Respiratory safety of lemborexant in healthy adult and elderly subjects with mild obstructive sleep apnea: A randomized, double-blind, placebo-controlled, crossover study

Respiratory safety of lemborexant in adult and elderly subjects with moderate-to-severe chronic obstructive pulmonary disease

Because some hypnotics worsen respiratory conditions, it was important to determine the respiratory safety of lemborexant, a competitive dual orexin-receptor antagonist approved to treat adults with insomnia, in subjects with moderate-to-severe chronic obstructive pulmonary disease. E2006-A001-113 (Study 113; NCT04647383) was a multicentre, multiple-dose, randomised, double-blind, placebo-controlled, two-period crossover study in adult subjects with moderate or severe chronic obstructive pulmonary disease (per spirometry-based Global Initiative for Chronic Obstructive Lung Disease [GOLD] criteria). Subjects (N = 30) were randomised to two treatment sequences comprising 8-night treatment periods (washout ≥ 14 days) with lemborexant 10 mg or placebo. Peripheral oxygen saturation (SpO2; primary endpoint), apnea-hypopnea index, objective sleep parameters and sleep architecture measures were assessed after single (Day 1) and multiple (Day 8) doses. There was no significant difference in least-squares mean SpO2 after a single dose of lemborexant (91.1%) versus placebo (91.5%). Although a statistically significant difference in SpO2 was observed after multiple doses (least-squares mean: lemborexant, 91.3%; placebo, 90.8%) favouring lemborexant, this was not considered clinically meaningful. Apnea-hypopnea index was not significantly different between treatments after single or multiple doses. Total sleep time and total rapid eye movement sleep were significantly greater on Days 1 and 8 with lemborexant versus placebo. Treatment-emergent adverse events were reported in five (16.7%) subjects when taking lemborexant and four (13.3%) subjects when taking placebo; treatment-emergent adverse events were mostly mild. Lemborexant was well tolerated and did not adversely impact SpO2 or apnea-hypopnea index after single and multiple doses relative to placebo in subjects with moderate-to-severe chronic obstructive pulmonary disease.

Clinical usefulness of dual orexin receptor antagonism beyond insomnia: Neurological and psychiatric comorbidities

Orexin is a neurotransmitter produced by a small group of hypothalamic neurons. Besides its well-known role in the regulation of the sleep-wake cycle, the orexin system was shown to be relevant in several physiological functions including cognition, mood and emotion modulation, and energy homeostasis. Indeed, the implication of orexin neurotransmission in neurological and psychiatric diseases has been hypothesized via a direct effect exerted by the projections of orexin neurons to several brain areas, and via an indirect effect through orexin-mediated modulation of sleep and wake. Along with the growing evidence concerning the use of dual orexin receptor antagonists (DORAs) in the treatment of insomnia, studies assessing their efficacy in insomnia comorbid with psychiatric and neurological diseases have been set in order to investigate the potential impact of DORAs on both sleep-related symptoms and disease-specific manifestations. This narrative review aimed at summarizing the current evidence on the use of DORAs in neurological and psychiatric conditions comorbid with insomnia, also discussing the possible implication of modulating the orexin system for improving the burden of symptoms and the pathological mechanisms of these disorders. Target searches were performed on PubMed/MEDLINE and Scopus databases and ongoing studies registered on Clinicaltrials.gov were reviewed. Despite some contradictory findings, preclinical studies seemingly support the possible beneficial role of orexin antagonism in the management of the most common neurological and psychiatric diseases with sleep-related comorbidities. However, clinical research is still limited and further studies are needed for corroborating these promising preliminary results.

Orexin Receptor Antagonism: Normalizing Sleep Architecture in Old Age and Disease

Sleep is essential for human well-being, yet the quality and quantity of sleep reduce as age advances. Older persons (>65 years old) are more at risk of disorders accompanied and/or exacerbated by poor sleep. Furthermore, evidence supports a bidirectional relationship between disrupted sleep and Alzheimer's disease (AD) or related dementias. Orexin/hypocretin neuropeptides stabilize wakefulness, and several orexin receptor antagonists (ORAs) are approved for the treatment of insomnia in adults. Dysregulation of the orexin system occurs in aging and AD, positioning ORAs as advantageous for these populations. Indeed, several clinical studies indicate that ORAs are efficacious hypnotics in older persons and dementia patients and, as in adults, are generally well tolerated. ORAs are likely to be more effective when administered early in sleep/wake dysregulation to reestablish good sleep/wake-related behaviors and reduce the accumulation of dementia-associated proteinopathic substrates. Improving sleep in aging and dementia represents a tremendous opportunity to benefit patients, caregivers, and health systems.

