakness, syncope).
Participant has a QT interval, corrected for heart rate with Bazett's formula (QTcB), greater than:
Participant has any history of suicidal behavior or any suicidal ideation of type 4 or 5 on the C-SSRS in the last month or at screening.
Participant has had clinically relevant symptoms or a clinically significant illness in the 4 weeks prior to screening or enrollment, other than epilepsy.
Participant is currently using felbamate and has been taking it for less than 12 months prior to screening.
Participant has consumed alcohol during the 7 days prior to enrollment and is unwilling to abstain during the blinded phase of the trail.
Participant is currently using or has in the past used recreational or medicinal cannabis, or synthetic cannabinoid-based medications (including Sativex®) within the 3 months prior to trial entry.
Participant has any known or suspected history of any drug abuse or addiction.
Participant is unwilling to abstain from recreational or medicinal cannabis, or synthetic cannabinoid based medications (including Sativex) for the duration for the study.
Participant has consumed grapefruit or grapefruit juice 7 days prior to enrollment and is unwilling to abstain from drinking grapefruit juice within 7 days of pharmacokinetic visits.
Participant has any known or suspected hypersensitivity to cannabinoids or any of the excipients of the Investigational Medicinal Product (IMP), e.g., sesame oil.
Participant has received an IMP within the 12 weeks prior to the screening visit.
Participant has significantly impaired hepatic function at the screening or randomization visit, defined as any of the following: