(747): Open label trial of levetiracetam for chronic lumbar post laminectomy pain

Abstract

This was an open label trial of Levetiracetam (LTM), a new generation anticonvulsant, in subjects with chronic lumbar post laminectomy pain (pain radiating below the knee) of at least 6 months duration. Prior to initiating drug, the following baseline measurements were obtained: 1) Daily Spontaneous Pain Score; 2) Beck Depression Inventory (BDI); 3) Sickness Impact Profile (SIP). Subjects with an average daily spontaneous pain score of >4/10 during the screening period entered a 2 week titration period and started on LTM at 500mg/day and titrated up to 3000 mg/day until they reached a target dose (defined as >30% reduction in pain or< 30% reduction in pain at the maximum dose). Subjects who reached a target dose were enrolled into a 4 week maintenance period. At the completion of the maintenance period, the baseline measurements were repeated. Eighteen subjects enrolled in the study with 14 completing the titration. Four subjects dropped out of the titration period due to side effects. The average daily dose of LTM at the end of titration was 2303 mg. Three subjects elected not to continue into the maintenance period due to lack of efficacy. Four out of the 18 subjects were considered responders (> 30% reduction in pain) with a mean of 55% reduction in pain. The mean baseline BDI score for responders and non responders was 2.25 and 17.5 respectively. The SIP score for responders and non responders was 16.25 and 48.85 respectively. 3 out of 4 responders had SIP scores below 10. Overall, LTM resulted in a small non significant decrease in pain score (baseline mean 59.3, end of maintenance mean 49.1). This study suggests that LTM is effective in lumbar post laminectomy pain patients with low baseline BDI and SIP scores. Further investigation of LTM in neuropathic pain is warranted.