A randomized, double-blind, placebo-controlled, crossover study of respiratory safety of lemborexant in moderate to severe obstructive sleep apnea

STUDY OBJECTIVES

To evaluate the respiratory safety of lemborexant among adults and older adults with moderate to severe obstructive sleep apnea (OSA).

METHODS

E2006-A001-113 (Study 113; NCT04647383) was a double-blind, two-period crossover, placebo-controlled study in adults (ages ≥ 45 to ≤ 90 years, n = 33) with moderate (apnea-hypopnea index [AHI] score ≥ 15 to < 30 events/h, n = 13) or severe (AHI ≥ 30 events/h, n = 20) OSA. Participants were randomized to lemborexant 10 mg (LEM10) or placebo (PBO) for two treatment periods of 8 nights with a ≥ 14-day washout period. AHI and peripheral oxygen saturation were evaluated after treatment on Day 1 (after a single dose) and Day 8 (after multiple doses).

RESULTS

No significant differences in AHI were observed after single and multiple doses of LEM10 compared with PBO in participants with moderate to severe OSA (least-squares mean: single-dose LEM10, 41.7; PBO, 44.8; multiple-dose LEM10, 44.9; PBO, 45.7). In addition, there were no significant differences between treatments in peripheral oxygen saturation (least-squares mean: single-dose LEM10, 93.0; PBO, 93.1; multiple-dose LEM10, 93.1; PBO, 93.4). Further, there were no significant differences between treatments in percentage of total sleep time with peripheral oxygen saturation < 90%, < 85%, or < 80%. No significant differences were observed between treatments when AHI and peripheral oxygen saturation outcomes were analyzed by OSA severity. Altogether, 6/33 (18.2%) participants receiving LEM10, vs 3/33 (9.1%) PBO, reported treatment-emergent adverse events, mostly mild in severity.

CONCLUSIONS

LEM10 demonstrated respiratory safety and was well tolerated with single-dose and multiple-dose administration in participants with moderate to severe OSA. This suggests that LEM may be a treatment option for patients with OSA and comorbid insomnia.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: A Study to Evaluate the Respiratory Safety of Lemborexant in Adult and Elderly Participants With Moderate to Severe Obstructive Sleep Apnea and in Adult and Elderly Participants With Moderate to Severe Chronic Obstructive Pulmonary Disease; URL: https://clinicaltrials.gov/ct2/show/NCT04647383; Identifier: NCT04647383.

CITATION

Cheng JY, Lorch D, Lowe AD, et al. A randomized, double-blind, placebo-controlled, crossover study of respiratory safety of lemborexant in moderate to severe obstructive sleep apnea. J Clin Sleep Med. 2024;20(1):57-65.

Impact of zolpidem and lemborexant on sleep and morning symptoms when used as a single dose for polysomnography

This study evaluated the effect of zolpidem and lemborexant on sleep and morning symptoms in patients undergoing type-1 polysomnography for suspected sleep-disordered breathing based on questionnaires and polysomnography results. We enrolled 127 patients (lemborexant: N = 57, zolpidem: N = 25, without hypnotics: N = 45). Rapid eye movement sleep in patients on lemborexant was higher than that in patients without hypnotics (P = 0.02). Frequency of unsteadiness in the morning was higher in patients on zolpidem than that in patients without hypnotics (P = 0.04), which remained after adjustment for potential confounders (P = 0.03). Low-dose lemborexant might be suitable when administered as a single dose during polysomnography.

The orexin story and orexin receptor antagonists for the treatment of insomnia

Insomnia is present in up to one third of the adult population worldwide, and it can present independently or with other medical conditions such as mental, metabolic, or cardiovascular diseases, which highlights the importance of treating this multifaceted disorder. Insomnia is associated with an abnormal state of hyperarousal (increased somatic, cognitive, and cortical activation) and orexin has been identified as a key promotor of arousal and vigilance. The current standards of care for the treatment of insomnia recommend non-pharmacological interventions (cognitive behavioural therapy) as first-line treatment and, if behavioural interventions are not effective or available, pharmacotherapy. In contrast to most sleep medications used for decades (benzodiazepines and 'Z-drugs'), the new orexin receptor antagonists do not modulate the activity of γ-aminobutyric acid receptors, the main inhibitory mechanism of the central nervous system. Instead, they temporarily block the orexin pathway, causing a different pattern of effects, e.g., less morning or next-day effects, motor dyscoordination, and cognitive impairment. The pharmacokinetic/pharmacodynamic properties of these drugs are the basis of the different characteristics explained in the package inserts, including the recommended starting dose. Orexin receptor antagonists seem to be devoid of any dependence and tolerance-inducing effects, rendering them a viable option for longer-term treatment. Safety studies did not show exacerbation of existing respiratory problems, but more real-world safety and pharmacovigilance experience is needed. This review provides an overview of the orexin history, the mechanism of action, the relation to insomnia, and key features of available drugs mediating orexin signalling.

