Cannabidiol Effective for Reducing Seizures in Treatment-Resistant Epilepsy

After 3 months of CBD therapy, median overall seizure frequency reduction was 45.1% in all patients and 62.7% in those with Dravet syndrome. Patients with Lennox-Gastaut syndrome had a median reduction of atonic seizures from baseline of 71.7%. Overall, 47% of all patients had at least a 50% reduction in seizures. At 3 months, seizure freedom occurred in 9% of patients and 13% of those with Dravet syndrome. Patients taking Clobazam had a higher rate of treatment response (57%) compared to those not on Clobazam co-therapy (39%).

Safety data from 313 patients from 16 sites was available. Twelve percent (36) of patients withdrew due to lack of efficacy. Adverse events occurred in more than 10% of patients, including somnolence (23%), diarrhea (23%), fatigue (17%), decreased appetite (17%), convulsions (17%), and vomiting (10%). Adverse events in 4% of patients led to discontinuation of CBD therapy. Serious adverse events were reported in 34% (106) of patients, including 7 deaths that were not considered to be treatment-related. Sixteen patients (5%) had serious adverse events considered to be treatment-related, including altered liver enzymes (4 patients [pts]; all were also on valproate and clobazam), status epilepticus/convulsion (4 pts), diarrhea (4  pts), decreased weight (3 pts), thrombocytopenia (1 pt), and others.

“These data reinforce and support the safety and efficacy we have shared in previous studies,” Dr. Devinsky said in a statement. However, he cautioned that these results are from an uncontrolled study, and further study is needed to confirm the drug’s ability to safely and effectively reduce seizures.

Randomized controlled trials are currently underway to further test the effectiveness of Epidiolex.