[Clinical experiences with pregabalin in the treatment of focal epilepsies]

Pregabalin is an antiepileptic drug recently approved in the European Union for add-on therapy of focal epilepsy. A review of its clinical and pharmacological characteristics is, therefore, appropriate.

This drug, which binds to a subunit of voltage-dependent calcium channels in neuronal membranes, has a favourable pharmacokinetic profile. Pregabalin administered in two or three divided doses was compared to placebo in three double-blind randomised multicenter clinical trials, including 1,052 patients with focal epilepsy not controlled with other antiepileptic drugs. Results of these studies showed efficacy at doses of 150 mg per day, and a dose-response relationship up to doses of 600 mg per day. At the highest dose, mean seizure reduction for pregabalin was 44.3 to 54%, a significant reduction compared to placebo (p < or =0.0001), and a response rate of 43.5 to 51% (p < or =0.001). In one of these studies 12% of patients treated with pregabalin at 600 mg per day were seizure free for the last month of therapy while another study demonstrated its efficacy when used on a twice daily schedule. Subsequent open studies demonstrated a sustained efficacy of the drug. The most common adverse events were dizziness, somnolence, ataxia, asthenia, and weight gain. Withdrawal from controlled studies due to adverse effects was 15.3% in patients treated with pregabalin, compared with 6.15% in those receiving placebo.

Pregabalin favourable pharmacokinetic profile, in addition to its good tolerability and remarkable efficacy make this new antiepileptic drug an attractive option for the treatment of focal epilepsies.