The Burden of Narcolepsy Disease (BOND) study: health-care utilization and cost findings

REM sleep in narcolepsy

Narcolepsy is mainly associated with excessive daytime sleepiness, but the characteristic feature is abnormal rapid eye movement (REM) sleep phenomena. REM sleep disturbances can manifest as cataplexy (in narcolepsy type 1), sleep paralysis, sleep-related hallucinations, REM sleep behavior disorder, abnormal dreams, polysomnographic evidence of REM sleep disruption with sleep-onset REM periods, and fragmented REM sleep. Characterization of REM sleep and related symptoms facilitates the differentiation of narcolepsy from other central hypersomnolence disorders and aids in distinguishing between narcolepsy types 1 and 2. A circuit comprising regions within the brainstem, forebrain, and hypothalamus is involved in generating and regulating REM sleep, which is influenced by changes in monoamines, acetylcholine, and neuropeptides. REM sleep is associated with brainstem functions, including autonomic control, and REM sleep disturbances may be associated with increased cardiovascular risk. Medications used to treat narcolepsy (and REM-related symptoms of narcolepsy) include stimulants/wake-promoting agents, pitolisant, oxybates, and antidepressants; hypocretin agonists are a potential new class of therapeutics. The role of REM sleep disturbances in narcolepsy remains an area of active research in pathophysiology, symptom management, and treatment. This review summarizes the current understanding of the role of REM sleep and its dysfunction in narcolepsy.

A qualitative exploration of the lived experience of mothers caring for a child with narcolepsy

STUDY OBJECTIVES

Parents/carers of a child with narcolepsy are often required to become experts in narcolepsy and navigate health care, education, and welfare systems on behalf of their child. Managing pediatric narcolepsy is complex and challenges the child and the entire family, yet few studies have explored carers' experiences.

METHODS

Twenty mothers (50% had a child with narcolepsy < 18 years at the time of interview; 85% narcolepsy with cataplexy) participated in a 1:1 semistructured interview. Participation from fathers was sought; however, none were recruited. A multidisciplinary team of researchers/clinicians analyzed interview transcripts using thematic analysis.

RESULTS

Mothers perceived that most people misunderstood the whole-person impact of narcolepsy, including their child's peers, teachers, and support networks. Narcolepsy had a substantial psychological impact on both the child and the whole family yet was largely unaddressed by health care professionals, leaving mothers unsure of where to turn for help. Most parents described negative experiences with their child's specialist, often perceiving the specialists to lack knowledge specific to narcolepsy. Information about illness trajectory and support services was limited or inaccessible, fueling many mothers' hopes and fears for their child's future. Mothers also frequently described feelings of abandonment by the health care system.

CONCLUSIONS

Our results contextualize the whole-person impact of narcolepsy from the perspective of parents and carers, highlighting the need for proactive inclusion of parents/carers in developing health care policy and practice. It calls for developing tools and resources to capture "well-managed" narcolepsy from the perspective of parents/carers for use in research and clinical practice.

CITATION

Schokman A, Cheung J, Klinner C, et al. A qualitative exploration of the lived experience of mothers caring for a child with narcolepsy. J Clin Sleep Med. 2024;20(5):699-707.

Making sense of narcolepsy: A qualitative exploration of how persons with narcolepsy perceive symptoms and their illness experience

INTRODUCTION

Understanding how persons with narcolepsy conceptualize symptoms, daily impact and illness experience is key to facilitating dialogue between patients and healthcare professionals. These concepts are usually explored from the perspective of healthcare professionals/researchers and rarely from the perspective of those with narcolepsy.

METHODS

127 self-reported persons with narcolepsy were recruited from an Australian patient support group. A short demographic survey was completed. All agreed to participate in a subsequent 1:1 semi-structured interview. Saturation was reached after 24 interviews (mean age = 33 years (SD 11) with 44% reporting cataplexy). A multidisciplinary team of researchers/clinicians analyzed interview transcripts using thematic analysis.

RESULTS

Participants perceived physical fatigue, sleepiness, and two separate experiences of 'falling asleep/sleep attacks' as distinct symptoms rather than a multidimensional construct (i.e. excessive daytime sleepiness). We also identified two experiences of cataplexy, one triggered by acute emotion and another by a stressor. Participants determined their narcolepsy to be 'well-managed' by the level of functional impairment rather than the frequency of any symptom. Almost all participants described experiencing anticipated stigma and internalized or 'self-' stigma, likely stemming from societal devaluation of sleep and the conflation of sleepiness with laziness.

CONCLUSION

Descriptions of common symptoms often differed between participants and the existing literature. These differences likely impact patient-physician communication, with both parties utilizing the same terminology to communicate different concepts. The characterization of stigma in narcolepsy presents opportunities for future research exploring the impact and possible development of interventions to reduce the substantial psychological comorbidity in persons with narcolepsy.

