Daridorexant, a New Dual Orexin Receptor Antagonist to Treat Insomnia Disorder.

OBJECTIVE: To evaluate the dose-response relationship of daridorexant, a new dual orexin receptor antagonist, on sleep variables in subjects with insomnia disorder. METHODS: Adults (≤64 years) with insomnia disorder were randomized (1:1:1:1:1:1) to receive daily oral placebo, daridorexant (5, 10, 25, or 50mg), or 10mg zolpidem for 30 days. The primary efficacy outcome was the change in wake time after sleep onset from baseline to days 1 and 2. Secondary outcome measures were change in latency to persistent sleep from baseline to days 1 and 2, change in subjective wake time after sleep onset, and subjective latency to sleep onset from baseline to week 4. Safety was also assessed. RESULTS: Of 1,005 subjects screened, 359 (64% female) were randomized and received ≥1 dose. A significant dose-response relationship (multiple comparison procedure-modeling, 2-sided p < 0.001) was found in the reduction of wake after sleep onset and latency to persistent sleep from baseline to days 1 and 2 with daridorexant. These reductions were sustained through to days 28 and 29 (p = 0.050 and p = 0.042, respectively). Similar dose-dependent relationships were observed for subjective wake after sleep onset and subjective latency to sleep onset. The incidence of treatment-emergent adverse events was 35%, 38%, 38%, and 34% in subjects treated with 5, 10, 25, and 50mg daridorexant, respectively, compared with 30% for placebo, and 40% for 10mg zolpidem. There were no clinically relevant treatment-related serious adverse events. Four subjects withdrew due to adverse events. INTERPRETATION: Daridorexant induced a dose-dependent reduction in wake time after sleep onset in subjects with insomnia disorder (Clinicaltrials.gov NCT02839200). Ann Neurol 2020;87:347-356.

Meaningful Within-Patient Change in Subjective Total Sleep Time in Patients with Insomnia Disorder: An Analysis of the Sleep Diary Questionnaire Using Data from Open-Label and Phase III Clinical Trials.

BACKGROUND: The Sleep Diary Questionnaire (SDQ), a modified version of the Consensus Sleep Diary, is a 17-item sleep diary for assessing subjective total sleep time (sTST: total time spent asleep at night) and other sleep parameters in insomnia trials. sTST is a key parameter of efficacy in insomnia trials; however, the magnitude of improvement in this parameter that people with insomnia disorder consider clinically meaningful is unclear. OBJECTIVE: The aim of this study was to estimate meaningful within-patient change for sTST using clinical trial data. METHODS: Data were from an open-label trial of zolpidem and pooled data from a phase III placebo-controlled trial of daridorexant. In both trials, adults with moderate to severe insomnia completed the SDQ daily. Meaningful change in sTST was estimated in an anchor-based analysis using outcome measures that were correlated with change in weekly average sTST (Spearman correlation coefficient ≥ 0.30): the Insomnia Severity Index, patient global assessments and impressions of severity and change in daytime and night-time symptoms (PGA-S, PGI-S, PGI-C), and clinician global impressions of severity and change in patients' daytime symptoms (CGI-S, CGI-C). Meaningful within-patient change estimates were 'triangulated' to identify a value where they converged. RESULTS: In the open-label trial (N = 114), subjects with a 1-point or 1-step improvement on the anchors had mean increases in sTST of 60.1-83.2 min at day 8 and 55.5-68.2 min at day 15. For subjects with a 2-point or 2-step improvement on the anchors, mean increases in sTST were 79.6-81.4 min at day 8 and 80.1-93.5 min at day 15. In the phase III trial (N = 930), weekly average increases in sTST for subjects with a 1-point or 1-step improvement on the anchors were 39.3-46.7 min at month 1 and 47.3-58.3 min at month 3. For subjects with a 2-point or 2-step improvement on the anchors, mean increases in sTST were 60.7-76.2 min at month 1 and 70.1-87.7 min at month 3. Triangulation of these values supported a meaningful within-patient change threshold starting at 55 min. CONCLUSION: Increasing sTST is an important treatment outcome for people with insomnia. An increase in sleep time of approximately 55 min is meaningful to patients. CLINICAL TRIALS REGISTRATION: NCT03056053 (17 February 2017) and NCT03545191 (4 June 2018).

