The Safety of Keppra as Adjunctive Therapy in Epilepsy (SKATE) study aimed to evaluate the safety and efficacy of levetiracetam (Keppra, LEV) as add-on therapy for refractory partial seizures in clinical practice. This Phase IV, 16-week, open-label study recruited patients > or =16-year old with treatment-resistant partial seizures. LEV (1000 mg/day) was added to a stable concomitant antiepileptic drug regimen. LEV dosage was adjusted based on seizure control and tolerability to a maximum of 3000 mg/day. 1541 patients (intent-to-treat population) were recruited including 1346 (87.3%) who completed the study and 77.0% who declared further continuing on LEV after the trial. Overall, 50.5% of patients reported at least one adverse event that was considered related to LEV treatment. The most frequently reported drug-related adverse events were mild-to-moderate somnolence, fatigue, dizziness and headache. Serious adverse events considered related to LEV occurred in 1.0% of patients. 7.5% of patients reported adverse events as the most important reason for study drug discontinuation. The median reduction from baseline in the frequency of all seizures was 50.2%; 15.8% of patients were seizure free; 50.1% had seizure frequency reduction of > or =50%. At the end of the study, 60.4% of patients were considered by the investigator to show marked or moderate improvement. There was a significant improvement in health-related quality of life as assessed with the QOLIE-10-P (total score increasing from 55.6 to 61.6; p<0.001). This community-based study suggests that LEV is well tolerated and effective as add-on therapy for refractory partial seizures in adults. These data provide supportive evidence for the safety and efficacy of LEV demonstrated in the pivotal Phase III placebo-controlled studies.