Burden of narcolepsy in Japan: A health claims database study evaluating direct medical costs and comorbidities

OBJECTIVE

This study aimed to determine the burden of narcolepsy in terms of direct medical costs and comorbidities and compare it with the respective burden of schizophrenia, epilepsy, and ulcerative colitis as controls.

METHODS

Patients diagnosed with narcolepsy (at least once based on the International Statistical Classification of Diseases and Related Health Problems, 10th Revision, code G47.4) between April 2017 and March 2022 were identified on the health insurance claims database compiled by JMDC Inc. Patients with schizophrenia (F20), epilepsy (G40), and ulcerative colitis (K51) were matched as controls. Direct medical costs (including inpatient, outpatient, and medication costs) and comorbidities were analyzed.

RESULTS

We identified 4,594 patients with narcolepsy (≥18 years), 18,376 with schizophrenia, 18,376 with epilepsy, and 4,594 with ulcerative colitis. The total annual direct medical cost per person with narcolepsy was 349,188 JPY. The cost for narcolepsy was less than that for schizophrenia, epilepsy, and ulcerative colitis. Several comorbidities, such as sleep apnea, attention deficit hyperactivity disorder (ADHD), and obesity were more prevalent in the narcolepsy group.

CONCLUSIONS

The total direct cost for narcolepsy was approximately three times higher than the national medical expense for people aged 15-44 years (122,000 JPY in 2020), but lower than the total cost for all control diseases. The patients with narcolepsy were also likely to have comorbidities that affected their burden. These findings can contribute to future discussions on medical expense assistance programs for patients with narcolepsy.

Efficacy of once-nightly sodium oxybate (FT218) in narcolepsy type 1 and type 2: post hoc analysis from the Phase 3 REST-ON Trial

STUDY OBJECTIVES

Post hoc analyses from the phase 3 REST-ON trial evaluated efficacy of extended-release once-nightly sodium oxybate (ON-SXB; FT218) vs placebo for daytime sleepiness and disrupted nighttime sleep in narcolepsy type 1 (NT1) and 2 (NT2).

METHODS

Participants were stratified by narcolepsy type and randomized 1:1 to ON-SXB (4.5 g, week 1; 6 g, weeks 2-3; 7.5 g, weeks 4-8; and 9 g, weeks 9-13) or placebo. Assessments included mean sleep latency on Maintenance of Wakefulness Test (MWT) and Clinical Global Impression-Improvement (CGI-I) rating (coprimary endpoints) and sleep stage shifts, nocturnal arousals, and patient-reported sleep quality, refreshing nature of sleep, and Epworth Sleepiness Scale (ESS) score (secondary endpoints) separately in NT1 and NT2 subgroups.

RESULTS

The modified intent-to-treat population comprised 190 participants (NT1, n = 145; NT2, n = 45). Significant improvements were demonstrated with ON-SXB vs placebo in sleep latency for NT1 (all doses, p < .001) and NT2 (6 and 9 g, p < .05) subgroups. Greater proportions of participants in both subgroups had CGI-I ratings of much/very much improved with ON-SXB vs placebo. Sleep stage shifts and sleep quality significantly improved in both subgroups (all doses vs placebo, p < .001). Significant improvements with all ON-SXB doses vs placebo in refreshing nature of sleep (p < .001), nocturnal arousals (p < .05), and ESS scores (p ≤ .001) were reported for NT1 with directional improvements for NT2.

CONCLUSIONS

Clinically meaningful improvements of a single ON-SXB bedtime dose were shown for daytime sleepiness and DNS in NT1 and NT2, with less power for the limited NT2 subgroup.

Long-Term Treatment of Narcolepsy and Idiopathic Hypersomnia with Low-Sodium Oxybate

Narcolepsy and idiopathic hypersomnia are chronic conditions that negatively affect alertness, mental and physical energy, functioning, and quality of life (QoL). Calcium, magnesium, potassium, and sodium oxybates (low-sodium oxybate; LXB) is an oxybate formulation with 92% less sodium than sodium oxybate (SXB; a treatment for narcolepsy) and the same active moiety. LXB is approved in the US for treatment of cataplexy or excessive daytime sleepiness (EDS) in patients 7 years of age or older with narcolepsy, and idiopathic hypersomnia in adults. In Phase 3 clinical trials, LXB exhibited a safety profile consistent with that of SXB in narcolepsy. Besides continued efficacy in treating symptoms, potential benefits of long-term LXB treatment include flexible optimization of dosing and regimen, improvement of QoL and functioning, weight loss, and (relative to SXB in narcolepsy) health benefits of reduced sodium content. Dosing of LXB is twice nightly (for narcolepsy) or once or twice nightly (for idiopathic hypersomnia) based on patient characteristics and response, and individualized titration can be leveraged over the long term as a patient's life circumstances change. Patients with narcolepsy transitioning from SXB initiate LXB at the same dose, and most patients require no further changes to achieve similar efficacy and tolerability. Improvements in functioning and QoL with LXB treatment could have cascading positive effects in multiple domains, particularly in younger patients. In clinical trials, LXB was associated with weight loss in both narcolepsy (in which obesity is a well-established comorbidity) and idiopathic hypersomnia, only occasionally leading participants to be underweight. As both narcolepsy and idiopathic hypersomnia are associated with increased risk of cardiometabolic and cardiovascular comorbidities, limiting medication-related sodium intake with LXB may have significant health benefits, although this has not yet been verified prospectively due to the prolonged follow-up required. LXB is a promising long-term treatment for narcolepsy and idiopathic hypersomnia.

