AUStralian study of titration to effect profile of safety (AUS-STEPS): high-dose gabapentin (neurontin) in partial seizures.

PURPOSE: To evaluate the safety, tolerability, efficacy, and impact on quality of life of gabapentin (Neurontin; GBP) as adjunctive therapy in patients with refractory partial seizures.

METHODS

AUS-STEPS was an open-label, multicenter, prospective study in patients experiencing partial seizures who were inadequately controlled with one to three concurrent antiepileptic drugs (AEDs). GBP treatment was titrated to a maximum of 4,800 mg/day, over a treatment period of 24 weeks, to achieve an efficacious and tolerable dosage. Efficacy was assessed by seizure-frequency data. Quality of life was evaluated by using the QOLIE-10 questionnaire, and safety was assessed by adverse-event reports and clinical laboratory findings.

RESULTS

A total of 176 patients received treatment with GBP, with 174 evaluable for intention-to-treat (ITT) efficacy analysis. A reduction of >50% in overall seizure frequency was observed in 93 patients (53%). There was a small (4.6%) overall improvement in QOLIE-10 score. The most frequent adverse events were dizziness (31%), fatigue (29%), somnolence (27%), headache (21%), and ataxia (20%), with no major increase seen in adverse events necessitating discontinuation as the dose of GBP was titrated upward.

CONCLUSIONS

This study indicates that patients with partial epilepsy may be effectively treated with GBP at dosages of < or =4,800 mg/day, without altering the safety profile of the drug.