Abstracts

RATIONALE: To compare lamotrigine (LAMICTAL?, LTG) monotherapy vs monotherapy with older conventional (CONV) AEDs (i.e., carbamazepine, phenytoin, or divalproex sodium) in patients who have failed a previous course of treatment with one of these older AEDs. METHODS: The study consisted of 3 Phases: Screen, Escalation/Taper, and Treatment. Patients were randomized to either the LTG or CONV group and then treated in an open-label fashion. The LTG group (n=57) were converted from their current AED to LTG monotherapy via a protocol-specified dosing algorithm. The CONV group (n=58) were converted from their current AED to another CONV AED (physician's choice) via standard dosing guidelines. The primary measure of treatment success was completion of the Treatment Phase. Other measures included seizure frequency, time to discontinuation, investigator- and patient-rated global assessments, adverse events (AEs), and vital signs. RESULTS: More LTG patients completed the study than CONV patients (65% vs 57%). Twenty six percent of CONV patients prematurely discontinued for AEs compared to 16% of LTG patients. The groups were comparable in seizure reduction: ?75% reduction LTG=26%, CONV=28%; ?50% reduction LTG=35%, CONV=33%. The investigator global assessment demonstrated more LTG patients than CONV were judged to have marked improvements in seizure frequency (37% vs 20%), seizure intensity (37% vs 19%), intellectual functioning (29% vs 9%), AEs (33% vs 15%), overall status (31% vs 13%) and better improvement in global self-assessment (73% vs 58%). CONCLUSIONS: Data suggest that when monotherapy with a CONV AED fails or is poorly tolerated, switching to LTG monotherapy may have advantages over monotherapy with an alternative older AED.