Pharmacological options for narcolepsy: are they the way forward?

INTRODUCTION

Narcolepsy is an under-recognized, rare neurologic disorder of hypersomnolence that is associated with increased mortality and medical and psychiatric co-morbidities. Narcolepsy exerts a substantial economic burden on patients and society. There is currently no cure, and life-long symptomatic therapy is needed. Available drugs do not modify the disease course.

AREAS COVERED

This manuscript provides an overview of narcolepsy symptoms, diagnosis, pathophysiology, current pharmacotherapies, and emerging treatments. Gaps and unresolved issues in diagnosis and management of narcolepsy are discussed to answer whether pharmacological options are the way forward.

EXPERT OPINION

Diagnostic criteria for narcolepsy (ICSD-3) need revision and greater clarity. Improved recognition of cataplexy and other symptoms through educational outreach, new biomarkers, improved test scoring through artificial intelligence algorithms, and use of machine learning may facilitate earlier diagnosis and treatment. Pharmacological options need improved symptomatic therapy in addition to targeted therapies that address the loss of hypocretin signaling. Optimal narcolepsy care also needs a better understanding of the pathophysiology, recognition of the different phenotypes in narcolepsy, identification of at-risk individuals and early recognition of symptoms, better diagnostic tools, and a database for research and disease monitoring of treatment, side-effects, and comorbidities.

Narcolepsy and Idiopathic Hypersomnia

Narcolepsy types 1 and 2 and idiopathic hypersomnia are primary Central Nervous System (CNS) disorders of hypersomnolence characterized by profound daytime sleepiness and/or excessive sleep need. Onset of symptoms begins typically in childhood or adolescence, and children can have unique presentations compared with adults. Narcolepsy type 1 is likely caused by immune-mediated loss of orexin (hypocretin) neurons in the hypothalamus; however, the causes of narcolepsy type 2 and idiopathic hypersomnia are unknown. Existing treatments improve daytime sleepiness and cataplexy but there is no cure for these disorders.

Resilience and its correlates in patients with narcolepsy type 1

STUDY OBJECTIVES

This study aimed to explore resilience and its possible association with sociodemographic and clinical features in patients with narcolepsy type 1 (NT1).

METHODS

This was a cross-sectional study involving patients with NT1 and age-/sex-matched controls (comparison group). Sociodemographic and clinical data were collected through semistructured interviews and validated questionnaires, including the Epworth Sleepiness Scale (ESS), State-Trait Anxiety Inventory (STAI)-State Anxiety, Beck Depression Inventory (BDI), 36-item Short Form Survey (SF-36), and the Resilience Scale (RS). Different statistical approaches were used to investigate the relationship between resilience and NT1 and associations with sociodemographic and clinical features.

RESULTS

The participants comprised 137 patients (mean age, 38.0 years; 52.6% female) and 149 controls (39.6 years; 55.7% female). Compared with controls, patients had a significantly lower (122.6 vs 135.5) mean RS score and a 2-fold risk of having low/mild-range resilience (adjusted odds ratio = 1.99, 95% confidence interval 1.13-3.52). Patients with high resilience had sociodemographic and narcolepsy characteristics similar to patients with low resilience, but they reported anxiety and depressive symptomatology less frequently (4.2% vs 55.8% and 58.3%, respectively), and their SF-36 scores were comparable to those of the comparison group. In patients, RS score was strongly associated with STAI-State Anxiety and BDI (rho = -0.57 and -0.56, respectively) and weakly with ESS (rho = -20) scores.

CONCLUSIONS

The results of this study suggest that resilience may play a key role in patients' adaptation to NT1. Furthermore, this study supports interventions aimed at increasing patients' resilience and provides a base for further studies, preferably longitudinal and including objective measures, directed toward understanding the relationship between resilience, depression, and quality of life in patients with narcolepsy.

CITATION

D'Alterio A, Menchetti M, Zenesini C, et al. Resilience and its correlates in patients with narcolepsy type 1. J Clin Sleep Med. 2023;19(4):719-726.

Long-term safety and maintenance of efficacy of sodium oxybate in the treatment of narcolepsy with cataplexy in pediatric patients

STUDY OBJECTIVES

Evaluate long-term efficacy and safety of sodium oxybate (SXB) in children and adolescents (aged 7-16 years) with narcolepsy with cataplexy.