Long-Term Safety and Tolerability of Daridorexant in Patients with Insomnia Disorder.

BACKGROUND AND OBJECTIVE: Daridorexant is a dual orexin receptor antagonist for the treatment of insomnia. In two phase III, 12-week studies in patients with insomnia disorder, daridorexant improved sleep and daytime functioning while maintaining a favorable safety profile. The objective of this 40-week extension study was to assess the long-term safety and tolerability of daridorexant. METHODS: Adults with insomnia disorder who completed the 12-week studies were invited to enroll in this double-blind extension study. Patients originally randomised to daridorexant (10 mg/25 mg/50 mg) remained on their respective treatments; patients randomised to placebo were re-randomised to daridorexant 25 mg or placebo. The 40-week treatment period was followed by a 7-day placebo run-out. The primary objective was to assess safety/tolerability. Exploratory objectives were to evaluate the efficacy of daridorexant on sleep (self-reported total sleep time) and daytime functioning (Insomnia Daytime Symptoms and Impacts Questionnaire). RESULTS: In total, 804 patients were enrolled in the study, of whom 801 received at least one dose of the study treatment and 550 patients (68.4%) completed the study. Overall incidence of treatment-emergent adverse events was similar across groups (35-40%). Daridorexant did not induce next-morning sleepiness and no withdrawal-related symptoms or rebound were observed after treatment discontinuation. Improvements in sleep and daytime functioning were maintained through to the end of the study and were most pronounced with daridorexant 50 mg. Daridorexant 50 mg, compared with placebo, increased self-reported total sleep time by a least-squares mean of 20.4 (95% confidence interval [CI] 4.2, 36.5), 15.8 (95% CI - 0.8, 32.5) and 17.8 (95% CI - 0.4, 35.9) minutes and decreased (i.e., improved) Insomnia Daytime Symptoms and Impacts Questionnaire total scores by a least-squares mean of - 9.3 (95% CI - 15.1, - 3.6), - 9.5 (95% CI - 15.4, - 3.5) and - 9.1 (95% CI - 15.6, - 2.7), at weeks 12, 24 and 36 of the extension study, respectively. CONCLUSIONS: Treatment with daridorexant, for up to 12 months, was generally safe and well tolerated. Exploratory efficacy analyses suggest that the sustained improvements in sleep and daytime functioning with daridorexant 50 mg support its use for long-term treatment of insomnia disorder, without concerns of new safety signals. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT03679884) [first posted: 21 September, 2018], https://clinicaltrials.gov/ct2/show/NCT03679884 .

Insomnia disorder is the long-term inability to fall asleep or stay asleep with a significant impact on daily life. Left inadequately treated, this disorder may increase the risk of other health problems. For patients with insomnia disorder who require a sleep medication, many drugs are not recommended for long-term use and there is an unmet need for one that can be used safely and effectively over the long term. Daridorexant is a new insomnia treatment that was approved for adults following positive results in two 12-week clinical studies. Both studies showed that, in patients with insomnia disorder, daridorexant improved night-time sleep and patients' ability to function during the day, while avoiding major safety concerns. Patients who completed these two studies could continue into a 40-week extension study enabling the safety and tolerability of daridorexant to be investigated for up to 1 year. Treatment remained double blind for the entire 1-year period. The extension study showed that daridorexant, at all doses studied (10 mg, 25 mg, 50 mg), continued to be generally safe and well tolerated. Patients showed no signs of tolerance, physical dependence, rebound nor any excessive daytime sleepiness. Exploratory efficacy analyses suggest that improved night-time and daytime symptoms of insomnia were sustained, in particular with the highest approved dose, 50 mg, and there were no signs that the benefits of the drug were wearing off at the end of the 1 year. These results support the use of daridorexant 50 mg for the long-term treatment of insomnia disorder in adults.

