Spanish expanded access program showed CBD reduced seizures by 48% in treatment-resistant epilepsy | Research

The takeaway

In a Spanish expanded access program of 102 patients with severe epilepsy, purified CBD reduced total monthly seizures by 47.6%, with 44.9% achieving at least 50% seizure reduction at 6 months.

Families of children with treatment-resistant epilepsy, neurologists, and health system planners considering CBD access programs.

47.6% median seizure reduction in patients who failed 7.5 prior medications

What the researchers found

44.9% of patients had at least 50% seizure reduction at 6 months, 38.9% at 12 months. Median total seizures per month reduced by 47.6% from baseline to last visit. Seizure severity decreased in 61.1% at 12 months. Quality of life improved 21.2%. Adverse events in 66.7%, most commonly somnolence (34.3%).

Why it matters

This real-world expanded access data complements clinical trial results by showing how CBD performs in a broader, highly refractory patient population in routine clinical practice.

The numbers in context

102 patients. Mean age 15.9. Mean 7.5 prior failed ASMs. Mean CBD dose 13.0 mg/kg/day. Seizure reduction at 6 months: 44.9% had 50%+ reduction. Median seizure reduction: 47.6%. Quality of life improved 21.2%. Somnolence 34.3%, diarrhea 12.7%. Discontinuation for AEs alone: 7.8%.

How the study worked

Multicenter retrospective observational study of 102 patients (mean age 15.9, 59% LGS, 12% Dravet, 29% other syndromes) treated with purified CBD at 14 Spanish hospitals. Highly refractory population with mean 7.5 previously failed anti-seizure medications.

What this study cannot tell us

Retrospective, uncontrolled design. No placebo comparison. Self/caregiver-reported seizure counts. Heterogeneous patient population. Selection bias from expanded access enrollment.

How to read the evidence

Moderate: multicenter real-world data from 102 patients, but retrospective and uncontrolled.

When this study was published

Published in 2022.

The bigger picture

Expanded access programs provide valuable data on medications before or alongside formal approval, reaching patients who cannot wait for or access clinical trials.

Questions still open

Would the other 29% of epilepsy syndromes (non-DS, non-LGS) respond as well in controlled trials? Is the 13 mg/kg/day dose optimal? Why does response rate decrease slightly from 6 to 12 months?

Common questions

How treatment-resistant were these patients?

Very. The average patient had tried and failed 7.5 different anti-seizure medications before receiving CBD, making any seizure reduction clinically meaningful.

Did quality of life improve?

Yes. Quality of life scores improved by 21.2% from baseline to last visit, based on the CAVE scale.

What were the main side effects?

Somnolence (34.3%) and diarrhea (12.7%) were most common. Adverse events occurred in 66.7% but only 7.8% discontinued solely due to side effects.

Read the original research

Outcomes from a Spanish Expanded Access Program on cannabidiol treatment in pediatric and adult patients with epilepsy.

Epilepsy & behavior : E&B, 137(Pt A), 108958

View on PubMed ↗Publisher’s paper ↗

Citation

Villanueva, Vicente; García-Ron, Adrián; Smeyers, Patricia; Arias, Eva; Soto, Victor; García-Peñas, Juan José; González-Alguacil, Elena; Sayas, Débora; Serrano-Castro, Pedro; Garces, Mercedes; Hampel, Kevin; Tomás, Miguel; Lara, Julian; de Toledo, María; Barceló, Ines; Aledo-Serrano, Angel; Gil-Nagel, Antonio; Iacampo, Lucas; Falip, Mercè; Saiz-Diaz, Rosa Ana; Gómez-Ibañez, Asier; Sopelana, David; Sanchez-Larsen, Alvaro; López-González, Francisco Javier. (2022). Outcomes from a Spanish Expanded Access Program on cannabidiol treatment in pediatric and adult patients with epilepsy.. Epilepsy & behavior : E&B, 137(Pt A), 108958. https://doi.org/10.1016/j.yebeh.2022.108958