METHODS

A double-blind randomized withdrawal study was conducted. Prior to randomization, SXB-naive participants were titrated to an efficacious and tolerable dose of SXB; participants taking SXB entered on their established dose. Following a 2-week stable-dose period and 2-week, double-blind, randomized withdrawal period, participants entered an open-label period (OLP; ≤ 47 weeks). Efficacy measures during the OLP included number of weekly cataplexy attacks, cataplexy-free days, and Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD). Safety outcomes included treatment-emergent adverse events; assessments of depression, anxiety, and suicidality; and polysomnography.

RESULTS

Of 106 enrolled participants, 95 entered and 85 completed the OLP. In SXB-naive participants and participants previously taking SXB, efficacy of SXB established prior to the double-blind, randomized withdrawal period was maintained throughout the OLP for number of weekly cataplexy attacks (median [quartile 1, quartile 3] change from the stable-dose period to end of the OLP: 0.0 [-2.5, 4.9] and 0.0 [-3.4, 2.6], respectively) and ESS-CHAD scores (0.0 [-3.0, 2.5] and 1.0 [-3.0, 3.0], respectively). The median (quartile 1, quartile 3) number of cataplexy-free days per week was 2.3 (0.0, 6.0) in OLP week 1 and 3.8 (0.5, 5.5) in week 48. Treatment-emergent adverse events (≥ 5%) were enuresis, nausea, vomiting, headache, decreased weight, decreased appetite, nasopharyngitis, upper respiratory tract infection, and dizziness.

CONCLUSIONS

SXB demonstrated long-term maintenance of efficacy in pediatric narcolepsy with cataplexy, with a safety profile consistent with that observed in adults.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: A Multicenter Study of the Efficacy and Safety of Xyrem with an Open-Label Pharmacokinetic Evaluation and Safety Extension in Pediatric Subjects with Narcolepsy with Cataplexy; URL: https://clinicaltrials.gov/ct2/show/NCT02221869; Identifier: NCT02221869.

CITATION

Lecendreux M, Plazzi G, Dauvilliers Y, et al. Long-term safety and maintenance of efficacy of sodium oxybate in the treatment of narcolepsy with cataplexy in pediatric patients. J Clin Sleep Med. 2022;18(9):2217-2227.

Demographic and Clinical Correlates of Narcolepsy in Adolescents Hospitalized with Mood Disorders: A Nationwide Inpatient Sample (NIS) Study

OBJECTIVES

To discern the differences in demographic, clinical comorbidities, and hospital outcomes associated with narcolepsy in adolescents hospitalized for mood disorders.

METHODS

We included 639,064 adolescents hospitalized with mood disorders, that is, major depressive disorder (MDD) and bipolar disorders (BP) from the nationwide inpatient sample. About 0.04% of inpatients had comorbid narcolepsy (N = 267) and we extracted a demographically matched control group (N = 270) for comparison.

RESULTS

Mood-disordered adolescents with narcolepsy had a higher prevalence of comorbid obesity (18.5% in BP,14.4% in MDD) and sleep apnea (9.3% in BP, 9.6% in MDD) compared to those without narcolepsy. Obesity and sleep apnea were significantly more prevalent in Black adolescents hospitalized for MDD and BP (P < .001). There was a higher percentage of females with BP and comorbid narcolepsy than males (59.9% vs 40.1%). In comparison, MDD and comorbid narcolepsy were observed more in males (57.1% vs 42.9%).

CONCLUSIONS

Our study results suggest a significantly higher prevalence of obesity and sleep apnea comorbidity in mood-disordered adolescents with narcolepsy with an overall negative impact on hospital outcomes.

How patient centric is health policy development? The case of the Parliamentary Inquiry into Sleep Health Awareness in Australia

Objective Parliamentary inquiries into health-related issues empower everyday Australians to contribute to the development and reform of health policy. We explored how patient and family/carers concerns are translated by this process, using a less well-known disease, narcolepsy, as an example. Methods Written submissions made to the Parliamentary Inquiry into Sleep Health Awareness in Australia 2018 by self-identified patients or family/carers with narcolepsy (n  = 13) were extracted and thematically analysed using the Framework Approach. Each submission was systematically coded and abstracted into emergent themes before being evaluated against the final policy recommendations. Results Although patients and their family/carers prioritised issues that affected their daily lives (i.e. mental health sequela, workplace accommodations), the policy recommendations in the report focused mainly on issues of healthcare infrastructure, funding and engagement. Our analysis highlighted several barriers that patients and their family/carers face when contributing to this part of healthcare policy formation. Conclusions Our findings suggest that the parliamentary inquiry process in its current form is not an ideal vehicle by which patients and family/carers can contribute or influence healthcare policy. Despite calling for submissions from patients and their family/carers, the final report and subsequent health policy recommendations made by the inquiry do not appear to be patient-centric or reflective of the submissions written by these stakeholders. Increased transparency, development of processes to balance stakeholder priorities and improved accessibility for stakeholders to participate are needed if health-related parliamentary inquiries are to produce healthcare policy that ultimately meets the needs of patients and family/carers.

