LONG-TERM SAFETY AND EFFICACY OF GABAPENTIN (NEURONTIN) AS ADD-ON THERAPY IN PATIENTS WITH REFRACTORY PARTIAL SEIZURES

In an international, multicenter, open-label study, the long-term effi cacy and safety of gabapentin (GBP, Neurontin) as add-on therapy were investigated in 203 patients with partial seizures refractory to stand ard antiepileptic drugs (AEDs). All patients enrolled in this study ha d experienced improved seizure control with GBP in one of four previou s, short-term studies. Patients received mean GBP dosages of 1,283 to 2,220 mg/day for periods of less than or equal to 1,894 days (mean, 38 5 days). For purposes of efficacy analyses, data were divided into 12- week treatment periods. During long-term treatment, the efficacy of GB P was shown to be maintained by several primary efficacy measures. In all of the 12-week treatment periods, the percentage of change in seiz ure frequency from baseline was equal to or less than -24%, responder rate was >35%, and response ratio ranged between -0.2 and -0.338. Resu lts for secondary efficacy measures also indicated that efficacy was m aintained. The favorable safety profile of GBP also was maintained dur ing long-term treatment. Our results suggest that GBP is an effective, safe, and well-tolerated add-on treatment for long-term use in patien ts with partial seizures refractory to standard AEDs.