Glioma-associated epilepsy is associated with excessive glutamate signaling. We hypothesized that perampanel, an amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptor antagonist, would treat glioma-related epilepsy. We conducted a single-arm study of adjunctive perampanel for patients with focal-onset glioma-associated seizures. The most common related adverse events were fatigue and dizziness. Three out of 8 participants had self-reported seizure reduction and an additional 3 reported improved control. Of these 6, 5 had isocitrate dehydrogenase 1 mutant gliomas. We conclude that perampanel is safe for patients with glioma-related focal-onset epilepsy. Further study into the association between AMPA signaling, IDH1 status and seizures is warranted.