Abstracts

Because elderly patients are generally more susceptible to drug side effects when compared with younger adults, adverse event (AE) data in adults [ge]65 yrs of age treated with topiramate (TPM) monotherapy studies were analyzed. AE data were from 5 double-blind trials: 4 dose-controlled trials in patients with newly diagnosed epilepsy (N=1208); 1 placebo-controlled trial in patients with essential tremor (N=221). In epilepsy studies, target dosages were 50-500 mg/day TPM monotherapy. 3 of 4 studies allowed dose flexibility; patients had to be maintained on assigned dose (100 or 200 mg/day) in 1 study. Target dose for essential tremor patients, 400 mg/day, with dose flexibility. In 50% of tremor patients, TPM added to 1 anti-tremor agent. Median double-blind treatment duration: epilepsy patients, 8 mos; tremor patients, 6 mos. Adverse event data available for 170 epilepsy patients and 121 tremor patients [ge]65 yrs of age. Epilepsy patient data pooled (TPM 50, N=69; TPM 100, N=15; TPM 200, N=62; TPM 400, N=10; TPM 500, N=14) and compared with TPM (N=57) and placebo-treated (N=65) tremor patients. Data also pooled for TPM-treated epilepsy and tremor patients and compared with AE data for younger TPM-treated adults (16-64 yrs, N=793) with epilepsy. 86% of epilepsy patients were treated with [le]200 mg/day TPM; median dose in tremor patients, 375 mg/day. Table shows most common AEs ([ge]10% incidence) and neurobehavioral AEs occurring more frequently for TPM vs. placebo. [table1] Higher incidence of paresthesia, weight decrease, appetite decrease, taste perversion, memory difficulty, nausea, concentration/attention difficulty and language problems in tremor vs. epilepsy patients may reflect higher TPM doses in tremor study. AEs occurring more often in epilepsy vs. tremor may reflect influence of epileptogenic substrate. Expectations that TPM would be more poorly tolerated in elderly patients than in younger adults, particularly in terms of neurobehavioral AEs, are not supported by these data. TPM monotherapy appears to be well-tolerated by the elderly. (Supported by Johnson [amp] Johnson Pharmaceutical Research [amp] Development; Ortho-McNeil Pharmaceutical)