Everolimus as adjunctive treatment in tuberous sclerosis complex-associated epilepsy in children

INTRODUCTION: Tuberous sclerosis complex (TSC) is a rare autosomal dominant multi-organ disease. In TSC, epilepsy is frequent and often treatment refractory. Dysfunction of the tumour-suppressing hamartin/tuberin complex leads to an over-activated mammalian target of rapamycin (mTOR) signalling pathway and uncontrolled cell growth. Protocolled treatment of TSC-associated epilepsy with the mTOR inhibitor everolimus has recently been approved by The Danish Medicines Council in Denmark. METHODS: Clinical data on the first Danish paediatric patients treated with everolimus for epilepsy and a review of the literature are presented. RESULTS: Four patients met the inclusion criteria and had been treated for more than 12 months. Onset of epilepsy was at a median age of 1.1 years (range: 0.3-3.3 years) and current age was 3.4 years (range: 2.2-7.4 years). The previous median number of antiepileptic drugs was 5.0 (range: 2-10) and the concomitant median number of antiepileptic drugs was 2.5 (range: 1-4). Several other treatment modalities had been or were still being applied, including ketogenic diet (n = 3), vagus nerve stimulation (n = 1) and epilepsy surgery (n = 2). The number of focal seizures was in the 20-160 range per week before everolimus. All patients had a > 50% seizure reduction after 12 months of everolimus treatment. One patient became seizure free. Side effects were mild and self-limiting. CONCLUSIONS: Early data on everolimus as an adjunctive treatment in TSC-associated epilepsy are promising with regards to both effect and tolerability.