Pharmacological management of co-morbid obstructive sleep apnoea and insomnia

INTRODUCTION

Clinical presentation of both insomnia and obstructive sleep apnea (COMISA) is common. Approximately 30% of clinical cohorts with OSA have insomnia symptoms and vice versa. The underlying pathophysiology of COMISA is multifactorial. This poses a complex clinical challenge. Currently, there are no clinical guidelines or recommendations outside of continuous positive airway pressure (CPAP) therapy and cognitive behavioral therapy for insomnia (CBTi). Clinically translatable precision medicine approaches to characterize individual causes or endotypes may help optimize future pharmacological management of COMISA.

AREAS COVERED

This review article provides an up-to-date account of COMISA and its consequences, the underlying pathophysiology of sleep apnea, insomnia and COMISA, current treatment approaches and limitations, pharmacotherapy targets and future priorities.

EXPERT OPINION

There are multiple promising emerging therapies, but clinical trial data specifically in COMISA populations are lacking. This is a priority for future investigation to inform development of evidence-based guidelines. Pharmacotherapies, particularly for insomnia, do not target the underlying causes of the disorder thus, are indicated for short-term use only and should remain second line. Future multidisciplinary research should be directed toward the multifactorial nature of COMISA and the challenges of adapting COMISA treatment in clinical practice and overcoming the practical barriers that health-care providers and consumers encounter.

The Park Sleep subtype in Parkinson's disease: from concept to clinic

INTRODUCTION

The heterogeneity of Parkinson's disease (PD) is evident from descriptions of non-motor (NMS) subtypes and Park Sleep, originally identified by Sauerbier et al. 2016, is one such clinical subtype associated with the predominant clinical presentation of sleep dysfunctions including excessive daytime sleepiness (EDS), along with insomnia.

AREAS COVERED

A literature search was conducted using the PubMed, Medline, Embase, and Web of Science databases, accessed between 1 February 2023 and 28 March 2023. In this review, we describe the clinical subtype of Park Sleep and related 'tests' ranging from polysomnography to investigational neuromelanin MRI brain scans and some tissue-based biological markers.

EXPERT OPINION

Cholinergic, noradrenergic, and serotonergic systems are dominantly affected in PD. Park Sleep subtype is hypothesized to be associated primarily with serotonergic deficit, clinically manifesting as somnolence and narcoleptic events (sleep attacks), with or without rapid eye movement behavior disorder (RBD). In clinic, Park Sleep recognition may drive lifestyle changes (e.g. driving) along with therapy adjustments as Park Sleep patients may be sensitive to dopamine D3 active agonists, such as ropinirole and pramipexole. Specific dashboard scores based personalized management options need to be implemented and include pharmacological, non-pharmacological, and lifestyle linked advice.

Effects of atomoxetine plus a hypnotic on obstructive sleep apnea severity in patients with a moderately collapsible pharyngeal airway

STUDY OBJECTIVES

Pharmacotherapy for obstructive sleep apnea (OSA) regained consideration after the discovery that atomoxetine and oxybutynin greatly reduced OSA severity. However, atomoxetine and oxybutynin reduced the arousal threshold and may therefore be poorly tolerated in patients with OSA and disturbed sleep. As a result, we tested the combination of atomoxetine plus 2 hypnotics in patients with OSA. The effects of atomoxetine plus: (1) trazodone (Ato-Trazo) and (2) lemborexant vs placebo on apnea-hypopnea index, hypoxic burden, arousal threshold, and total sleep time were assessed. Drug safety was also ascertained, together with the effect of the combinations on other OSA traits, self-reported sleep quality, and next-day alertness.

METHODS

Following a baseline study, 15 patients with mild-to-severe OSA with moderate upper airway collapsibility were administered Ato-Trazo, atomoxetine and lemborexant, and matching placebo according to a double-blind, randomized, crossover design. Apnea-hypopnea index and other objective outcomes were calculated from 3 clinical, in-laboratory polysomnograms.

RESULTS

Ato-Trazo significantly reduced apnea-hypopnea index from a median [interquartile range] of 18.2 [11.8 to 31.3] on placebo to 7.4 [5.4 to 16.1] events/h, P = .024, and hypoxic burden from 46.3 [25.1 to 88.3] on placebo to 18.7 [14.9 to 43.5], P = .003. This effect was likely driven by an increase in polysomnography-estimated pharyngeal muscle activity during the events (P = .029). Atomoxetine and lemborexant had smaller statistically insignificant effects. Contrary to atomoxetine and oxybutynin, Ato-Trazo and atomoxetine and lemborexant did not reduce the arousal threshold. Both combinations had no effect on total sleep time but worsened self-reported sleep quality.

