Rationale: Novel compound with potent antagonistic activity against orexin receptors may be new treatment option for patients with insomnia.

Objective: The aim was to investigate the efficacy and safety of single oral doses of the dual orexin receptor antagonist TS-142 in patients with insomnia.

Methods: This multicenter, double-blind, crossover randomized clinical trial included non-elderly patients with insomnia. Patients were randomized to receive single doses of placebo and TS-142 at doses of 5, 10, and 30 mg in one of four different sequences, with a 7-day washout period between treatments. Primary efficacy endpoints were latency to persistent sleep (LPS) and wake time after sleep onset (WASO) measured by polysomnography.

Results: Twenty-four patients were included (mean age 50.3 ± 10.5 years; mean duration of insomnia 5.71 ± 8.68 years). Least-squares mean differences (95% confidence interval) from placebo in LPS with 5, 10, and 30 mg TS-142 were - 42.38 (- 60.13, - 24.63), - 42.10 (- 60.02, - 24.17), and - 44.68 (- 62.41, - 26.95) minutes, respectively (all p < 0.001). Least-squares mean differences (95% confidence interval) from placebo in WASO with 5, 10, and 30 mg TS-142 were - 27.52 (- 46.90, - 8.14), - 35.44 (- 55.02, - 15.87), and - 54.69 (- 74.16, - 35.23) minutes, respectively (all p < 0.01). Self-reported aspects of sleep initiation and sleep quality, determined using the Leeds Sleep Evaluation Questionnaire (LSEQ), were also improved with TS-142 administration versus placebo. TS-142 was well tolerated; all adverse events were mild or moderate and none were serious.

Conclusion: Single-dose TS-142 was well tolerated and had clinically relevant effects on objective and subjective sleep parameters in patients with insomnia.

Clinical Trial Registration: JapicCTI173570 (www.

Clinicaltrials: jp); NCT04573725 (www.

Clinicaltrials: gov).

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.

Background: Seltorexant is a potent and selective antagonist of the orexin-2 receptor that is being developed for the treatment of insomnia and major depressive disorder.

Aims: The primary objective was to investigate the effect of seltorexant on sleep efficiency after single and multiple dose administration in subjects with insomnia disorder without psychiatric comorbidity. Secondary objectives included evaluation of total sleep time, latency to persistent sleep, and wake after sleep onset. Subjects received 40 mg of seltorexant for five days during Period 1 and placebo during Period 2 or vice versa in this randomized, two-way crossover study. Objective sleep parameters were evaluated by polysomnography over 8 h on Day 1/2 (single dose) and on Day 5/6 (multiple doses). Subjective sleep parameters were assessed by questionnaires.

Results: Twenty-seven subjects completed the study. The mean changes in sleep efficiency (% (SD)) of seltorexant from placebo at Day 1/2 were 5.8 (9.2), and 7.9 (9.8) at Day 5/6 ( p < 0.001 at both time points); in total sleep time (min (SD)) 27.7 (44.3) and 37.9 (47.1), respectively; in latency to persistent sleep (min (SD)) -18.8 (21.3) and -29.9 (27.7), respectively; and in wake after sleep onset (min (SD)) -11.1 (36.4) and -11.3 (46.5). The most common adverse events were headache and somnolence.

Conclusions: Sleep efficiency was increased with seltorexant treatment compared with placebo. Treatment with seltorexant resulted in a prolonged total sleep time, shorter latency to persistent sleep and wake after sleep onset. There were no unexpected safety findings.

Objective: To assess the utility of orexin receptor antagonism as a novel approach to treating insomnia.

Methods: We evaluated suvorexant, an orexin receptor antagonist, for treating patients with primary insomnia in a randomized, double-blind, placebo-controlled, 2-period (4 weeks per period) crossover polysomnography study. Patients received suvorexant (10 mg [n = 62], 20 mg [n = 61], 40 mg [n = 59], or 80 mg [n = 61]) in one period and placebo (n = 249) in the other. Polysomnography was performed on night 1 and at the end of week 4 of each period. The coprimary efficacy end points were sleep efficiency on night 1 and end of week 4. Secondary end points were wake after sleep onset and latency to persistent sleep.

Results: Suvorexant showed significant (p values <0.01) dose-related improvements vs placebo on the coprimary end points of sleep efficiency at night 1 and end of week 4. Dose-related effects were also observed for sleep induction (latency to persistent sleep) and maintenance (wake after sleep onset). Suvorexant was generally well tolerated.

Conclusions: The data suggest that orexin receptor antagonism offers a novel approach to treating insomnia.

Classification Of Evidence: This study provides Class I evidence that suvorexant improves sleep efficiency over 4 weeks in nonelderly adult patients with primary insomnia.