Prevalence, incidence, and health care utilization of patients with narcolepsy: a population-representative study

STUDY OBJECTIVES

Previous estimated prevalence of narcolepsy in Europe was 47 patients per 100,000 persons, with a yearly incidence of 0.64-1.37 per 100,000. However, analyses of representative datasets from large cohorts are limited. This study aimed to estimate the population-based diagnostic prevalence and incidence of narcolepsy in Germany, and to describe these patients and their health care resource utilization.

METHODS

This study used the InGef research database, an anonymized representative dataset of 4 million persons covered by statutory health insurance in Germany. Patients with confirmed narcolepsy diagnoses in 2018 were included. Mid-p exact tests were used to calculate 95%-confidence intervals. Patients with narcolepsy diagnoses and narcolepsy-targeting therapy in 2014-2018 were included to describe health care resource utilization in the year prior to diagnosis.

RESULTS

In 2018 diagnostic prevalence was estimated as 17.88 (95%-CI 16.45-19.40), and 12-month incidence as 0.79 (0.52-1.15) per 100,000 persons. 46% patients were in psycho-behavioral therapeutic treatment and 61% of employees had sick-leave days. One in three patients was hospitalized for any cause. 28% received antibiotics.

CONCLUSIONS

Diagnostic prevalence was lower, but incidence was consistent with previous reports, though previous estimates may diverge in terms of age/gender-distributions. Patients showed a substantial utilization of health care resources, including sick leave and hospitalization. Almost half the patients underwent psycho-behavioral treatment in the year prior to diagnosis, which might indicate high burden of psychiatric symptoms. The increased use of antibiotics could indicate more frequent infections than in the general population.

Current Understanding of Narcolepsy 1 and its Comorbidities: What Clinicians Need to Know

Narcolepsy is a chronic neurologic disorder associated with the dysregulation of the sleep–wake cycle that often leads to a decreased quality of life and results in a considerable health burden. There is often a delay to diagnosis of narcolepsy, mainly due to the lack of recognition of this disorder. One of the main factors hindering the diagnosis of narcolepsy is the association of comorbidities, which include other sleep disorders, psychiatric disorders, cardiovascular disorders, and metabolic disorders. The signs and symptoms of these comorbidities often overlap with those of narcolepsy, and some of the medications used for their treatment may obscure the symptoms of narcolepsy, leading to a delay in diagnosis. This review is targeted to clinicians unaccustomed to working with sleep disorders and aims to increase recognition and improve the management of narcolepsy.

Development of a lower-sodium oxybate formulation for the treatment of patients with narcolepsy and idiopathic hypersomnia

INTRODUCTION

Sodium oxybate (SXB) is a standard of care for cataplexy, excessive daytime sleepiness, and disrupted nighttime sleep in narcolepsy. At recommended dosages in adults (6-9 g/night), SXB increases daily dietary intake of sodium by 1100-1640 mg. Because excess sodium intake is associated with increased blood pressure and cardiovascular risk, an oxybate formulation containing 92% less sodium than SXB (lower-sodium oxybate; LXB) was developed to provide an alternative oxybate treatment option. In 2020, LXB was approved for treatment of cataplexy or excessive daytime sleepiness in patients 7 years of age and older with narcolepsy, and in 2021, for treatment of idiopathic hypersomnia in adults.

AREAS COVERED

Development of LXB from initial concept to regulatory approval is described, including formulation development and preclinical and clinical studies. Pharmacokinetic parameters and bioequivalence evaluations from phase 1 clinical trials are detailed. Efficacy and safety results from phase 3 clinical trials of LXB in patients with narcolepsy or idiopathic hypersomnia are presented and discussed.

EXPERT OPINION

Reducing sodium from high sodium‒containing medications is an important step to offset cardiovascular risks associated with high sodium consumption. The development of LXB exemplifies the importance of a collaborative approach to drug development, with patient needs paramount.

PLAIN LANGUAGE SUMMARY

Sodium oxybate (Xyrem®) is a medication for people with narcolepsy aged 7 years and older. Xyrem treats symptoms of excessive daytime sleepiness (EDS) or cataplexy (attacks of muscle weakness caused by emotion) in narcolepsy. At the recommended dosages in adults, Xyrem adds a large amount of sodium to daily dietary intake. Too much sodium in the diet is associated with increased blood pressure and risks of damage to the heart and blood vessels. Researchers used calcium, magnesium, and potassium ions in addition to a small amount of sodium to make a new oxybate medication, called Xywav®, that has 92% less sodium than Xyrem. Xywav and Xyrem were similar in laboratory and animal studies. In people, the body absorbs and processes Xywav slightly differently than Xyrem, but Xywav treatment has been shown to work the same to reduce symptoms of cataplexy and EDS in people with narcolepsy and is approved by the US Food and Drug Administration. Another neurological disorder with EDS is called idiopathic hypersomnia. Based on a clinical study, Xywav also reduced EDS and other symptoms in people with idiopathic hypersomnia. Side effects with Xywav are similar to those seen in previous studies with Xyrem.

