Lemborexant pills obtained manufacturing and marketing approval in Japan for the treatment of insomnia in 2.5mg, 5mg, and 10mg strengths, Eisai Co announced.
Lemborexant is a dual orexin receptor antagonist that inhibits orexin neurotransmission regulating sleep-wake rhythm by binding competitively to the two subtypes of orexin receptors (OX1R and OX2R).
Blocking the binding of wake-promoting neuropeptides orexin to its receptors is thought to suppress the wake drive by balancing sleep-wake circuitry.
Lemborexant acts as a competitive antagonist with stronger inhibition effect on OX2R. Higher affinity and faster on/off receptor kinetics of lemborexant to OX2R, which also suppresses non-REM sleep, indicate its potential to facilitate the non-sedative onset and maintenance of sleep.
This approval was mainly based on the results of two pivotal Phase 3 clinical studies in adult patients with insomnia, SUNRISE 21 and SUNRISE 12, enrolling approximately 2,000 patients. Approval was also based on important safety studies (Study1083, Study1064), which included assessment of residual next-morning effects via postural stability (falling prediction indicator), memory after middle-of-the-night awakening.
In December 2019, the USFDA approved lemborexant for the treatment of adult patients with insomnia, characterized by difficulties with sleep onset and/or sleep maintenance.