Number, Duration, and Distribution of Wake Bouts in Patients with Insomnia Disorder: Effect of Daridorexant and Zolpidem.

BACKGROUND: Daridorexant, a dual orexin receptor antagonist approved in early 2022, reduces wake after sleep onset without reducing the number of awakenings in patients with insomnia. The objective of this post hoc analysis was to explore the effect of daridorexant on the number, duration, and distribution of night-time wake bouts, and their correlation with daytime functioning. METHODS: Adults with insomnia disorder were randomized 1:1:1:1:1:1 to placebo, zolpidem 10 mg, or daridorexant 5, 10, 25, or 50 mg in a phase II dose-finding study, and 1:1:1 to placebo or daridorexant 25 or 50 mg in a pivotal phase III study. We analyzed polysomnography data for daridorexant 25 and 50 mg, zolpidem 10 mg, and placebo groups. Polysomnography was conducted at baseline, then on Days 1/2, 15/16, and 28/29 in the phase II study, and Months 1 and 3 in the phase III study. The number, duration, and distribution of wake bouts (≥ 0.5 min) were assessed. RESULTS: Data from 1111 patients (phase II study: daridorexant 50 mg [n = 61], zolpidem 10 mg [n = 60], placebo [n = 60]; phase III study: daridorexant 25 mg [n = 310], daridorexant 50 mg [n = 310], placebo [n = 310]) were analyzed. Long wake bouts were defined as > 6 min. Compared with placebo, daridorexant 50 mg reduced overall wake time (p < 0.05; all time points, both studies), the odds of experiencing long wake bouts (p < 0.001; Months 1 and 3, phase III study), and the cumulative duration of long wake bouts (p < 0.01; all time points, both studies). Reductions in long wake bouts were sustained through the second half of the night and correlated with improvements in daytime functioning. An increase in the cumulative duration of short wake bouts was observed with daridorexant 50 mg (p < 0.01 vs placebo, Months 1 and 3, phase III study); this was uncorrelated with daytime functioning. CONCLUSION: Daridorexant reduced the number and duration of longer wake bouts throughout the night compared with placebo, corresponding with improved daytime functioning. CLINICAL TRIALS: Clinicaltrials.gov NCT02839200 (registered July 20, 2016), NCT03545191 (registered June 4, 2018).

Preferences of patients for benefits and risks of insomnia medications using data elicited during two phase III clinical trials.

STUDY OBJECTIVES: To elicit the trade-offs patients are willing to make between benefits and risks of medications for chronic insomnia, with the purpose of allowing a patient-centric interpretation of clinical trial data. METHODS: A discrete choice experiment (DCE) was included in the two placebo-controlled phase III trials that evaluated the efficacy and safety of daridorexant. The DCE design was informed by a two-phase qualitative study, followed by qualitative and quantitative pilot testing before fielding. Relative attribute importance (RAI) and acceptable trade-offs between benefits and risks were obtained using a mixed logit model. RESULTS: Preferences were elicited from 602 trial participants (68.1% female, aged 58.6 ± 14.5 years). Preferences were most affected by daytime functioning (RAI = 33.7%) as a treatment benefit and withdrawal symptoms (RAI = 27.5%) as a risk. Patients also valued shorter sleep onset (RAI = 6.4%), longer sleep maintenance (RAI = 5.4%), reduced likelihood of abnormal thoughts and behavioral changes (RAI = 11.3%), reduced likelihood of dizziness/grogginess (RAI = 9.2%), and reduced likelihood of falls at night (RAI = 6.5%). Patients were willing to make trade-offs between these attributes. For example, they would accept an additional 18.8% risk of abnormal thoughts and behavioral changes to improve their daytime functioning from difficult to restricted and an additional 8.1% risk of abnormal thoughts and behavioral changes to avoid moderate withdrawal effects. CONCLUSIONS: Patients with insomnia were willing to make trade-offs between multiple benefits and risks of pharmacological treatments. Because patients valued daytime functioning more than sleep latency and duration, we recommend that functional outcomes and sleep quality be considered in treatment development and evaluation.

