Trial of Cannabidiol (CBD; GWP42003-P) for Infantile Spasms (GWPCARE7)

Key Inclusion Criteria: * Participant is aged 6- 24 months (inclusive) in the first cohort or aged 1-24 months (inclusive) in the second cohort, at the time of consent. * Participant is diagnosed with IS and has failed to respond adequately following treatment with 1 or more approved IS therapies. * To be considered hypsarrhythmia, as defined for use in the study, the electroencephalography (EEG) background must be slowed and have multifocal spikes. In addition, it must be either high voltage (above 300 µV) or have electrodecrement/discontinuity. Key Exclusion Criteria: * Participant is currently taking or has taken clobazam or any mammalian target of rapamycin (mTOR) inhibitor within the 2 weeks prior to the screening visit. * Participant has a QT interval, corrected for heart rate with Bazett's formula (QTcB), of 460 msec or greater on ECG. * Participant's caregiver is currently giving or has given recreational or medicinal cannabis, or synthetic cannabinoid-based medications, within the 1 month prior to the screening visit. * Participant's caregiver is unwilling to abstain from giving the participant (including the participant's mother abstaining themselves, if breastfeeding)recreational or medicinal cannabis, or synthetic cannabinoid-based medications (other than the study drug) during the trial. * Participant has any known or suspected hypersensitivity to cannabinoids or any of the excipients of the study drug, such as sesame oil. * Participant has significantly impai…