– Eisai to continue to develop and commercialize lemborexant globally –

May 1, 2019 I Eisai Co., Ltd. (Headquarters: Tokyo, CEO: Haruo Naito, “Eisai”) announces today that its U.S. subsidiary Eisai Inc. has bought out Purdue Pharma L.P.’s rights in the worldwide collaboration for the development and commercialization of lemborexant, an investigational sleep-wake regulation agent being studied for the treatment of multiple sleep-wake disorders, including insomnia and irregular sleep-wake rhythm disorder (ISWRD) in patients with Alzheimer’s Disease. Eisai group will solely conduct the development and the commercialization of lemborexant globally.

Discovered by Eisai, lemborexant is an investigational dual orexin receptor antagonist. The U.S. Food and Drug Administration (FDA) accepted the New Drug Application (NDA) for lemborexant for use in the treatment of insomnia disorders for review in March 2019 and set a Prescription Drug User Fee Act (PDUFA) date for December 27, 2019. For Japan, a marketing authorization application for lemborexant for use in the treatment of insomnia disorder has been submitted to the Pharmaceuticals and Medical Devices Agency (PMDA) in March 2019 and is currently under review. Furthermore, a Phase II clinical study of lemborexant for ISWRD in patients with Alzheimer’s Disease is ongoing.

Through lemborexant, Eisai is striving to address unmet medical needs and contribute to further increasing the benefits for patients with sleep disorders and their families.

[Notes to editors]

1. About Lemborexant

Lemborexant is a novel investigational small molecule compound, discovered and developed by Eisai in-house scientists, that inhibits orexin signaling by binding competitively to both orexin receptor subtypes (orexin receptor 1 and 2). In individuals with normal daily sleep-wake rhythms, orexin signaling is believed to promote periods of wakefulness. In individuals with sleep-wake disorders, it is possible that orexin signaling that regulates wakefulness is not functioning normally, suggesting that inhibiting inappropriate orexin signaling may enable initiation and maintenance of sleep. Additionally, a Phase 2 clinical study of lemborexant in patients with irregular sleep-wake rhythm disorder (ISWRD) and mild to moderate Alzheimer’s dementia is underway.

SOURCE: Eisai