Efficacy and Safety of Daridorexant in Older and Younger Adults with Insomnia Disorder: A Secondary Analysis of a Randomised Placebo-Controlled Trial.

BACKGROUND AND OBJECTIVE: The dual orexin receptor antagonist daridorexant, studied in two phase III trials, dose-dependently improved objective and subjective sleep variables and daytime functioning in adults with insomnia. Because treatment of insomnia in older adults is challenging and has limited options, the purpose of the current analysis was to further analyse the phase III trial studying the higher doses of daridorexant, those that showed efficacy (daridorexant 50 mg, daridorexant 25 mg and placebo, nightly for 3 months), and compare the safety and efficacy of daridorexant in patients aged ≥ 65 ('older adults') to those aged < 65 years ('younger adults'). METHODS: Analyses by age (≥ 65 years, n = 364; < 65 years, n = 566) were performed on data from the randomised, double-blind, placebo-controlled Trial 1 in adult patients with insomnia (NCT03545191). Efficacy endpoints included a change from baseline at month 1 and month 3 in polysomnography-measured wake after sleep onset (WASO) and latency to persistent sleep (LPS), self-reported total sleep time (sTST) and daytime functioning assessed using the validated Insomnia Daytime Symptoms and Impacts Questionnaire (IDSIQ). Safety endpoints included adverse events and the Visual Analog Scale for morning sleepiness. RESULTS: At baseline, mean [standard deviation] WASO was numerically greater (110 [39] vs 92 [38] min) in older than younger adults, while LPS was comparable (~ 65 min). Mean baseline IDSIQ total and all domain scores were numerically lower (i.e. better) in older adults. Daridorexant caused similar reductions in WASO and LPS, and similar increases in sTST, from baseline, in both age groups; improvements were numerically greater with daridorexant 50 mg than 25 mg. At month 3, daridorexant 50 mg, compared with placebo, decreased WASO by a least-squares mean of 19.6 (95% confidence interval 9.7, 29.5) in older patients versus 17.4 min (10.7, 24.0) in younger patients and decreased LPS by a least-squares mean of 14.9 (7.5, 22.3) in older patients versus 9.7 min (3.7, 15.7) in younger patients. Daridorexant 50 mg increased sTST from baseline to month 3 by a least-squares mean of 59.9 (49.6, 70.3) in older patients versus 57.1 min (48.9, 65.3) in younger patients. Daridorexant 50 mg progressively improved IDSIQ total and domain scores from week 1 onwards similarly in both groups; daridorexant 25 mg improved IDSIQ scores, but only in younger adults. In both age groups, in comparison with placebo, the overall incidence of adverse events was comparable, and there were fewer falls on daridorexant. Daridorexant improved Visual Analog Scale morning sleepiness in both groups; daridorexant 50 mg increased the mean (standard deviation) Visual Analog Scale morning sleepiness score by 15.9 (20.7) in older adults and by 14.9 (18.7) in younger adults from baseline to month 3. In older adults, there was one case of sleep paralysis, and no cases of narcolepsy, cataplexy, or complex sleep behaviour. CONCLUSIONS: In older patients with insomnia, as in younger patients, the efficacy of daridorexant is maximal on night-time and daytime variables at the higher dose of 50 mg. Older patients particularly require this dose to improve daytime functioning. Older patients are not at an increased risk of adverse events or residual effects the next morning after night-time administration of daridorexant, even at 50 mg. The dose of daridorexant does not need to be decreased for older patients. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT03545191) [first posted: 4 June, 4 2018], https://clinicaltrials.gov/ct2/show/NCT03545191 .