CONCLUSIONS

Ato-Trazo has the potential to become a useful drug combination, however, longer trials are needed to determine the best dosage and the subgroup of patients who may benefit most from this combination.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Crossover Trial of AD182 and AD504 in Obstructive Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/NCT04645524; Identifier: NCT04645524.

CITATION

Corser B, Eves E, Warren-McCormick J, Rucosky G. Effects of atomoxetine plus a hypnotic on obstructive sleep apnea severity in patients with a moderately collapsible pharyngeal airway. J Clin Sleep Med. 2023;19(6):1035-1042.

The abuse potential of lemborexant, a dual orexin receptor antagonist, according to the 8 factors of the Controlled Substances Act

RATIONALE

Lemborexant (LEM) is a dual orexin receptor antagonist (DORA) approved in multiple countries including the USA, Japan, Canada, Australia, and several Asian countries for the treatment of insomnia in adults. As a compound with central nervous system activity, it is important to understand the abuse potential of LEM with respect to public health.

OBJECTIVES

This review discusses data for LEM relevant to each of the 8 factors of the United States Controlled Substances Act.

RESULTS

LEM did not demonstrate abuse potential in nonclinical testing and was associated with a low incidence of abuse-related adverse events in clinical study participants with insomnia disorder. Similar to other DORAs that have been evaluated (eg., almorexant, suvorexant (SUV), and daridorexant), LEM and the positive controls (zolpidem and SUV) also showed drug liking in a phase 1 abuse potential study that enrolled subjects who used sedatives recreationally. However, internet surveillance of SUV and the FDA Adverse Events Reporting System suggests that drugs in the DORA class display very low abuse-related risks in the community. Additionally, as described in FDA-approved labeling, it does not carry physical dependence and withdrawal risks.

CONCLUSIONS

LEM, similar to most other prescription insomnia medications, was placed into Schedule IV. However, LEM and other drugs in the DORA class may have a lower potential for abuse as suggested by real-world postmarketing data from federal surveys and internet surveillance, and thus may have lower risks to public health than Schedule IV benzodiazepines and nonbenzodiazepine hypnotics that potentiate GABA signaling.

Functional roles of orexin in obstructive sleep apnea: From clinical observation to mechanistic insights

Obstructive sleep apnea is the most common sleep-related breathing disorder. Repetitive episodes of the obstructive respiratory events lead to arousal, sleep fragmentation, and excessive daytime sleepiness. Orexin, also known as hypocretin, is one of the most important neurotransmitters responsible for sleep and arousal regulation. Deficiency of orexin has been shown to be involved in the pathogenesis of narcolepsy, which shares cardinal symptoms of sleep apnea and excessive daytime sleep with obstructive sleep apnea. However, the relationship between orexin and obstructive sleep apnea is not well defined. In this review, we summarize the current evidence, from in vitro, in vivo, and clinical data, regarding the association between orexin and obstructive sleep apnea. The effects of orexin on sleep apnea, as well as how the consequences of obstructive sleep apnea affect the orexin system function are also discussed. Additionally, the contrary findings are also included and discussed.

Cost-effectiveness analysis of lemborexant for treating insomnia in Japan: a model-based projection, incorporating the risk of falls, motor vehicle collisions, and workplace accidents

BACKGROUND

Lemborexant has demonstrated statistically significant improvements in sleep onset and sleep maintenance compared with placebo and zolpidem tartrate extended release, measured both objectively using polysomnography and subjectively using sleep diaries, in the phase 3 clinical trial SUNRISE 1. This study evaluated the cost-effectiveness of lemborexant compared with suvorexant, zolpidem immediate release (IR), and untreated insomnia.

METHODS

A decision-tree model was developed for falls, motor vehicle collisions, and workplace accidents associated with insomnia and insomnia treatments from a Japanese healthcare perspective and with a 6-month time horizon. The model extracted subjective sleep onset latency treatment responses and disutility values for non-responders from SUNRISE 1. Cost-effectiveness was assessed using incremental cost per quality-adjusted life year (QALY) gained. One-way and probabilistic sensitivity analyses were conducted to evaluate the impact of parameter uncertainty on the results.

RESULTS

In the base-case analysis, the mean estimated QALYs for lemborexant, suvorexant, zolpidem-IR, and untreated insomnia were 0.4220, 0.4204, 0.4113, and 0.4163, and expected medical costs were JPY 34 034, JPY 38 371, JPY 38 139, and JPY 15 383, respectively. Lemborexant saved JPY 4337 and JPY 4105 compared with suvorexant or zolpidem-IR, respectively, while conferring QALY benefits. The incremental cost-effectiveness ratio (ICER) of lemborexant compared with that of untreated insomnia was JPY 3 220 975 /QALY. Lemborexant was dominant over suvorexant and zolpidem-IR and was cost-effective when compared with untreated insomnia. Sensitivity analyses supported the results' robustness.

