A phase III study has shown that the AMPA receptor antagonist perampanel, when added to standard antiepileptic drugs, improves seizure control in patients with drug-resistant partial-onset seizures. 388 patients were randomly assigned to receive placebo, 8 mg perampanel or 12 mg perampanel for 19 weeks. Seizure frequency was significantly reduced in patients receiving adjunctive perampanel versus placebo. Tolerability of the drug was reasonable, with adverse events such as dizziness leading to treatment discontinuation in 40 patients.