International forskning

Efficacy of cannabidiol in convulsive and nonconvulsive seizure types associated with treatment-resistant epilepsies in the Expanded Access Program

Robert J Flamini 1, Anne M Comi 2, E Martina Bebin 3, Michael G Chez 4, Gary Clark 5, Orrin Devinsky 6, Shaun A Hussain 7, Paul D Lyons 8, Anup D Patel 9, Jillian L Rosengard 10, Farhad Sahebkar 11, Eric Segal 12, Laurie Seltzer 13, Jerzy P Szaflarski 14, Arie Weinstock 15

  • 1PANDA Neurology, Atlanta, Georgia, USA.
  • 2Kennedy Krieger Institute, Johns Hopkins School of Medicine, Baltimore, Maryland, USA.
  • 3University of Alabama School of Medicine, Birmingham, Alabama, USA.
  • 4Sutter Health, Roseville, California, USA.
  • 5Texas Children’s Hospital and Baylor College of Medicine, Houston, Texas, USA.
  • 6NYU Langone Comprehensive Epilepsy Center, New York, New York, USA.
  • 7David Geffen School of Medicine and UCLA Mattel Children’s Hospital, Los Angeles, California, USA.
  • 8Virginia Comprehensive Epilepsy Program, Winchester, Virginia, USA.
  • 9Nationwide Children’s Hospital, Columbus, Ohio, USA.
  • 10Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, New York, USA.
  • 11Jazz Pharmaceuticals, Carlsbad, California, USA.
  • 12Northeast Region Epilepsy Group, Hackensack University Medical Center, Hackensack, New Jersey, USA.
  • 13University of Rochester Medical Center, Rochester, Minnesota, USA.
  • 14University of Alabama at Birmingham, Birmingham, Alabama, USA.
  • 15University at Buffalo and Oishei Children’s Hospital, Buffalo, New York, USA.


The cannabidiol (CBD) Expanded Access Program (EAP), initiated in 2014, provided CBD (Epidiolex) to patients with treatment-resistant epilepsy (TRE). In the final pooled analysis of 892 patients treated through January 2019 (median exposure = 694 days), CBD treatment was associated with a 46%-66% reduction in median monthly total (convulsive plus nonconvulsive) seizure frequency. CBD was well tolerated, and adverse events were consistent with previous findings. We used pooled EAP data to investigate the effectiveness of add-on CBD therapy for individual convulsive seizure types (clonic, tonic, tonic-clonic, atonic, focal to bilateral tonic-clonic), nonconvulsive seizure types (focal with and without impaired consciousness, absence [typical and atypical], myoclonic, myoclonic absence), and epileptic spasms. CBD treatment was associated with a reduction in the frequency of convulsive seizure types (median percentage reduction = 47%-100%), and nonconvulsive seizure types and epileptic spasms (median percentage reduction = 50%-100%) across visit intervals through 144 weeks of treatment. Approximately 50% of patients had ≥50% reduction in convulsive and nonconvulsive seizure types and epileptic spasms at nearly all intervals. These results show a favorable effect of long-term CBD use in patients with TRE, who may experience various convulsive and nonconvulsive seizure types. Future controlled trials are needed to confirm these findings.

Keywords: absence seizures; antiseizure medications; clonic seizures; epileptic spasms; seizure frequency.