Brivaracetam is superior to levetiracetam in a rat model of post-hypoxic myoclonus.

In the present study, we evaluated the anti-seizure and anti-myoclonic activity of levetiracetam and brivaracetam in an established rat model of cardiac arrest-induced post-hypoxic myoclonus. We found that brivaracetam (0.3 mg/kg, the minimal effective dose) was more potent than levetiracetam (3 mg/kg, the minimal effective dose) against post-hypoxic seizures. The anti-seizure activity of both compounds occurred 30 min following intraperitoneal (i.p.) administration and was maintained over the entire 150 min post-dose observation period. Both brivaracetam and levetiracetam significantly reduced auditory stimulated post-hypoxic myoclonus from a dose 0.3 mg/kg. At that dose, the anti-myoclonic activity of brivaracetam was already maximal whereas it continued to increase in a dose-relation manner with levetiracetam, suggesting that brivaracetam is a more potent agent. The onset and the duration of anti-myoclonic activity of both compounds were similar. These findings demonstrate that brivaracetam possesses more potent anti-seizure and anti-myoclonic activity than levetiracetam in an established rat model of cardiac arrest-induced post-hypoxic myoclonus.