Tolerability and safety of topiramate in chinese patients with epilepsy - An open-label, long-term, prospective study

Objectives: This study focused on (i) evaluating the long-term tolerability and safety of topiramate in Chinese patients with epilepsy, and (ii) comparing the tolerability and safety of topiramate monotherapy versus polytherapy in the same population. Methods: This was a prospective, open-label, long-term (36 months) clinical trial. 320 patients (275 adults and 45 children) with epilepsy were recruited into the study; of these, 156 patients had generalised seizures, 151 patients had partial seizures and 13 patients had unclassifiable seizures. All patients received topiramate similar to 200 mg/day either as monotherapy or as adjunctive therapy. At each visit, a physical examination and routine laboratory analysis were performed, and the adverse event (AE) profile was obtained by face-to-face interview. Results: 268 patients received topiramate <= 100 mg/day and 52 patients received topiramate 100-200 mg/day. Topiramate-associated AEs occurred in 98 patients (30.6%). The most common AEs were weight loss in 18 patients (8.4%), paraesthesias in 17 (7.2%), poor memory in ten (3.8%), and dizziness in six (2.8%). Most AEs were mild to moderate and transitory; discontinuation of topiramate was observed in 13 patients (4.1%) as a result of AEs such as impaired memory (seven patients [54%]), paraesthesias (four patients [31%]), and weight loss and cutaneous reaction (each one patient [7.5% each]). The rate of AEs was significantly higher with use of topiramate as monotherapy than as adjunctive therapy (68 patients vs 30 patients [47.8% vs 16.4%], respectively). Conclusion: Topiramate is well tolerated in Chinese patients with epilepsy in clinical practice. Compared with its use as adjunctive therapy, topiramate monotherapy is associated with a significantly higher frequency of adverse events.