TOKYO, Japan I October 28, 2016 I Eisai Co., Ltd. (Headquarters: Tokyo, CEO: Haruo Naito, “Eisai”) announced today the initiation of a Phase II clinical study of its internally-discovered oral dual orexin receptor antagonist lemborexant (development code: E2006) in patients with Irregular Sleep-Wake Rhythm Disorder (ISWRD) and mild to moderate Alzheimer’s disease (AD) dementia. Lemborexant is being jointly developed by Eisai and Purdue Pharma L.P. (Headquarters: Connecticut, United States, President and CEO: Mark Timney).
ISWRD is a type of circadian rhythm sleep disorder where the pattern of sleep and wakefulness that repeats itself over a 24 hour period in healthy individuals is broken down, and sleeping and waking occur instead at various times during the day and night. This is often observed in patients with neurodegenerative diseases such as AD. At the pre-investigational new drug meeting held with the U.S. Food and Drug Administration, it was confirmed ISWRD is different from general insomnia. There is no known treatment approved for an irregular sleep-wake pattern in patients, meaning this is a condition with high unmet medical need.
Study 202 is a multicenter, randomized, double-blind, placebo-controlled, parallel-group study of the efficacy and safety of lemborexant in approximately 125 patients aged 65 to 90 with ISWRD and mild to moderate AD. The primary objective will be to evaluate the sleep efficiency and wake efficiency during the last seven nights of 4 weeks of treatment with lemborexant compared to placebo as measured using actigraphy. An actigraph is a non-invasive device worn on the wrist, and is used for assessing the circadian rhythm of sleep-wake patterns continuously over several weeks.
Regarding the development of lemborexant, a Phase III clinical study (Study 304) in patients with general insomnia is also in progress. Study 304 is a Phase III clinical study evaluating the efficacy and safety of lemborexant in approximately 950 participants, 55 years or older (at least 60% aged 65 years or older) with insomnia disorder. In addition to Study 304, three other Phase III studies are being planned.
Dr. Lynn Kramer, Chief Clinical Officer and Chief Medical Officer of Eisai’s Neurology Business Group, commented “We are aiming to develop lemborexant as a first-in-class medicine for ISWRD to improve sleep and wake patterns for patients with dementia, and as a best-in-class medicine for insomnia disorder. We are striving to deliver lemborexant and contribute to increasing the benefit to patients around the world as soon as possible.”
Eisai considers neurology a therapeutic area of focus and is committed to new drug development in this field. Through research and development on lemborexant, Eisai is striving to fulfill new unmet medical needs in ISWRD and dementia in addition to insomnia to further contribute to increasing the benefit for patients and their families.