Epilepsy is a neurological disorder affecting more than 50 million people globally, including more than 260,000 Canadians. Cannabidiol (CBD) reduces seizure frequency and improves quality of life for adults and children with Drug Resistant Epilepsy (DRE). Several uncontrolled, small, open label studies reported that CBD-enriched Cannabis Herbal Extract (CHE) resulted in a reduction of seizure frequency, but we lack critical information on efficacy, comparative effectiveness and dosing of CBD and ∆9-tetrahydrocannabinol (THC) in children and adults with DRE. CAN-DRE is an early phase, triple-blind, placebo-controlled, randomized clinical trial to answer the questions of if cannabinoids work to reduce seizures in children and adults (24 months to 55 years) with DRE and if CBD works better in an isolate or in a CBD-enriched Cannabis Herbal Extract. The primary outcome of CAN-DRE is reported monthly seizure count from baseline to maintenance phase.