CONCLUSIONS

In a Japanese clinical practice setting, lemborexant may represent a better investment for treating insomnia in the healthcare system in Japan.

Abuse potential assessment of the new dual orexin receptor antagonist daridorexant in recreational sedative drug users as compared to suvorexant and zolpidem

STUDY OBJECTIVES

Abuse potential properties have been reported for the dual orexin receptor antagonists (DORAs) suvorexant and lemborexant. Daridorexant is a new DORA currently in late-stage clinical development. This randomized, double-blind, double-dummy, placebo- and active-controlled 6-period crossover study assessed its abuse potential in healthy recreational sedative drug users (n=63).

METHODS

In each study period, a single, oral, morning dose of either daridorexant (50, 100, 150 mg), placebo, or active control, i.e., suvorexant (150 mg) or zolpidem (30 mg), was administered. Primary pharmacodynamic endpoint was the Emax of the Drug-liking visual analog scale (VAS) assessed over 24 h. Several secondary subjective and objective pharmacodynamic endpoints were also assessed.

RESULTS

Study validity was confirmed based on drug-liking of suvorexant and zolpidem greater than placebo applying a pre-defined 15-point validity margin (p<0.0001). Drug-liking VAS Emax (mean; 95% CI) of daridorexant at 50 mg (73.2; 69.0-77.5) was significantly lower compared to suvorexant (80.7; 77.0-84.5) and zolpidem (79.9; 76.2-83.5) (p<0.001), but similar at 100 mg (79.1; 75.0-83.3) and 150 mg (81.3; 77.7, 84.8). Such dose-related patterns were also observed for most secondary endpoints. At each daridorexant dose, Drug-liking VAS scores were greater than placebo. Both control drugs and daridorexant were safe and the pharmacokinetics of daridorexant was consistent with earlier trials indicating quick absorption and elimination.

CONCLUSIONS

In this large, valid human abuse potential study, daridorexant showed dose-related drug-liking among recreational sedative drug users with lower effects at the highest phase-3 dose, and similar effects at higher doses compared to supratherapeutic doses of suvorexant and zolpidem.

Current Update on Clinically Relevant Sleep Issues in Parkinson's Disease: A Narrative Review

Sleep disturbances are among the common nonmotor symptoms in patients with Parkinson’s disease (PD). Sleep can be disrupted by nocturnal motor and nonmotor symptoms and other comorbid sleep disorders. Rapid eye movement sleep behavior disorder (RBD) causes sleep-related injury, has important clinical implications as a harbinger of PD and predicts a progressive clinical phenotype. Restless legs syndrome (RLS) and its related symptoms can impair sleep initiation. Excessive daytime sleepiness (EDS) is a refractory problem affecting patients’ daytime activities. In particular, during the COVID-19 era, special attention should be paid to monitoring sleep problems, as infection-prevention procedures for COVID-19 can affect patients’ motor symptoms, psychiatric symptoms and sleep. Therefore, screening for and managing sleep problems is important in clinical practice, and the maintenance of good sleep conditions may improve the quality of life of PD patients. This narrative review focused on the literature published in the past 10 years, providing a current update of various sleep disturbances in PD patients and their management, including RBD, RLS, EDS, sleep apnea and circadian abnormalities.

Effect of the new dual orexin receptor antagonist daridorexant on nighttime respiratory function and sleep in patients with mild and moderate obstructive sleep apnea

In this randomized, double-blind, placebo-controlled, two-period crossover study, the effect of the dual orexin receptor antagonist daridorexant was evaluated on nighttime respiratory function and sleep in 28 patients with mild and moderate obstructive sleep apnea (OSA). In each period, 50 mg daridorexant or placebo was administered every evening for 5 days. The primary endpoint was apnea/hypopnea index (AHI) during total sleep time (TST) after the last dosing. Other endpoints included peripheral oxygen saturation (SpO2), sleep duration, latency to persistent sleep (LPS), wake after sleep onset (WASO), and sleep efficiency index (SEI). Pharmacokinetics, safety, and tolerability were also assessed. The mean treatment difference for AHI during TST (i.e. daridorexant - placebo) after the last dosing was 0.74 events/hour (90% confidence interval [CI]: -1.43, 2.92). The corresponding treatment difference for SpO2 during TST was 0.16% [90% CI: -0.21, 0.53]. Overall, there was no clinically relevant effect of daridorexant on AHI or SpO2-related data after single and repeated dosing irrespective of sleep phase (i.e. rapid eye movement [REM] vs non-REM). Moreover, after single and repeated dosing, daridorexant prolonged TST by 39.6 minutes (90% CI: 16.9, 62.3) and 38.8 minutes (19.7, 57.9), respectively, compared with placebo and favorably modulated other sleep-related endpoints (i.e. increased SEI, decreased WASO, and shortened LPS). It attained expected plasma concentrations and was well tolerated in patients with mild and moderate OSA. These results indicate that single and repeated doses of 50 mg daridorexant do not impair nighttime respiratory function and improve sleep in patients with mild and moderate OSA. Clinical Trial Registration: ClinicalTrials.gov NCT03765294. A study to investigate the effects of ACT-541468 on nighttime respiratory function in patients with mild to moderate obstructive sleep apnea. https://clinicaltrials.gov/ct2/show/ NCT03765294.

