OUTCOME MEASURES FOR THE ASSESSMENT OF NEW ANTIEPILEPTIC DRUGS

For the approval of any new medicinal product quality, safety and effi cacy are essential requirements. This manuscript focusses on the clini cal development programme. For the investigation of antiepileptic drug s some international guidelines are of special importance. They are ba sed on the knowledge of many experts and can be seen as a consensus on minimal requirements; deviations must be thoroughly justified. In pha ses II and III, usually randomised, double-blind add-on studies versus placebo in patients with therapy-resistant seizures are used to get a n impression of the efficacy and certain safety issues. A clear dose-r esponse relationship may be a good indication for efficacy. However, a ssessment of safety of the new product in add-on studies is difficult. Therefore comparative phase III monotherapy studies versus establishe d antiepileptic drugs are essential to confirm the results obtained in add-on studies and are needed for a proper judgement of the efficacy/ safety balance. The percentage of reduction of seizure frequency has p layed a dominating role as efficacy criterium. Nowadays preference, is being given to the percentage responders. Which parameter is the most relevant for the given group of patients and what change is considere d clinically relevant must be thoroughly argued. The definition of res ponder should focus on major benefit for the patients involved.