Assessing the impact of sodium oxybate treatment on functioning, productivity, and health-related quality of life in patients with narcolepsy: findings from the Nexus Narcolepsy Registry (waves 1-4)

BACKGROUND

The aim of this study was to evaluate the impact of different therapy regimens, including sodium oxybate (SXB)-containing regimens, on patient-reported outcomes (PROs) in people with narcolepsy.

METHODS

Online surveys were used to collect information from persons with narcolepsy in the Nexus Narcolepsy Registry. Surveys contained questionnaires assessing self-reported sleep quality (SQ; via single question), daytime sleepiness and function (Epworth Sleepiness Scale and Functional Outcomes of Sleep Questionnaire), health-related quality of life (HRQoL; 36-Item Short Form Health Survey [SF-36]), work productivity and impairment (Work Productivity and Activity Impairment: Specific Health Problem), and history of injuries or motor vehicle accidents. Treatment with SXB (including monotherapy or combination therapy; SXB group) was compared with non-SXB therapy (No SXB group). The P values presented are nominal, as there are no adjustments for multiplicity.

RESULTS

From June 2015 through December 2017, 983 participants completed 1760 surveys. SQ and daytime functioning scores were better in the SXB group compared with the No SXB group (all P < 0.001). HRQoL scores were better for the SXB group compared with the No SXB group for the SF-36 Physical Component (P = 0.016), Mental Component (P < 0.001), and all 8 subscales. Additionally, PROs were better for the SXB group for presenteeism, overall work and activity impairment, and risk of motor vehicle accidents (all P ≤ 0.001).

CONCLUSION

Based on participants' self-assessments, treatment regimens with SXB were associated with better outcomes than regimens not containing SXB across many PROs, including SQ, HRQoL, work and activities, and risk of traffic accidents. CLINICALTRIALS.

GOV IDENTIFIER

NCT02769780.

The Nexus Narcolepsy Registry: methodology, study population characteristics, and patterns and predictors of narcolepsy diagnosis

OBJECTIVE/BACKGROUND

The real-world experience of people with narcolepsy is not well understood.

PATIENTS/METHODS

The Nexus Narcolepsy Registry (NCT02769780) is a longitudinal, web-based patient registry of self-reported data from adults with physician-diagnosed narcolepsy. Surveys were electronically distributed every 6 months; the current analysis reports registry population demographics, narcolepsy diagnosis journey, and predictors of diagnostic delays.

RESULTS

The registry population included in this analysis (N = 1024) was predominantly female (85%) and White (92%), with a mean age of 37.7 years. Most participants had education/training beyond high school (93%). Mean (median) reported ages at narcolepsy symptom onset, first consultation for symptoms, and narcolepsy diagnosis were 18.1 (16), 26.4 (24), and 30.1 (28) years, respectively. A majority (59%) of participants reported ≥1 misdiagnosis, and 29% reported consulting ≥5 physicians before narcolepsy diagnosis. More than half (56%) of participants' first consultations for narcolepsy symptoms were with a general practitioner, whereas the diagnosing clinician was usually a sleep specialist (64%) or neurologist (27%). Pediatric symptom onset was associated with a longer mean interval to first consultation than adult symptom onset (10.7 and 4.6 years, respectively; P < 0.001) and a longer mean interval between first consultation and diagnosis (4.5 and 2.2 years, respectively; P < 0.001). Overall, mean (95% CI) time from symptom onset to diagnosis was 11.8 (11.1-12.5) years.

CONCLUSIONS

The Nexus Narcolepsy Registry data indicate that onset of narcolepsy symptoms frequently occurs in childhood or adolescence. In many individuals, the diagnostic process is long and involves multiple physicians and frequent misdiagnosis.

Narcolepsy: A clinical review

ABSTRACT

Narcolepsy continues to be a significantly underdiagnosed/misdiagnosed condition worldwide. According to the National Institutes of Health (NIH), an estimated 135,000 to 200,000 patients in the United States are living with narcolepsy. However, due to the number of patients who either do not seek medical advice for their symptoms or receive an incorrect initial diagnosis at onset, this number may be higher. This article reviews the different subtypes of narcolepsy along with the pathophysiology, screening guidelines, clinical features, diagnosis, and management of the disorder. Educational awareness from a healthcare and patient standpoint can enhance early detection and accurate diagnosis of narcolepsy and improve patient quality of life.

Developing a cognitive behavioral therapy for hypersomnia using telehealth: a feasibility study

STUDY OBJECTIVES

The purpose of this study was to evaluate the feasibility and acceptability of a novel cognitive behavioral therapy for hypersomnia (CBT-H) in people with central disorders of hypersomnolence and co-occurring depressive symptoms using a telehealth model for delivery and assessment.