Insomnia: Pharmacologic Treatment

Insomnia afflicts many geriatric patients worldwide and results in both clinical and economic consequences. Prescribing hypnotics to the elderly is particularly challenging due to multitudes of adverse effects and drug interactions. Although benzodiazepines and "Z" drugs such as zolpidem have been popular in the past, they carry a high risk of adverse effects in the elderly, such as devastating falls and injuries as well as potentially an increase in mortality. Newer classes of hypnotics such as dual orexin receptor antagonists are much better tolerated and can be explored as a potential treatment for insomnia in the elderly.

Review of the Efficacy and Safety of Lemborexant, a Dual Receptor Orexin Antagonist (DORA), in the Treatment of Adults With Insomnia Disorder

OBJECTIVE

To provide an overview of the efficacy and safety of lemborexant in the treatment of insomnia disorder by assessing the currently available literature.

DATA SOURCES

A literature search of PubMed was performed (2010 to March 2021) using the following search terms: lemborexant, sleep, orexin.

STUDY SELECTION AND DATA EXTRACTION

All relevant English-language studies were reviewed and considered, with a focus on phase 3 trials.

DATA SYNTHESIS

The efficacy and safety of lemborexant in the treatment of insomnia disorder in adults was demonstrated in 2 phase 3 trials. Lemborexant significantly reduced latency to persistent sleep compared with placebo. The first study also demonstrated a significant reduction compared with the active control zolpidem ER. Somnolence and headache were relatively common, but the marked adverse effects associated with other medications commonly used to treat insomnia, such as cognitive and psychomotor impairment and complex sleep-related behaviors, were not observed.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Although nonpharmacological therapy is considered first-line treatment for insomnia disorder, pharmacological treatment is most commonly utilized. Lemborexant is a viable pharmacological treatment option for patients who are unable to tolerate the adverse effects associated with the most commonly prescribed medications for insomnia, such as benzodiazepines and sedative-hypnotics (Z drugs). This is especially true for geriatric patients, who may be more sensitive to these adverse effects.

CONCLUSION

Lemborexant can be recommended to treat insomnia disorder when pharmacological treatment is warranted. It has demonstrated efficacy in clinical trials and is likely better tolerated than most currently available treatment options.

The Insomnia-Addiction Positive Feedback Loop: Role of the Orexin System

Significant sleep impairments often accompany substance use disorders (SUDs). Sleep disturbances in SUD patients are associated with poor clinical outcomes and treatment adherence, emphasizing the importance of normalizing sleep when treating SUDs. Orexins (hypocretins) are neuropeptides exclusively produced by neurons in the posterior hypothalamus that regulate various behavioral and physiological processes, including sleep-wakefulness and motivated drug taking. Given its dual role in sleep and addiction, the orexin system represents a promising therapeutic target for treating SUDs and their comorbid sleep deficits. Here, we review the literature on the role of the orexin system in sleep and drug addiction and discuss the therapeutic potential of orexin receptor antagonists for SUDs. We argue that orexin receptor antagonists may be effective therapeutics for treating addiction because they target orexin's regulation of sleep (top-down) and motivation (bottom-up) pathways.

Evaluating lemborexant for the treatment of insomnia

INTRODUCTION

Insomnia is a complex sleep disorder that compromises quality of life and affects approximately 10% of the general population. Insomnia, defined as trouble initiating or maintaining sleep associated with impaired daytime function or distress, is treated using a comprehensive approach comprised of cognitive behavioral therapy and pharmacotherapy. Lemborexant, a dual orexin receptor antagonist, is a new pharmacotherapeutic option recently approved for the treatment of insomnia.

AREAS COVERED

Here, the authors describe lemborexant, assess its efficacy and safety profile in clinical trials, and evaluate its role in the current insomnia treatment landscape.

EXPERT OPINION

Lemborexant may offer an improved treatment option compared with other pharmacotherapies for insomnia because it is effective both over the long term and over a wide range of outcome measures. Importantly, lemborexant improves latency to sleep onset and sleep maintenance and is able to help people who experience early morning awakenings. Safety data reveal that lemborexant has minimal residual effects on morning alertness or next day function, and that patients are able to respond to an external auditory stimulus in the middle of the night. In conclusion, lemborexant represents a new, effective, and well-tolerated medication for patients with insomnia.

