Abstracts

Rationale: Epidiolex became the first FDA approved product containing cannabidiol to treat epilepsy in US at the end of last year. It is indicated for the treatment of drug resistant epilepsy in patients with Lennox-Gastaut Syndrome (LGS) or Dravet Syndrome (DS). Patients with LGS and DS often have intractable seizures which fail to come under control with traditional anticonvulsant medications. Having another treatment option for this refractory population may offer improved seizure control, decreased medication burden, and reduce side effects. The Comprehensive Epilepsy Center at Children’s Hospital Los Angeles serves a large, diverse population of children in Los Angeles Country and surrounding areas. The Center is staffed by four board certified Epileptologists. We review here our patient experience since Epidiolex received FDA approval. Methods: A retrospective chart review was completed of all patients who received a prescription for Epidiolex since the drug became FDA approved. Seizure frequency at baseline was determined from chart review. Maximal dose was documented. Seizure frequency at last follow-up was determined. Side effects, lab monitoring results including liver function tests and concomitant medication levels were reviewed. Patients who had not been on treatment for at least 3 months or who did not have follow-up data were excluded from analysis. Results: At our institution, one hundred fifty patients were prescribed Epidiolex since FDA approval. Twelve patients stopped medication prior to analysis due to lack of efficacy, side effects, or personal preference. Twenty-seven patients had insufficient follow-up time. Sixteen patients were missing follow-up information. Available for analysis were 95 patients, 87 with LGS or ‘other refractory epilepsy’, and 8 patients with DS. Most patients were started at 5mg/kg/day and escalated to 10mg/kg/day. Eleven patients had a final dose of 20mg/kg/day and ten patients had a final dose of 15mg/kg/day. Within the LGS group, 37% had no change in seizure frequency, 63% had a 50% or greater reduction in seizure frequency, and 11.5% were seizure free. Two of the seizure free patients had a VNS implanted around the time the Epidiolex was started. In the DS group, 25% had no improvement in seizure frequency and 75% had a 50% or greater reduction in seizures frequency, with 25% seizure free. For all patients, 69% of the non-responders continued on Epidiolex, and of these, 7 patients were able to stop at least one medication (most tapered off clobazam). Many families reported improved alertness and better school functioning. One patient with DS had not had an episode of status epilepticus since starting Epidiolex. Side effects were mild. The most common side effect was sedation for patients also on clobazam. Desmethylclobazam levels in these patients elevated often 2-4 times above baseline. Lowering the clobazam dose resolved this issue in most patients. Two patients had increased liver functions tests, both were on valproate. One was tapered completely off the valproate, while the other had the dose decreased. In both cases the enzymes normalized and the patients continued on Epidiolex. Conclusions: Epidiolex is a safe and effective treatment for Lennox-Gastaut Syndrome and Dravet Syndrome. Minimal side effects were reported, and most related to the interaction with clobazam. Overall, 64% of our patients had a 50% reduction in seizures, and 69% of our patients who did not have an appreciable change in seizure frequency decided to remain on therapy due to other benefits. Funding: No funding