Abstracts

To evaluate the efficacy of oxcarbazepine monotherapy in patients with partial seizures switching from either carbamazepine or another antiepileptic drug (AED) due to lack of seizure control or poor tolerability.
Patients aged [ge]12 years experiencing 2[ndash]40 partial seizures per month while receiving treatment with an AED in the 2 months prior to study entry were included in this prospective, open-label, multicenter study. Following a 2-week Screening Phase, patients entered a 16-week Treatment Phase in which oxcarbazepine was initiated at daily doses of 8[ndash]10 mg/kg (patients [le]60 kg) or 600 mg (patients [ge]60 kg). Oxcarbazepine was titrated up over 4 weeks while their existing AED monotherapy was concurrently tapered off. The most common AED at study entry was carbamazepine (44%). This analysis was carried out to compare the efficacy of oxcarbazepine monotherapy in patients switching from carbamazepine or another AED due to lack of seizure control (56%) or poor tolerability (43%).
A total of 245 patients were enrolled in this study. Of the 176 patients for whom data were available, 87 were switched to oxcarbazepine from carbamazepine and 89 from another AED. For patients who experienced at least one seizure at baseline (defined as 3 months prior to Week 1), the median reduction in seizure frequency at endpoint relative to baseline was significant for both the patients who were switched from carbamazepine (54%; p=0.0021) or from another AED (73%; p[lt]0.001). Overall, for those patients who were switched from carbamazepine monotherapy, 55% (47/87) and 40% (35/87) had a 50% and 75% reduction in seizure frequency, respectively, and 30% (26/87) were seizure-free at endpoint. For those patients who were switched from another AED, 56% (50/89) and 49% (44/89) had a 50% and 75% reduction, respectively, and 42% (37/89) were seizure-free at endpoint. For those patients who were switched to oxcarbazepine from carbamazepine due to lack of efficacy yielded the following 50%, 75% and 100% response rates: 53% (32/60), 35% (21/60), and 22% (13/60), respectively. Similarly for those patients who were switched to oxcarbazepine from another AED due to lack of efficacy, the following 50%, 75% and 100% response rates were obtained: 51% (30/59), 41% (24/59), and 31% (18/59), respectively. Similar response rates for those patients who were switched due to poor tolerability with carbamazepine therapy were noted for both groups.
Oxcarbazepine monotherapy was efficacious in patients with partial seizures whether switching from previous treatment with carbamazepine or another AED due to lack of seizure control or poor tolerability.
[Supported by: Novartis]