SAN ANTONIO – results from a pooled analysis showed.
Doug Brunk/MDedge News
Dr. Margaret Moline
A dual orexin receptor antagonist developed by Eisai, lemborexant is being studied as a treatment for insomnia disorder and irregular sleep-wake rhythm disorder. Early in 2019, the Food and Drug Administration accepted for review the New Drug Application for lemborexant for the treatment of insomnia. A target Prescription Drug User Fee Act date is set for Dec. 27, 2019.
“We evaluated early on whether exposure to lemborexant was going to be different between men and women,” lead study author Margaret Moline, PhD, said during an interview at the annual meeting of the Associated Professional Sleep Societies. “With some drugs, like zolpidem and other so-called Z drugs, because exposure is different, clinical studies could involve different dosing for different sexes. Because we knew the exposure to lemborexant wasn’t different between the sexes, we expected to see similar results in both sexes. That was the case.”
Dr. Moline, executive director of the Neurology Business Group and International Project Team Lead for the lemborexant clinical development program at Eisai, and colleagues presented pooled analyses of subject-reported sleep onset latency (sSOL) and subject-reported wake after sleep onset (sWASO) from lemborexant phase 3 studies, SUNRISE-1 and SUNRISE-2. SUNRISE-1 was a 1-month, double-blind, placebo- and active-controlled, parallel-group study in 1,006 subjects. Participants were females aged 55 years and older and males aged 65 years and older with a primary complaint of sleep maintenance difficulties and an Insomnia Severity Index (ISI) total score of 13 or higher. SUNRISE-2 was a placebo-controlled, 6-month, active treatment, double-blind, parallel-group study in 949 subjects with insomnia disorder. Participants were females and males aged 18 years and older with a primary complaint of sleep onset and/or sleep maintenance difficulties and an ISI total score of 15 or higher. Both analyses included subjects randomized to placebo, lemborexant 5 mg, or lemborexant 10 mg. Each study included a single-blind placebo run-in period prior to randomization.
The pooled analysis of 1,693 subjects included 402 (23.7%) men and 1,291 (76.3%) women. Results on sSOL and sWASO were consistent with the significant results on sleep diary in the individual studies. In both sexes, sSOL for lemborexant 5 mg and lemborexant 10 mg was significantly reduced versus that for placebo during the first 7 days and end of month 1 (P less than .05 for all comparisons). In women, the researchers observed significantly greater reductions in sWASO placebo for both lemborexant doses versus that with placebo (first 7 days and end of month 1; P less than .0001 for all comparisons). In males, sWASO decreased significantly, compared with placebo, for the first 7 days (lemborexant 5 mg and lemborexant 10 mg; P equal to or less than .0001) and at end of month 1 (lemborexant 10 mg only; P = .0032). For placebo, lemborexant 5 mg, and lemborexant 10 mg, the overall incidence of treatment-emergent adverse events was similar across sexes. Incidence of treatment-emergent serious adverse events was low for both sex subgroups; most events occurred in one subject each. Treatment-emergent adverse events leading to study drug withdrawal or interruption were few and similar across sexes for all treatments and was highest in males receiving lemborexant 10 mg. The most frequent treatment-emergent adverse events reported in males were somnolence, fatigue, and headache, while the most common in females were somnolence, headache, and urinary tract infection. About 3% of females (no males) reported a urinary tract infection; the incidence in females was similar across treatment groups.
“Overall, sleep diary outcomes in males and females were consistent with the significant results observed in the total populations of the individual studies,” Dr. Moline concluded. “A dose adjustment based on sex is not anticipated.”
The research was supported by Eisai. Dr. Moline is an employee of the company.
SOURCE: Moline M et al. Sleep 2019, Abstract 0368.