Abstracts

To evaluate the long-term efficacy and tolerability of oxcarbazepine monotherapy in an open-label follow-up to a multicenter, randomized, double-blind, controlled study (Guerreiro et al. 997;27:205-213).
Data from the 56-week Double-blind Phase (DB) was combined with the 56-week Open-label Follow-up (OF) to compare the long-term efficacy and tolerability of oxcarbazepine and phenytoin. Of the 193 newly diagnosed adolescents and children (aged 5-17 years) with partial epilepsy treated during the DB, 129 patients entered OF, including 2 patients who changed therapy from phenytoin to oxcarbazepine. This study considered just the 191 patients who did not change therapy (97 oxcarbazepine, 94 phenytoin), with 127 patients (69 oxcarbazepine and 58 phenytoin) patients continuing into OF.
No difference was seen in the weekly seizure rates during the 112-week follow-up (median = 0 throughout the period for both groups). The seizure-free rates at 112 weeks were not significantly different: 52.6% [plusmn]5.7% and 42.4% [plusmn]6.9% for oxcarbazepine and phenytoin, respectively. However, the hazard for discontinuation due to adverse events (AEs) over 112 weeks was significantly higher for phenytoin compared with oxcarbazepine (HR = 10.6, phenytoin versus oxcarbazepine, 95% CI: 1.4 to 82.9). The adverse-event profile in the OF was similar to that reported for the DB¹. One oxcarbazepine patient discontinued due to AEs during the DB and none during OF, while 9 phenytoin patients discontinued during the DB and 1 during OF. There were 5 (4 DB, 1 OF) oxcarbazepine and 3 (3 DB, 0 OF) phenytoin patients discontinuing due to lack of therapeutic control, with no significant difference in these rates.
Children are significantly more likely to continue oxcarbazepine because of superior tolerability compared with phenytoin over long-term treatment. Oxcarbazepine is at least as effective as phenytoin for long-term management of children with partial seizures.
[Supported by: Novartis Pharma AG]