Insomnia is one of the most common and burdensome disorders in adults. We compared and ranked insomnia medication on the basis of their efficacy and tolerability. We performed a systematic review and network meta-analysis of placebo-controlled or head-to-head randomized controlled trials for primary insomnia in adults comparing 20 drugs. We searched eight databases and seven trial registers from inception to March 1st, 2022. Primary outcomes included sleep latency (SL), awake time after sleep onset (WASO) and discontinuation for adverse events (AED), and secondary outcomes included total sleep time (TST), sleep efficiency (SE), sleep quality (SQ) and adverse events (ADE). Pooled standardized mean differences or odds ratios with 95% credible intervals were estimated using pairwise and network meta-analysis with random-effects. Differences among trial findings were explored in subgroup and sensitivity analyses. Confidence in evidence was assessed using GRADE. The PROSPERO registered number is CRD42020182144. We identified 22,538 records and included 69 studies (17,319 patients). Orexin receptor antagonists (ORAs) are more efficacious than benzodiazepine-like drugs (Z-drugs) and placebo for WASO and SE, and better than melatonin receptor agonists (MRAs) for SL, WASO and SE. ORAs ranked the best in SL (SUCRA value: 0.84), WASO (0.93), TST (0.86) and SE (0.96). Lemborexant and daridorexant (two ORAs) showed greater efficacy than placebo for SL, WASO, and TST, with good tolerability. Z-drugs were more efficacious than placebo for SL, WASO, TST and SE, but with higher risk to safety. Zaleplon and eszopiclone had better efficacy than placebo for TST and SQ respectively. MRAs may also be efficacious for sleep-onset insomnia with good safety. However, the long-term adverse effects of all medications are unclear. Insomnia medications differ in their efficacy and tolerability. ORAs have superior efficacy and tolerability. These findings should aid clinicians in matching risk/benefits of drugs available in their countries to insomnia symptoms.

Orexin (hypocretin)–containing neurons in the lateral hypothalamus stimulate wake-promoting nuclei in the brainstem and hypothalamus and inhibit sleep-promoting nuclei in the ventrolateral and median preoptic areas. Conversely, inhibiting orexinergic neurotransmission inhibits wakefulness and promotes sleep. Three dual orexin receptor antagonists — suvorexant, lemborexant, and daridorexant — are FDA-approved for insomnia. Clinical trials support their efficacy for sleep-onset and sleep-maintenance symptoms. Side effects include sedation, fatigue, and abnormal dreaming, but they produce less cognitive impairment than benzodiazepine receptor agonists. Because a deficiency in endogenous orexin causes narcolepsy with cataplexy, orexin antagonists are contraindicated in patients with this condition.

Orexin (hypocretin)–containing neurons in the lateral hypothalamus stimulate wake-promoting nuclei in the brainstem and hypothalamus and inhibit sleep-promoting nuclei in the ventrolateral and median preoptic areas. Conversely, inhibiting orexinergic neurotransmission inhibits wakefulness and promotes sleep. Three dual orexin receptor antagonists — suvorexant, lemborexant, and daridorexant — are FDA-approved for insomnia. Clinical trials support their efficacy for sleep-onset and sleep-maintenance symptoms. Side effects include sedation, fatigue, and abnormal dreaming, but they produce less cognitive impairment than benzodiazepine receptor agonists. Because a deficiency in endogenous orexin causes narcolepsy with cataplexy, orexin antagonists are contraindicated in patients with this condition.

Rationale: Novel compound with potent antagonistic activity against orexin receptors may be new treatment option for patients with insomnia.

Objective: The aim was to investigate the efficacy and safety of single oral doses of the dual orexin receptor antagonist TS-142 in patients with insomnia.

Methods: This multicenter, double-blind, crossover randomized clinical trial included non-elderly patients with insomnia. Patients were randomized to receive single doses of placebo and TS-142 at doses of 5, 10, and 30 mg in one of four different sequences, with a 7-day washout period between treatments. Primary efficacy endpoints were latency to persistent sleep (LPS) and wake time after sleep onset (WASO) measured by polysomnography.

Results: Twenty-four patients were included (mean age 50.3 ± 10.5 years; mean duration of insomnia 5.71 ± 8.68 years). Least-squares mean differences (95% confidence interval) from placebo in LPS with 5, 10, and 30 mg TS-142 were - 42.38 (- 60.13, - 24.63), - 42.10 (- 60.02, - 24.17), and - 44.68 (- 62.41, - 26.95) minutes, respectively (all p < 0.001). Least-squares mean differences (95% confidence interval) from placebo in WASO with 5, 10, and 30 mg TS-142 were - 27.52 (- 46.90, - 8.14), - 35.44 (- 55.02, - 15.87), and - 54.69 (- 74.16, - 35.23) minutes, respectively (all p < 0.01). Self-reported aspects of sleep initiation and sleep quality, determined using the Leeds Sleep Evaluation Questionnaire (LSEQ), were also improved with TS-142 administration versus placebo. TS-142 was well tolerated; all adverse events were mild or moderate and none were serious.

Conclusion: Single-dose TS-142 was well tolerated and had clinically relevant effects on objective and subjective sleep parameters in patients with insomnia.

