Gamma-vinyl-GABA (vigabatrin) in the therapy of Lennox-Gastaut syndrome: an open study
The antiepileptic effect of vigabatrin (gamma-vinyl GABA, VGB) in children has been demonstrated in controlled and open studies. According to the literature, results were good to excellent in partial seizures (with and without becoming secondarily generalized) and promising in infantile spasms (IS). In patients with myoclonic epilepsies of early childhood and especially those with Lennox-Gastaut syndrome (LGS), the effect of VGB has been investigated only to a limited extent and the pattern of response was variable. The present open, add-on, dose-ranging study was initiated to assess the long-term effect and safety of VGB in a cohort of 20 children with LGS who were not responding sufficiently to first-line drug monotherapy with valproate (VPA) instead of adding classical second-line antiepileptic drugs [AEDs: benzodiazepines (BZD), phenobarbital (PB), primidone (PRM)], which usually are associated with rapid diminution of their antiepileptic properties and a high frequency of side effects. Eighty-five percent of children experienced a 50-100% reduction in seizure frequency, even after dose reduction of VPA. No serious side effects occurred except in 1 patient who experienced dyskinesia. Mood changes, sedation, ataxia, and hypersalivation, well-known complications of other AEDs, were not observed.