A Randomized Controlled Trial of Cannabidiol (GWP42003-P, CBD) for Seizures in Tuberous Sclerosis Complex (GWPCARE6)


  • Study type

  • Study phase

  • Study IDs

  • Describes the nature of a clinical study. Types include:

    • Observational study — observes people and measures outcomes without affecting results.
    • Interventional study (clinical trial) — studies new tests, treatments, drugs, surgical procedures or devices.
    • Medical records research — uses historical information collected from medical records of large groups of people to study how diseases progress and which treatments and surgeries work best.
  • During the early phases (phases 1 and 2), researchers assess safety, side effects, optimal dosages and risks/benefits. In the later phase (phase 3), researchers study whether the treatment works better than the current standard therapy. They also compare the safety of the new treatment with that of current treatments. Phase 3 trials include large numbers of people to make sure that the result is valid. There are also less common very early (phase 0) and later (phase 4) phases. Phase 0 trials are small trials that help researchers decide if a new agent should be tested in a phase 1 trial. Phase 4 trials look at long-term safety and effectiveness, after a new treatment has been approved and is on the market.

  • Site IRB
    • Rochester, Minnesota: 16-006618
    NCT ID: NCT02544763
    Sponsor Protocol Number: GWEP1521

About this study

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 receive 1 of 2 doses of GWP42003-P or matching placebo. The primary clinical hypothesis is that there will be a difference between GWP42003-P and placebo in their effect on seizure frequency.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. If you need assistance understanding the eligibility criteria, please contact the study team.

See eligibility criteria

Inclusion Criteria:

  • Participant has a well-documented history of epilepsy, with compatible electroencephalogram (EEG) and clinical history.
  • Participant has a clinical diagnosis of Tuberous Sclerosis Complex (TSC) according to the criteria agreed by the 2012 International TSC Consensus Conference.
  • All medications or interventions for epilepsy (including ketogenic diet and any neurostimulation devices for epilepsy) must have been stable for 1 month prior to screening and the participant is willing to maintain a stable regimen throughout the trial.

Exclusion Criteria:

  • Participant has a history of pseudo-seizures.
  • Participant has clinically significant unstable medical conditions other than epilepsy.
  • Participant has an illness in the 4 weeks prior to screening or randomization, other than epilepsy, which in the opinion of the investigator could affect seizure frequency.
  • Participant has undergone general anesthetic in the 4 weeks prior to screening or randomization.
  • Participant has undergone surgery for epilepsy in the 6 months prior to screening.
  • Participant is being considered for epilepsy surgery or any procedure involving general anesthesia.
  • Participant is taking felbamate, and they have been taking it for less than 1 year prior to screening.
  • Participant is taking an oral mTOR inhibitor.
  • Participant has any known or suspected hypersensitivity to cannabinoids or any of the excipients of the Investigational Medicinal Product (IMP), such as sesame oil.
  • Participant had active suicidal plan/intent in the past 6 months, or has a history of suicide attempt in the last 2 years, or more than 1 lifetime suicide attempt.
  • Participant has C-SSRS grade 4 or 5 at screening.
  • Participant is currently using or has in the past used recreational or medicinal cannabis, or cannabinoid-based medications, within the 3 months prior to screening and is unwilling to abstain for the duration for the study.
  • Participant has tumor growth which, in the opinion of the Investigator, could affect the primary endpoint.
  • Participant has significantly impaired hepatic function at the screening or randomization visit
  • Participant has received an IMP within the 12 weeks prior to the screening visit.

Participating Mayo Clinic locations

Study statuses change often. Please contact us for help.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Elaine Wirrell, M.D.

Closed for enrollment

Contact information:

Spoorthi Jagadish


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