METHODS

Thirty-five adults with narcolepsy or idiopathic hypersomnia received a 6-session CBT-H delivered individually or in small groups using videoconferencing. The clinical impact of CBT-H was evaluated using the Patient Health Questionnaire, Patient-Reported Outcomes Measurement Information System measures, Epworth Sleepiness Scale, and other patient-reported outcomes collected online at baseline and posttreatment. Feasibility and acceptability of the intervention and telehealth model was also evaluated using qualitative data collected from exit interviews conducted through videoconferencing.

RESULTS

Forty percent of the sample achieved a clinically significant baseline to posttreatment change in depressive symptoms (decrease in Patient Health Questionnaire ≥ 5), which is below the prespecified efficacy benchmark (50% of the sample). The prespecified benchmark for a minimal clinically important difference (Cohen's d > 0.5) on other psychosocial measures was met only on the Patient-Reported Outcomes Measurement Information System global self-efficacy (d = 0.62) in the total sample. Qualitative data revealed enthusiasm for the accessibility of telehealth delivery and the usefulness of several cognitive and behavioral modules but also revealed opportunities to refine the CBT-H program.

CONCLUSIONS

These findings indicate that this new CBT-H program can potentially reduce depressive symptoms and improve self-efficacy in people with central disorders of hypersomnolence. Furthermore, telehealth is a promising model for remote delivery and data collection to enhance participant accessibility and engagement.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Psychosocial Adjunctive Treatment for Hypersomnia (PATH); URL: https://clinicaltrials.gov/ct2/show/NCT03904238; Identifier: NCT03904238.

Evaluation of the abuse potential of pitolisant, a selective H3-receptor antagonist/inverse agonist, for the treatment of adult patients with narcolepsy with or without cataplexy

Objectives

To evaluate the human abuse potential of pitolisant, a selective histamine 3 (H₃)-receptor antagonist/inverse agonist recently approved by the US Food and Drug Administration for the treatment of excessive daytime sleepiness in adult patients with narcolepsy.

Methods

Nondependent, recreational stimulant users able to distinguish phentermine HCl 60 mg from placebo in a drug discrimination test were randomized in a four-period, double-blind, crossover design to receive single doses of pitolisant 35.6 mg (therapeutic dose), pitolisant 213.6 mg (supratherapeutic dose), phentermine HCl 60 mg, and placebo. The primary endpoint was maximum effect (E_max) on the 100-point Drug Liking (“at this moment”) visual analog scale.

Results

In 38 study completers (73.7% male; 65.8% white; mean age, 33.3 years), mean Drug Liking E_max was significantly greater for phentermine versus pitolisant 35.6 mg (mean difference, 21.4; p < 0.0001) and pitolisant 213.6 mg (mean difference, 19.7; p < 0.0001). Drug Liking E_max was similar for pitolisant (both doses) and placebo. Similarly, for key secondary measures of Overall Drug Liking and willingness to Take Drug Again, mean E_max scores were significantly greater for phentermine versus pitolisant (both doses) and similar for pitolisant (both doses) versus placebo. The incidence of adverse events was 82.1% after phentermine HCl 60 mg, 72.5% after pitolisant 213.6 mg, 47.5% after pitolisant 35.6 mg, and 48.8% after placebo administration.

Conclusions

In this study, pitolisant demonstrated significantly lower potential for abuse compared with phentermine and an overall profile similar to placebo; this suggests a low risk of abuse for pitolisant.

Clinical Trial Registration

ClinicalTrials.gov NCT03152123. Determination of the abuse potential of pitolisant in healthy, nondependent recreational stimulant users. https://clinicaltrials.gov/ct2/show/NCT03152123.

How Does Narcolepsy Impact Health-Related Quality of Life? A Mixed-Methods Study

Study Objectives: The purpose of this study was to identify patient-centered issues affecting Health-Related Quality of Life (HRQoL) in people with narcolepsy (PWN) and to evaluate patient-reported outcome measures using a mixed-methods approach. Methods: Twenty-nine adults (93% female, mean age = 31 years) with an established diagnosis of narcolepsy (Type I = 58.6%) completed focus group interviews using live videoconferencing. Additionally, participants completed the Patient-Reported Outcomes Measurement Information System (PROMIS) measures along with legacy measures commonly used in narcolepsy research (Epworth Sleepiness Scale, Patient Health Questionnaire, Short-Form 36). Results: Thematic analysis of qualitative data revealed that HRQoL was impacted by the constancy of sleepiness, unpredictability of narcolepsy symptoms, and negative public perception of narcolepsy. Challenges to accessibility and/or quality of care included dissatisfaction with non-sleep specialists' understanding of narcolepsy, the unpredictability of symptoms, and the cost of health care. There was enthusiasm for developing a psychosocial intervention to improve HRQoL using online access, but there were mixed opinions regarding the format, provider background, and content of the intervention. Elevations (T-score > 60) were found on PROMIS measures of depression, anxiety, fatigue, and sleep impairment. These patterns were consistent with the levels reported on legacy measures. PWN Type I reported lower levels of general health relative to Type II (p < .05). Conclusions: These findings lay the groundwork for more targeted efforts to address areas of diminished HRQoL in PWN. Additionally, PROMIS measures appear to be suitable and efficient instruments for assessing HRQoL in PWN.