Respiratory Safety of Lemborexant in Healthy Subjects: A Single-Dose, Randomized, Double-Blind, Placebo-Controlled, Crossover Study

BACKGROUND AND OBJECTIVE

Lemborexant is a dual orexin receptor antagonist recently approved in the USA, Japan, and Canada for the treatment of adults with insomnia. Because some pharmacotherapy for insomnia causes respiratory depression, this study assessed the effects of lemborexant treatment on respiratory safety parameters.

METHODS

This single-dose, randomized, double-blind, placebo-controlled, three-period crossover study enrolled healthy adult and elderly subjects (n = 17). Subjects were randomized to one of three treatment sequences, each consisting of three treatment periods in which they received a single dose of placebo, lemborexant 10 mg, or lemborexant 25 mg. Each treatment period was separated by a washout period of at least 14 days. Assessments included pharmacodynamic respiratory parameters (peripheral capillary oxygen saturation (SpO₂) and apnea-hypopnea index (AHI)) and safety.

RESULTS

There were no significant differences for either dose of lemborexant versus placebo in mean peripheral capillary oxygen saturation (SpO₂; least squares mean (LSM) difference (95% confidence interval (CI)): lemborexant 10 mg, -0.36 (-0.78 to 0.07); lemborexant 25 mg, - 0.29 (- 0.72 to 0.14)) or AHI (LSM difference (95% CI): lemborexant 10 mg, 0.52 (- 1.72 to 2.76); lemborexant 25 mg, - 1.16 (- 3.40 to 1.08)) during sleep. Additionally, significant differences were not observed for the percentage of total sleep during which SpO₂ was < 85% (LSM difference (95% CI): lemborexant 10 mg, 0.004 (- 0.058 to 0.067); lemborexant 25 mg, 0.044 (- 0.018 to 0.107)) or < 80% (LSM difference (95% CI): lemborexant 10 mg, 0.001 (- 0.002 to 0.005); lemborexant 25 mg, 0.002 (-0.001 to 0.006)) for either lemborexant dose versus placebo. There was also no significant difference for lemborexant 10 mg versus placebo, for which SpO₂ was < 90% during total sleep time (LSM difference (95% CI): 0.185 (- 0.034 to 0.405)).

CONCLUSION

Overall, lemborexant at recommended doses did not have a negative effect on mean SpO₂ or AHI and was well tolerated in this cohort of healthy subjects.

Long-term effectiveness and safety of lemborexant in adults with insomnia disorder: results from a phase 3 randomized clinical trial

OBJECTIVE/BACKGROUND

Lemborexant is a dual orexin receptor antagonist approved in the United States, Japan, and Canada for the treatment of insomnia in adults. We report effectiveness and safety outcomes in subjects with insomnia who received up to twelve months of continuous lemborexant treatment in Study E2006-G000-303 (Study 303; SUNRISE-2).

PATIENTS/METHODS

Study 303 was a twelve-month, global, multicenter, randomized, double-blind, parallel-group, Phase 3 study divided into two treatment periods. In Treatment Period 1 (first six months), subjects (n = 949, Full Analysis Set) were randomized to daily placebo, lemborexant 5 mg (LEM5) or lemborexant 10 mg (LEM10). In Treatment Period 2 (second six months), placebo subjects were rerandomized to LEM5 or LEM10, and subjects randomized to lemborexant continued their assigned treatment (LEM5, n = 251; LEM10, n = 226). Sleep onset and sleep maintenance endpoints were analyzed from daily electronic sleep diary data. Treatment-emergent adverse events (TEAEs) were monitored.

RESULTS

For all sleep parameters, the significant benefits observed with LEM5 and LEM10 versus placebo over six months were maintained at twelve months in subjects who received twelve continuous months of treatment. There was no evidence of rebound insomnia or withdrawal in either lemborexant group following treatment discontinuation. Over twelve months of lemborexant treatment, most TEAEs were mild/moderate; the most common TEAEs were nasopharyngitis, somnolence and headache.

CONCLUSIONS

LEM5 and LEM10 had significant benefit on sleep onset and sleep maintenance compared with placebo, and importantly, lemborexant effectiveness persisted at twelve months, suggesting that lemborexant may provide long-term benefits for subjects with insomnia.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT02952820; ClinicalTrialsRegister.eu, EudraCT Number 2015-001463-39.

