Abstracts

RATIONALE: The choices available for patients whose partial-onset seizures are not controlled with standard AEDs include seven new AEDs and vagal nerve stimulation (VNS). Efficacy and adverse event data from clinical trials provide a method of comparison among drugs. METHODS: Data from double-blinded, placebo controlled clinical trials of new AEDs and VNS were tabulated for responder rate (>50% decrease in partial-onset seizures). Success Rate was the responder rate for the AED minus the responder rate for placebo. Adverse events >5% were tabulated as complaint rates (proportion of patients receiving AED who reported the problem minus reports from the placebo group). The Summary Complaint Score is the total number of reports of individual events for each AED. RESULTS: Comparisons among AEDs using standardized definitions and terminology revealed distinct differences in the balance between efficacy and tolerability. Selection of an adjunct treatment should be based on the overall impact of the drug on the patient. Success Rates fell into two general groups: 12-20% for GBP, LTG, TGB, ZNS; and 27-29% for LEV, OCBZ, TPM (VNS 27%) Summary Complaint Scores also fell into two general groups with ranges of 27-71 for GBP, LEV, TGB, ZNS and 113-201 for LTG, OCBZ, TPM (VNS 198) (VNS trials did not include a placebo group.) CONCLUSIONS: Some drugs tested at very high doses showed good efficacy but at the cost of excessive adverse effects. Some drugs tested at low doses showed relatively low efficacy but few adverse effects. LEV was the only AED to demonstrate both a high Success Rate and a low Summary Complaint Score at typical doses.