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# Eisai/Purdue NDA Filed for Insomnia
- URL: https://www.fdaweb.com/eisai-purdue-nda-filed-for-insomnia/
- Published: 2019-01-16T12:00:00.000Z
- Updated: 2026-09-15T00:54:54.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5143162

Eisai and Purdue Pharma have submitted an NDA for lemborexant for treating insomnia. The submission was based on data from two pivotal Phase 3 clinical studies in patients with insomnia — SUNRISE 1 (Study 304) and SUNRISE 2 (Study 303) — that enrolled about 2,000 patients. SUNRISE 1 included the first Phase 3 head-to-head comparison versus zolpidem ER (sanofi-aventis’ Ambien) and objectively assessed sleep parameters (time to sleep onset, sleep efficiency, and wake after sleep onset), the companies say. SUNRISE 2 was a 12-month study and subjectively assessed for ability to fall asleep and stay asleep based on patient self reports (sleep diaries).

Lemborexant works by acting on the orexin neurotransmitter system and is believed to regulate sleep and wake by dampening wakefulness without impeding the ability to awaken to external stimuli, Eisai and Purdue say. A Phase 2 clinical study of lemborexant in patients with irregular sleep-wake rhythm disorder and mild to moderate Alzheimer’s dementia is also underway.