Patient Information
The patient was diagnosed with epilepsy and Epilepsia partialis continua (EPC) at two years of age, following initial presentation with an arrhythmic, twitching right foot, and constant jerking. Due to a family history of epilepsy, including her father and grandmother, she was referred to a neurologist for further assessment. Electroencephalography (EEG) revealed EPC, characterized by recurrent focal seizures occurring every few seconds or minutes. Genetic testing ruled out mitochondrial disorders, Rasmussen’s encephalitis, and SCN1A abnormalities, but revealed an SCN2A mutation. EPC symptoms persisted before the onset of more noticeable seizures, which were triggered by various factors, including a hot bath. These seizures included focal episodes, with the patient’s head deviating to the left. Muscle twitching in her right foot spread up her leg and across to the left side, escalating into tonic or tonic-clonic seizures with asymmetric tonic limb posturing (Figure 4 sign). These episodes lasted 30–60 seconds and increased in frequency from twice weekly to twice daily. The patient also developed ataxia with seizure progression, impairing coordination, balance, manual dexterity, and motor skills. Lennox-Gastaut Syndrome was ultimately diagnosed.

The patient received seven anti-seizure treatments, namely levetiracetam, perampanel, topiramate, clobazam, carbamazepine, lamotrigine, and lacosamide. The patient experienced adverse effects from these treatments, including loss of appetite and impaired vocal and speech ability due to topiramate, which improved with dose reduction. Additionally, she developed lamotrigine-related dysphagia and was unable to tolerate lamotrigine preparations, experienced behavioral issues associated with clobazam, and ataxia and dizziness were exacerbated by perampanel. Several treatments, particularly clobazam, had sedative effects and increased seizure clustering, contributing to a cyclical pattern in which the patient experienced seizure clusters for a few hours, followed by sleep, only to awaken and undergo further seizures. Some anti-seizure drugs worsened seizure activity, necessitating their withdrawal. Alternative treatments were explored; however, hemispherectomy and vagus nerve stimulation were contraindicated due to the nature of the patient's pathological brain activity. Dietary therapy with the ketogenic diet was also deemed unsuitable due to pre-existing diabetes mellitus. The high frequency and severity of seizures significantly disrupted the patient’s education, leading to prolonged school absences and a markedly reduced quality of life. Furthermore, considerable stress was placed on the patient's caregiver due to the demands of full-time care, frequent hospital visits, and managing prolonged seizures, resulting in emotional distress.

Medical Cannabis Therapeutic Intervention
With the deterioration of the patient’s condition, including multiple and repetitive seizures, medication side effects, worsening ataxia rendering her unable to sit or walk unaided, and the complete inability to attend school, it was decided to start treatment with medicinal cannabis. From the age of six, treatment with a phytocannabinoid combination of CBD and THC at a respective ratio of 20:1 (CannEpil®), produced in compliance with EU-GMP requirements by Argent BioPharma, was initiated via a private prescription. Within four weeks of beginning CBP treatment, there was notable clinical improvement in the patient's condition. The patient was able to maintain balance, sit independently, and walk, in addition to regaining some speech and cognitive abilities. The patient continued background anti-seizure drugs (topiramate and clobazam); however, higher doses continued to cause significant side effects. Following CannEpil treatment, the patient was subsequently able to reduce the doses of topiramate and clobazam, resulting in a cessation of clusters of seizures.

Outcomes
The patient has seen significant improvements in her quality of life, including being able to return to school full-time. She has developed a full vocabulary and regained the ability to communicate effectively, facilitating social integration and improved peer interactions.  Although she retains a developmental delay, she is able to maintain her academic curriculum. Seizures still occur one to two times per day but are brief, allowing the patient to recover rapidly, typically within 10 to 15 seconds. The patient can participate in many aspects of everyday life, including singing songs and watching YouTube videos. Her appetite has increased, and her fine motor skills have improved, enabling her to hold a pencil, draw, color, and sharpen pencils. She retains a degree of ataxia but is now able to stand, sit independently, and engage in physical activities.