Early treatment and development in TSC: Insights from the PREVeNT Trial
About this study
This research is part of the PREVeNT clinical trial, which aimed to determine whether starting treatment before seizures begin could prevent or reduce later developmental challenges and autism in children with TSC (Tuberous Sclerosis Complex). This study looked at whether starting vigabatrin (an anti-epileptic medication) early could help prevent intellectual and developmental disability and autism spectrum disorder (ASD) in infants with TSC. The study included 84 infants with TSC aged 6 months or younger, who had no history of seizures yet and no seizure activity on EEG at the time of recruitment.
How the study was conducted
The study involved 84 infants with TSC. They were placed into two main treatment groups: early vigabatrin (started prior to the onset of seizures) or standard treatment (vigabatrin only started after first seizure). The remainder of the participants were infants who never developed seizures during the study.
The study followed the infants from 6 months to 3 years of age, and assessed features such as cognitive skills, language and motor development, and autism-related behaviours. Importantly, COVID-19 restrictions affected some assessments, with some needing to be done by telehealth and fewer families able to complete follow-up.
Outcomes of the study
Disappointingly, the study found that starting vigabatrin early did not improve development or autism-related outcomes. Children in the early treatment and standard treatment groups had similar outcomes across developmental domains (including cognitive, language, motor or adaptive).
Developmental scores for children who did develop seizures were generally in the low‑average to below‑average range, which is common in TSC. Developmental scores showed some decline over time, particularly in children who developed seizures.
Children who never developed seizures during the study period had higher developmental scores than both treatment groups.
About 31% of children in the study were diagnosed with ASD by age 3, which is consistent with previous TSC research. None of the children in the group that never developed seizures were diagnosed with ASD.
The findings suggest that epilepsy itself, rather than when vigabatrin is started, is a major driver of developmental and autism‑related outcomes in TSC.
Implications of the study
This study suggests that the early treatment with vigabatrin does not change neurodevelopmental outcomes, although it may delay the onset of seizures.
Close EEG monitoring still remains important, and reducing the severity of epilepsy may still be a key factor to improving developmental outcomes. Further studies with longer-term follow-up are needed to understand outcomes beyond the age of 3 years.
DISCLAIMER
This information is intended to provide some insights into recent TSC-related research. It is not intended to, and it should not, constitute medical or other advice. Readers are warned not to take any action without first seeking medical advice.
O’Kelley SE, Capal JK, McPherson TO, Patrick KE, Pearson DA, Davis PE, Currans K, Byars AW, Porter BE, Sahin M, Taub KS, Rajaraman R, Randle S, McClintock WM, Koenig MK, Frost MD, Werner K, Nolan DA, Wong M, Krefting JL, Cutter GR, Krueger DA, Bebin EM; PREVeNT Study Group. Neurodevelopmental Outcomes From the PREVeNT Trial. Pediatr Neurol. 2025 Dec; 173:88–97.