Eisai Co. Ltd. and Purdue Pharma LP are seeking U.S. Food and Drug Administration approval for lemborexant as a treatment for insomnia, a sleep disorder.

The new drug application submitted to the regulator was based on the results of two phase 3 trials called Sunrise 1 and Sunrise 2, which enrolled about 2,000 patients.

Lemborexant works by acting the orexin neurotransmitter system, which regulates a person's wakefulness.

Tokyo's Eisai and Stamford, Conn.-based privately held company Purdue Pharma are jointly developing the therapy for sleep-wake disorders. Lemborexant is also slated for a phase 2 study in patients with irregular sleep-wake rhythm disorder and mild to moderate Alzheimer's dementia.