Abstracts

RATIONALE: Levetiracetam (LEV) is a new antiepileptic drug available for treatment of epilepsy. The efficacy of levetiracetam (LEV) was assessed in a medically intractable adult epilepsy population. Specifically, we determined the percent of responders, the magnitude of their improvement and their optimal dose and blood level range. We also determined the number of patients who showed no response to the drug, and the number who stopped the drug because of side effects. The reader should be able to evaluate the efficacy of LEV and understand a target dose range and blood level range likely to be useful in treatment with LEV.
METHODS: We retrospectively reviewed 42 outpatient charts of adult patients with medically intractable epilepsy who began treatment with LEV between November 2000 and October 2001. Excluded from analysis were patients who had nonepileptic seizures, or had surgery for epilepsy while on LEV, or whose seizure counts were not reliable. Seizure type and frequency were tabulated using reports of the patient, family, or caregiver as documented in the medical record. Seizure counts were determined for the 6 months prior to LEV use and compared with a minimum of 6 months after initiation. Demographics, seizure types and frequency, number of previous AEDs, number of concomitant AEDs, adverse events, dose at time of best response, and corresponding blood levels were recorded when available. Patients were identified who stopped LEV because of side effects, and the nature of their side effects was recorded.
RESULTS: 42 patients met inclusion criteria including 23 males and 19 females (ages 18-67, mean 40 years). 5 (12%) discontinued LEV because of side effects: 3 because of behavior change; 1 due to gait disturbance; 1 due to depression. 11 (26%) had no significant improvement and discontinued LEV. 9 (21%) had no improvement but remained on LEV. 17 (40%) responded to treatment: 8 became seizure free; 6 had [gt]75% reduction in seizures; 2 had [gt]50% reduction; 1 had 25% reduction. Mean dose at the time of maximum efficacy in the 17 responders was 1750 mg/day (range 1000-3000 mg, median 1750mg). Mean concurrent LEV blood levels (available for 12 responders) was 22 mg/ml (range 13-42 mg/ml, median 19 mg/ml). 0-5 (mean 1.8) concomitant AED[scquote]s were used. Seizure types will be discussed.
CONCLUSIONS: 38% of the 42 medically intractable adults responded to LEV with [gt]50% reduction in seizure frequency, with 8 becoming seizure free. 12% stopped LEV due to side effects. LEV appears to be a very useful drug in this intractable population.