Progabide (SL 76002) was studied in a randomized double-blind crossover trial using 20 outpatients suffering from partial complex seizures. Progabide was added to the concomitant antiepileptic treatment in a fixed dosage schedule. The design included an open therapy control unit. No significant difference was established between the number of partial seizures during treatment with progabide and placebo. A trend was observed for lower seizure frequency of secondary generalized seizures during treatment with progabide. Only mild and transient side effects were observed. There was no difference between the side effects of progabide and placebo.