The burden of chronic insomnia (difficulty in falling/staying asleep or not getting enough sleep) increases with age yet treatment options in older patients are limited. In older patients, because of a risk of side effects, guidelines suggest caution when prescribing sleep medications and, for some drugs, recommend starting at a lower dose. Daridorexant was approved in 2022 for the treatment of insomnia in adults following positive results in two trials that showed daridorexant significantly improved night-time sleep and daytime functioning over 3 months of treatment in adults with insomnia. Approximately 40% of patients taking part in these trials were aged 65 years or older. This current analysis compared the safety and benefits of daridorexant in older adults (aged at least 65 years) and younger adults (aged less than 65 years) in the trial that administered the highest two doses of daridorexant, 25 and 50 mg. The results showed that the benefits of daridorexant were comparable in both age groups over 3 months; compared with placebo, daridorexant improved night-time sleep (reduced time awake during the night, reduced time to fall asleep and increased total sleep time) and daytime functioning­patients had less daytime sleepiness and a better mood and feeling of alertness. In older patients, the benefits, particularly for daytime functioning, were greatest at the higher 50-mg dose, without any increase in side effects. Both doses of daridorexant were equally well tolerated in the two age groups, indicating that treatment with daridorexant at 50 mg can be safely started in older patients.

Development and Validation of the Insomnia Daytime Symptoms and Impacts Questionnaire (IDSIQ).

BACKGROUND AND OBJECTIVE: Chronic insomnia has major consequences for daytime functioning, yet no fully validated patient-reported outcome instrument for once-daily assessments is available to measure these consequences. This study describes the development and psychometric evaluation of the Insomnia Daytime Symptoms and Impacts Questionnaire (IDSIQ). METHODS: The Daytime Insomnia Symptom Scale (DISS), an existing 20-item instrument for assessing daytime functioning, was modified to give an 18-item version of the IDSIQ (IDSIQ-18) based on iterative qualitative interviews with 54 subjects with insomnia and expert input. The construct validity and other psychometric properties of the IDSIQ-18 were analyzed based on an interventional study (NCT03056053) in which subjects with insomnia received zolpidem (5 or 10 mg) daily for 2 weeks and an observational study among subjects with no diagnosis of insomnia (good sleepers). Participants in both studies completed the IDSIQ-18 daily for 2 weeks. Exit interviews were conducted with a sample of subjects who completed the interventional study to elicit concepts defining the experience of insomnia, to assess understanding of the response scales, and to determine meaningful change thresholds. Exploratory factor analysis and Rasch analysis were conducted to further assess the structure and latent model for the scoring of the final IDSIQ instrument. Further psychometric evaluation of the final IDSIQ was then conducted. RESULTS: Subjects in both the interventional study (N = 114) and observational study (N = 103) were predominantly female (65% for subjects with insomnia and 60% for good sleepers). Mean age was 51 years for subjects with insomnia and 45 years for good sleepers. Subjects in the exit interviews (N = 41) demonstrated a good understanding of the IDSIQ-18 response scales. Day 1 mean scores were higher (worse) in subjects with insomnia compared with good sleepers. Based on inter-item correlation, exploratory factor, and Rasch analyses and review of the qualitative data, four items were removed. This yielded the final IDSIQ, with 14 items comprising three domains: Alert/Cognition, Mood, and Sleepiness. The domain structure was determined in a confirmatory factor analysis. Evidence of internal consistency reliability was strong: day 1 Cronbach's alpha was 0.917 for IDSIQ total score and 0.806-0.918 for the domains. Test-retest reliability, assessed for subjects with insomnia with no change on the Patient Global Assessment of Disease Severity scale between day 1 and day 8, was also good (intra-class correlation coefficient 0.856-0.911). Meaningful change thresholds derived for this sample using anchor-based approaches were 20 for IDSIQ total score, 9 for the Alert/Cognition domain, 4 for the Mood domain, and 4 for the Sleepiness domain. CONCLUSIONS: These studies, which closely followed Food and Drug Administration Guidance for Industry on patient-reported outcome measures, support use of the IDSIQ as a fit-for-purpose measure for deriving valid and reliable endpoints in insomnia clinical research trials and real-world studies.