“Objective: To evaluate the long-term safety and efficacy of add-on cannabidiol (CBD) in patients with seizures associated with tuberous sclerosis complex (TSC) in the open-label extension (OLE) of the randomized, placebo-controlled phase 3 trial GWPCARE6 (NCT02544763). Results of an interim (February 2019 data cut) analysis are reported.
Methods: Patients who completed the randomized trial enrolled to receive CBD (Epidiolex® in the United States; Epidyolex® in the EU; 100 mg/mL oral solution). The initial target dose was 25 mg/kg/day, which, based on response and tolerability, could be decreased or increased up to 50 mg/kg/day. The primary end point was safety. Key secondary end points included percentage reduction in TSC-associated (countable focal and generalized) seizures, responder rates, and Subject/Caregiver Global Impression of Change (S/CGIC).
Results: Of 201 patients who completed the randomized phase, 199 (99%) entered the OLE. Mean age was 13 years (range, 1-57). At the time of analysis, 5% of patients had completed treatment, 20% had withdrawn, and 75% were ongoing. One-year retention rate was 79%. Median treatment time was 267 days (range, 18-910) at a 27 mg/kg/day mean modal dose. Most patients (92%) had an adverse event (AE). Most common AEs were diarrhea (42%), seizure (22%), and decreased appetite (20%). AEs led to permanent discontinuation in 6% of patients. There was one death that was deemed treatment unrelated by the investigator. Elevated liver transaminases occurred in 17 patients (9%) patients; 12 were taking valproate. Median percentage reductions in seizure frequency (12-week windows across 48 weeks) were 54%-68%. Seizure responder rates (≥50%, ≥75%, 100% reduction) were 53%-61%, 29%-45%, and 6%-11% across 12-week windows for 48 weeks. Improvement on the S/CGIC scale was reported by 87% of patients/caregivers at 26 weeks.
Significance: In patients with TSC, long-term add-on CBD treatment was well tolerated and sustainably reduced seizures through 48 weeks, with most patients/caregivers reporting global improvement.”
https://pubmed.ncbi.nlm.nih.gov/34957550/
“The results of our study show that add-on CBD can be an efficacious long-term treatment for TSC-associated seizures with manageable side effects and has been approved in patients as young as 1 year of age in the United States.”
“Cannabinoids have been found to be effective in controlling seizures and the highly purified form of cannabinoid derived for Cannabis sativa . Cannabidiol (CBD) is now approved for Lennox-Gastaut syndrome (LGS) and Dravet syndrome. CBD was used in a 9-year-old boy with LGS (unknown etiology) with very good results. The electroencephalography (EEG) response was very dramatic with near normalization of EEG background and complete control of seizures. The effect of CBD on EEG with such an improvement has not been described previously. Also, this adds to evidence that early intervention in LGS with CBD might be more helpful and improve outcomes.”
“Voltage-gated sodium channels are targets for a range of pharmaceutical drugs developed for treatment of neurological diseases.
“Pharmaceutically purified oral cannabidiol (CBD) has been recently approved by the US Food and Drug Administration and European Medicines Agency as treatment of seizures associated with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS), which are severe and difficult-to-treat developmental and epileptic encephalopathies with onset in early childhood.
“In recent years there has been a growing appreciation by regulatory authorities that cannabis-based medicines can play a useful role in disease therapy.
“Highly purified cannabidiol (CBD) has demonstrated efficacy with an acceptable safety profile in patients with Lennox-Gastaut syndrome or Dravet syndrome in randomized, double-blind, add-on, controlled phase 3 trials.
“Mutations in SYNGAP1 are associated with developmental delay, epilepsy, and autism spectrum disorder (ASD). Epilepsy is often drug-resistant in this syndrome with frequent drop attacks.