The drug discovery research conducted on lemborexant (brand name: Dayvigo), the dual orexin receptor antagonist discovered by Eisai Co Ltd, has been honored with The Pharmaceutical Society of Japan (PSJ) Award for Drug Research and Development 2024.

The PSJ Award for Drug Research and Development is one of a series of awards presented by the PSJ and is dedicated to researchers who have conducted outstanding research work that has contributed to medicine through the innovative development of a pharmaceutical drug or applicable technology related to the pharmaceutical sciences. The PSJ evaluates award contenders based on the ingenuity of the research itself, as well as the effectiveness and safety of the related pharmaceutical product(s) or the innovativeness of the related medical treatment or treatment technology. 

Eisai is a four-time winner of the award for drug discovery research: 

  • in 1998 on donepezil hydrochloride, an Alzheimer’s disease treatment;
  • in 2013 on eribulin mesylate, an anti-cancer agent;
  • in 2020 on lenvatinib, a multikinase inhibitor; and 
  • in 2021 on perampanel, an AMPA-type glutamate receptor antagonist. 

Why Lemborexant

PSJ shared the following rationale for selecting lemborexant: “Unlike conventional drugs, based on the fact that the main cause of insomnia is the nocturnal hyperactivation of the wakefulness pathway, the compound targets inhibition of the wakefulness system, which is considered a rational therapeutic approach. The compound is highly original in its unique structure based on trisubstituted cyclopropanes and has overcome many challenges in its optimization to a compound with a balanced profile by overcoming many pharmacokinetic and safety issues. 

“In preclinical and clinical studies, it has demonstrated a superior efficacy and safety profile that sets it apart from conventional drugs, and the compound is meeting the unmet medical needs of many insomnia patients both in Japan and overseas.” 

Lemborexant is currently approved for the indication of insomnia in over 15 countries, including the United States, Japan, Canada, Australia, and countries in Asia. 

Theme of Awarded Research

Drug discovery research of lemborexant, novel dual orexin 1/2 receptor antagonist for the treatment of sleep disorders 

Award recipients: 

  • Taro Terauchi (Protein Integrity & Homeostasis Domain Head, DHBL, Eisai) 
  • Takashi Ueno (Senior Scientist, Global DMPK, BA Unit, Global PPD Function, DHBL, Eisai)
  • Shoji Asakura (Executive Director, Global Drug Safety, BA Unit, Global PPD Function, DHBL, Eisai)
  • Naoki Kubota (Director, Japan and Asia Clinical Development, CEG, DHBL, Eisai) 
  • Carsten Beuckmann (Former employee of Eisai)

Eisai considers neurology, including insomnia, a therapeutic area of focus. 

Illustration 118314995 © Pawel Talajkowski |