The small molecule orexin receptor antagonist will be made available for the US market in 2 different doses, in 2020.
The US Food and Drug Administration (FDA) has approved lemborexant (Dayvigo) for the treatment of insomnia in adults.
The Esai Pharmaceuticals small molecule orexin receptor antagonist will be made available in 5 mg and 10 mg doses.
Lemborexant's approval was based on data from a pair of pivotal phase 3 studies, SUNRISE 1 and SUNRISE 2, that assessed lemborexant versus placebo for 1 and 6 months.
SUNRISE 1 was a one-month, placebo- and active-controlled, double-blind study that included the first phase 3 head-to-head comparison versus zolpidem tartrate extended release, an active comparator, that evaluated the safety and efficacy of lemborexant in 1006 participants 55 years of age and older with insomnia. Lemborexant 5 mg and 10 mg demonstrated a statistically significant superiority over placebo on the primary end point, which was mean change in log-transformed latency to persistant sleep (LPS) from baseline to end of treatment. Treatment with the study drug also demonstrated statistically significant improvements in sleep efficiency and wake after sleep onset compared with placebo.
In SUNRISE 2, patients age 18 or older with insomnia were randomly assigned to lemborexant 5 mg, 10 mg, or placebo. Compared to placebo, the study drug was found to be statistically significantly superior on the primary end point, which was mean change from baseline to end of treatment at 6 months for log-transformed, patient-reported sleep onset latency. The study drug was also statistically superior to placebo on the secondary end points, including change from baseline to end of treatment on patient-reported sleep efficiency and wake after sleep onset. After 6 months of treatment, patients in the placebo group were re-randomized to either 5 mg or 10 mg lemborexant, while patients in the original treatment group maintained their therapy.
Twelve-month results from SUNRISE 2 showed that sleep onset latency was lowered by almost 20 minutes for patients treated with both 5 mg and 10 mg of lemborexant, with maintained efficacy through months 6 and 12. In addition, subjective sleep efficiency at baseline was 65.3% (SD, 19.1) and 64.7% (SD, 17.9) for the 5 mg and 10 mg dose groups, respectively, with increases of 6.4% (95% CI, 5.1 to 7.6) and 7.3% (95% CI, 6.1 to 8.6) in both groups at 1 month. At 6 and 12 months, the 5- and 10-mg dose groups had respective increases of 11.1% and 12.6%, and 11.1% and 13.7%.
Subjective wake after sleep onset decreased 17.3 minutes (95% CI, -22.5 to -12.0) in the 5-mg group and 18.7 minutes (95% CI, -24.1 to 13.3) in the 10-mg group after 1 month, followed by decreases of 36.1 and 31.5 minutes, respectively, at 6 months. After 1 year, the 5-mg and 10-mg groups had subjective wake after sleep onset decreases of 42.9 and 43.8 minutes, respectively.
The most common adverse events reported in SUNRISE 1 and SUNRISE 2 was somnolence (10 mg, 10%; 5 mg, 7%; placebo, 1.0%). The most common adverse events leading to discontinuation of lemborexant were somnolence (10 mg, 1.0%; 5 mg, 0.7%; placebo, 0.4%) and nightmares (10 mg, 0.3%; 5 mg, 0.3%; and placebo, 0%).
In addition to effects on sleep onset latency, additional investigations found that treatment with lemborexant had no statistically significant or clinically relevant effects on next-morning driving performance.
Lynn Kramer, MD, chief clinical officer of Eisai's Neurology Business Group, expressed excitement to make a new therapy available for the millions of US insomnia patients.
"We believe the approval of Dayvigo is particularly exciting because it is the first FDA-approved medication to report safety data over a 12-month period along with sleep onset and sleep maintenance efficacy data over a six-month period in a pivotal clinical study," Kramer said in a statement.
The drug will be available early in 2020 following scheduling by the Drug Enforcement Administration.