Long-term effect of everolimus on epilepsy and growth in children under 3 years of age treated for subependymal giant cell astrocytoma associated with tuberous sclerosis complex.

Background: Tuberous sclerosis complex (TSC) is a genetic disorder characterized by increased mammalian target of rapamycin (mTOR) activation and growth of benign tumors in several organs throughout the body. In young children with TSC, drug-resistant epilepsy and subependymal giant cell astrocytomas (SEGAs) present the most common causes of mortality and morbidity. There are also some reports on the antiepileptic and antiepileptogenic potential of mTOR inhibitors in TSC. However, the data on everolimus efficacy and safety in young children are very limited.

Aims: To show the long-term safety data and the effect of everolimus treatment on epilepsy in children under the age of 3 who received everolimus for SEGAs associated with TSC.

Methods: We present the results of everolimus treatment in 8 children under the age of 3 who participated in EXIST-1 study. Five patients presented with active, drug-resistant epilepsy at baseline. The mean follow-up is 35 months (33-38 months) and all children are still on treatment.

Results: In 6 out of 8 children, at least a 50% reduction in SEGA volume was observed. In 1 child with drug-resistant epilepsy, everolimus treatment resulted in cessation of seizures and in 2 other children, at least a 50% reduction in the number of seizures was noted. The incidence of adverse events (AE) was similar to that observed in older children and adults.

Conclusions: This study suggests that everolimus is effective and safe in infants and young children with epilepsy and SEGA associated with TSC and offers a valuable treatment option.