Clinical Trial Registration: JapicCTI173570 (www.

Clinicaltrials: jp); NCT04573725 (www.

Clinicaltrials: gov).

Background: Insomnia is a common sleep disorder that is diagnosed primarily by patients' subjective reported symptoms. Daridorexant is a new dual orexin receptor antagonist that was recently approved by Food and Drug Administration for insomnia characterized by difficulty falling asleep and/or maintaining sleep. MECHANISM OF ACTION, PHARMACODYNAMICS,

And Pharmacokinetics: The orexin neuropeptide signaling system plays a role in wakefulness, and blocking the wake-promoting neuropeptides results in diminished wake signaling, thus exerting a sedative effect using an entirely different mechanism of action than the classical sleep promoting agents. The drug has quick onset of action, high volume of distribution, and high protein binding. Pharmacokinetics and pharmacodynamic parameters were similar in patients of different sex and age and were not significantly affected by race, body size, or mild-to-moderate kidney impairment. Dose limitation to 25 mg in moderate liver impairment and no use in severe liver impairment are recommended. The drug undergoes hepatic CYP3A4 metabolism; thus, caution with strong CYP3A4 inhibitors and inducers is warranted.

Clinical Trials: The drug was approved based on phase 3 trials involving study 1 and study 2. Study 1 noted daridorexant at doses of 25 and 50 mg demonstrated a statistically significant improvement in wake time after sleep onset, latency to persistent sleep, and self-reported total sleep time against placebo at months 1 and 3. Similarly in study 2, compared with placebo, the 25 mg dose demonstrated statistically significant improvement in wake time after sleep onset, latency to persistent sleep, and self-reported total sleep time at months 1 and 3. Treatment-emergent adverse events were similar for daridorexant and placebo, with nasopharyngitis and headache most frequently reported.

Therapeutic Advance: Daridorexant is a novel agent with demonstrated efficacy in sleep onset and maintenance and decrease in daytime sedation. Preliminary results from a 1-year extension study note similar incidences of mild-to-moderate side effects as noted in previous trials. Further studies are needed to establish its place in the pharmacological treatment of insomnia.

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.

Objective: To assess the utility of orexin receptor antagonism as a novel approach to treating insomnia.

Methods: We evaluated suvorexant, an orexin receptor antagonist, for treating patients with primary insomnia in a randomized, double-blind, placebo-controlled, 2-period (4 weeks per period) crossover polysomnography study. Patients received suvorexant (10 mg [n = 62], 20 mg [n = 61], 40 mg [n = 59], or 80 mg [n = 61]) in one period and placebo (n = 249) in the other. Polysomnography was performed on night 1 and at the end of week 4 of each period. The coprimary efficacy end points were sleep efficiency on night 1 and end of week 4. Secondary end points were wake after sleep onset and latency to persistent sleep.

Results: Suvorexant showed significant (p values <0.01) dose-related improvements vs placebo on the coprimary end points of sleep efficiency at night 1 and end of week 4. Dose-related effects were also observed for sleep induction (latency to persistent sleep) and maintenance (wake after sleep onset). Suvorexant was generally well tolerated.

Conclusions: The data suggest that orexin receptor antagonism offers a novel approach to treating insomnia.

Classification Of Evidence: This study provides Class I evidence that suvorexant improves sleep efficiency over 4 weeks in nonelderly adult patients with primary insomnia.

Systematic comparisons of the doses of the Food and Drug Administration (FDA)-approved dual orexin receptor antagonists (DORAs) for people with insomnia are limited. PubMed, Embase, Cochrane Library, and Clinicaltrials. gov were systematically searched to identify relevant studies published before 31 October 2022. We assessed the certainty of evidence using the confidence in network meta-analysis (CINeMA) framework. We pooled 7257 participants from 9 randomized controlled trials (RCTs). Moderate to high certainty evidence demonstrated suvorexant (20 and 40 mg) and daridorexant (10 and 50 mg) as the most effective in latency to persistent sleep (LPS) reduction. Lemborexant at 5 and 10 mg was the most effective in subjective sleep onset time (sTSO) reduction. For wake time after sleep onset (WASO), all drugs except daridorexant 5 mg were more effective than placebo. Lemborexant 5 mg was among the best in subjective WASO (sWASO) (moderate to high certainty) and had the highest surface under the curve ranking area (SUCRA) values for sWASO (100%). For total sleep time (TST), suvorexant and daridorexant, except the respective minimum doses, were more effective than placebo, while suvorexant 40 mg and lemborexant 10 mg may have been the most effective for subjective TST (sTST) (low to very low certainty). Suvorexant 40 mg (RR 1.09), suvorexant 80 mg (RR 1.65), and daridorexant 25 mg (RR 1.16) showed a higher safety risk than placebo. Suvorexant 20 mg, lemborexant 5 mg, lemborexant 10 mg, and daridorexant 50 mg represent suitable approaches for insomnia. clinicaltrials.gov, PROSPERO (CRD42022362655).