Abstracts

Rationale: To evaluate the safety and feasibility of seizure prophylaxis with levetiracetam monotherapy in post-operative supratentorial glioma patients taking phenytoin preoperatively for tumor-related seizures. Methods: 30 patients were enrolled over a 13-month period. Patients met inclusion criteria if they had seizure history attributable to supratentorial glioma, were taking phenytoin monotherapy for seizure prophylaxis, were to undergo a craniotomy as standard management, had at most one previous resection, were over 18 years of age, and were free of other comorbidities. After signing an approved IRB consent form, patients were randomized in a 2:1 ratio to initiate levetiracetam therapy within 24 hours of surgery or to continue phenytoin therapy. Patients were followed for 6 months post-operatively with 2 telephone surveys and mail-in questionnaires conducted at 3 month intervals. The study’s anticipated conclusion is October, 2007. Results: Of the 30 patients enrolled, 20 were randomized to levetiracetam and 10 to phenytoin. There was 1 fatality within the levetiracetam group from complications of the primary pathology. As of May 1, 2007, 25 of 30 patients had completed the follow-up period. In the levetiracetam group, 2 patients had seizures reported: 1 responded to increased dosage; 1 followed self-discontinuation of therapy and, with resumption of therapy, seizures did not recur. No seizures were reported in the phenytoin group. Reported side effects were as follows (% levetiracetam group/% phenytoin group): dizziness (0/29), excessive sleepiness (17/57), difficulty with coordination (0/43), depression (28/43), insomnia (44/43), mood instability (5/0). No side effects required discontinuation of assigned therapy in either group. Conclusions: The pilot data presented here suggest that levetiracetam is a safe agent for seizure monotherapy following craniotomy for supratentorial glioma. Its side effect profile may also be less morbid than that of phenytoin. A large-scale, double-blinded, randomized control trial of levetiracetam vs phenytoin should now be conducted to assess equivalence in seizure control and better determine differences in side effect profiles. (This study is funded by UCB Pharma.)