MHLW approves Fycompa (perampanel) in Japan as an alternative epilepsy therapy when oral administration is temporarily not possible

Fycompa is a first-in-class AED discovered at Eisai’s Tsukuba Research Laboratories. The agent is a highly selective, noncompetitive AMPA receptor antagonist that is postulated to reduce neuronal hyperexcitation associated with seizures by targeting glutamate activity at AMPA receptors on postsynaptic membranes. Two oral formulations of Fycompa are available in Japan: a tablet and a fine granule formulation. Due to concern about the risks of seizures associated with interruption of administration when the drug cannot be taken orally temporarily, such as during surgery, it is suggested that epilepsy patients should continue treatment via routes other than oral administration. Since Fycompa is the only AMPA receptor antagonist-based AED, Eisai developed this injection formulation to meet the needs of patients who are unable to use oral administration, and filed a supplementary new drug application as a new route of administration in August 2022, leading to this approval.