Effect of the novel dual orexin receptor antagonist daridorexant on night-time respiratory function and sleep in patients with moderate chronic obstructive pulmonary disease

In patients with chronic obstructive pulmonary disease (COPD), sleep is often fragmented while, conversely, the use of sleep medications is of concern in these patients due to potential impairment of nocturnal breathing. This randomised, double-blind, placebo-controlled, two-period crossover study was conducted to evaluate the effect of the new dual orexin receptor antagonist daridorexant on night-time respiratory function and sleep in patients with moderate COPD. In each period, the highest Phase-III dose of 50 mg daridorexant or placebo was administered once daily in the evening for 5 consecutive days. The primary endpoint was peripheral oxygen saturation (SpO₂ ) during total sleep time (TST) after last dosing. Night-time respiratory function and sleep were further evaluated based on the apnea-hypopnea index (AHI), sleep duration, and objective sleep parameters. Pharmacokinetics, safety, and tolerability were also assessed. Primary endpoint analysis revealed no significant mean treatment difference (i.e. daridorexant - placebo) for SpO₂ during TST as it was 0.18% (90% confidence interval: -0.21 to 0.57). There was also no difference from placebo for SpO₂ during non-rapid eye movement (REM) and REM sleep at Night 5 and after first dosing. The AHI was slightly increased compared to placebo, but not to a clinically meaningful extent. In addition, daridorexant improved objective sleep parameters (i.e. prolonged TST, increased sleep efficiency, and decreased wake after sleep onset), reached expected plasma concentrations, and was safe and well tolerated. In conclusion, single and multiple doses of 50 mg daridorexant do not impair night-time respiratory function and improves sleep in patients with moderate COPD.

Advances in the Treatment of Chronic Insomnia: A Narrative Review of New Nonpharmacologic and Pharmacologic Therapies

Chronic insomnia disorder, which affects 6-10% of the population, is diagnostically characterized by ongoing difficulties with initiating or maintaining sleep occurring at least three times per week, persisting for at least 3 months, and associated with daytime impairment. While chronic insomnia is often considered a condition primarily related to impaired sleep, the disorder can also adversely affect domains of physical and mental health, quality of life, and daytime function, which highlights the importance of treating the multidimensional sleep disorder. Owing to misperceptions about the safety and effectiveness of treatment options, many individuals with insomnia may not seek professional treatment, and alternatively use ineffective home remedies or over-the-counter medications to improve sleep. Some physicians may even believe that insomnia is remediated by simply having the patient "get more sleep". Unfortunately, treatment of insomnia is not always that simple. The disorder's complex underlying pathophysiology warrants consideration of different nonpharmacologic and pharmacologic treatment options. Indeed, recent insights gained from research into the pathophysiology of insomnia have facilitated development of newer treatment approaches with more efficacious outcomes. This narrative review provides a summary of the diagnostic criteria and pathophysiology of insomnia and its subtypes. Further, this review emphasizes new and emerging nonpharmacologic and pharmacologic treatments for chronic insomnia, including recent enhancements in approaches to cognitive behavioral therapy for insomnia (CBT-I) and the new dual orexin receptor antagonist (DORA) pharmacologics. These advances in treatment have expanded the treatment options and are likely to result in improved outcomes in patients with chronic insomnia.

Respiratory safety of lemborexant in healthy adult and elderly subjects with mild obstructive sleep apnea: A randomized, double-blind, placebo-controlled, crossover study

Lemborexant is a dual orexin receptor antagonist indicated for the treatment of adult and elderly individuals with insomnia. Some current pharmacologic treatments for insomnia cause respiratory depression, a serious safety concern, particularly for individuals with obstructive sleep apnea (OSA). This phase 1, randomized, double-blind, placebo-controlled, two-period crossover study examined respiratory safety parameters in individuals with mild OSA following treatment with lemborexant. Participants (n = 39) were randomized to one of two treatment sequences, including placebo and lemborexant 10 mg. Each treatment period lasted 8 days and was separated by a washout of at least 14 days. Following single or multiple doses, there were no significant differences in mean apnea-hypopnea index for lemborexant 10 mg versus placebo (least squares mean [LSM] difference [95% confidence interval {CI}]: day 1, -0.03 [-2.22, 2.17]; day 8, -0.06 [-1.95, 1.83]) or peripheral capillary oxygen saturation during sleep (LSM difference [95% CI]: day 1, 0.07 [-0.31, 0.46]; day 8, 0.25 [-0.11, 0.61]). There were no significant differences versus placebo for the percentage of total sleep time during which peripheral capillary oxygen saturation was <80% (LSM difference [95% CI]: day 1, 0.002 [-0.019, 0.023]; day 8, 0.006 [-0.015, 0.026]), <85% (LSM difference [95% CI]: day 1, 0.067 [-0.124, 0.258]; day 8, 0.056 [-0.117, 0.228]) or <90% (LSM difference [95% CI]: day 1, 0.312 [-0.558, 1.181]; day 8, 0.088 [-0.431, 0.607]). The incidence of treatment-emergent adverse events was low and similar for lemborexant and placebo. Lemborexant demonstrated respiratory safety in this study population and was well tolerated.