Cannabidiol in Children With Refractory Epileptic Encephalopathy

Inclusion Criteria: * Age 1-10 years * Epileptic Encephalopathy * A minimum of at least 1 major seizure per week or 4 major seizures per month. For the purposes of this research study, a major seizure would include atonic, tonic, clonic, tonic-clonic, major myoclonic, myoclonic astatic seizures and epileptic spasms (including infantile spasms) * Refractory to anticonvulsant medication as per the International League Against Epilepsy (ILAE) Definition of failing 2 appropriate anticonvulsants at therapeutic doses * The ability to attend appointments regularly * Negative pregnancy test at screening for females who have reached menarche Exclusion Criteria: * Recent (\<1 month) change in anticonvulsant therapies including anticonvulsant medications, ketogenic diet or settings on Vagal Nerve Stimulator * Recent (\<6 months) change in intravenous immunoglobulin (IVIG) treatment * Initiation of ketogenic diet within 6 months (Patients must be on the ketogenic diet for at least 6 months to prevent any delayed response from the ketogenic diet affecting study results) * Implantation and activation of Vagal Nerve Stimulator within 12 months (Patients may have a vagal nerve stimulator for at least one year once again to prevent delayed response from the vagal nerve stimulator affecting study results) * Use of cannabis-based therapy within 2 months (Participants who have previously used a cannabis based therapy may be included if they have a 2 month period without use of cannabis based therapy prior to enrolment in the study) * Use of selective serotonin reuptake inhibitor (SSRI), tricyclic antidepressant or atypical neuroleptic medication in last month * Concomitant regular use of narcotics (Use of narcotics in emergency situations and supervised by a physician is allowed) * Initiation or dosage change of oral or injected steroids within 3 months * Allergy or known intolerance to any of the compounds within the study preparation * Inability of study participants to attend assessments on a monthly basis * Clinically significant cardiac, renal or hepatic disease (as assessed by the site investigator)