The Xyrem® (Sodium Oxybate) Risk Evaluation and Mitigation Strategy (REMS) Program in the USA: Results From 2016 to 2017

BACKGROUND

Sodium oxybate, which is approved for the treatment of cataplexy or excessive daytime sleepiness in patients with narcolepsy, is available in the USA only through the restricted-distribution Xyrem^® Risk Evaluation and Mitigation Strategy Program (Xyrem REMS Program, XRP). The XRP requires prescriber enrollment and certification, patient enrollment, and prescriber attestation of patient counseling. Sodium oxybate is dispensed only by the certified pharmacy. After pharmacist/patient counseling, sodium oxybate is shipped only to enrolled patients, with documentation of safe use. Documentation of enrollments, prescriptions, counseling, shipments, and adverse events in a central database, and risk management reporting of any suspicion of abuse, misuse, or diversion, ensure provider notification and facilitate monitoring.

OBJECTIVE

This analysis reports data from the XRP regarding assessment of the risks of serious adverse outcomes that may result from inappropriate prescribing, abuse, misuse, and diversion.

METHODS

Data collected from December 2016 to December 2017 were analyzed.

RESULTS

Prescriptions were from enrolled prescribers (n = 4524); 17,037 patients received one or more shipment of sodium oxybate. No patients were shipped sodium oxybate under more than one name/identifier or after being disenrolled; no individual patient had overlapping active prescriptions. Sodium oxybate was dispensed in 146,426 shipments containing 375,173 bottles; of those, 13 shipments (0.009%) and 26 bottles (0.007%) were lost in delivery and not recovered. Notifications regarding potential abuse (n = 31), misuse (n = 343), or diversion (n = 22) were discussed with prescribers. Most patients and prescribers were aware of the main safety risks of sodium oxybate.

CONCLUSIONS

The XRP maintains controlled access to sodium oxybate; additional prescriber education on safety risks may be warranted.

Recognizing the Symptom Spectrum of Narcolepsy to Improve Timely Diagnosis: A Narrative Review

Narcolepsy is a chronic sleep disorder with a strong negative impact on quality of life, especially when untreated. Diagnostic delay is a persistent problem, with obvious detrimental effects on patients. A diagnosis of narcolepsy may be delayed because of its broad symptom presentation which is much more encompassing than the classical "tetrad" of sleepiness, cataplexy, hallucinations, and sleep paralysis. Furthermore, symptoms can vary over time. Presentation of symptoms can also be markedly different between children and adults. Finally, common sleep-related comorbidities increase the risk of narcolepsy being masked by overlapping symptoms or treatment. In this review, we provide a detailed description of the broad and dynamic symptom spectrum of narcolepsy, with specific attention to the different manifestations in both adults and children. The overarching goal is to help not only sleep specialists, but general practitioners, pediatricians, and other caregivers with early recognition and prompt diagnosis of this severe but treatable disorder.

Reviewing the Clinical Implications of Treating Narcolepsy as an Autoimmune Disorder

Narcolepsy type 1 (NT1) is a lifelong sleep disorder, primarily characterized clinically by excessive daytime sleepiness and cataplexy and pathologically by the loss of hypocretinergic neurons in the lateral hypothalamus. Despite being a rare disorder, the NT1-related burden for patients and society is relevant due to the early onset and chronic nature of this condition. Although the etiology of narcolepsy is still unknown, mounting evidence supports a central role of autoimmunity. To date, no cure is available for this disorder and current treatment is symptomatic. Based on the hypothesis of the autoimmune etiology of this disease, immunotherapy could possibly represent a valid therapeutic option. However, contrasting and limited results have been provided so far. This review discusses the evidence supporting the use of immunotherapy in narcolepsy, the outcomes obtained so far, current issues and future directions.

[Advances in treatment of narcolepsy]

Narcolepsy is the most common cause of excessive daytime sleepiness (EDS) following obstructive sleep apnea. Its treatment aims to reduce EDS and cataplexy, improve nighttime sleep disturbance, sleep paralysis and sleep-related hallucinations. Pitolisant (a histamine H3 receptor antagonist) and solriamfetol (a norepinephrine reuptake inhibitor) have recently been approved effective for narcolepsy in the United States and the European Union. Pitolisant has proved to be effective for both EDS and cataplexy. Besides being effective on EDS, solriamfetol seems to have advantages in abuse potential and withdrawal syndrome. As potential treatments for EDS and cataplexy associated with narcolepsy, several new drugs are being developed and tested. These new drugs include new hydroxybutyrate preparations (controlled release sodium hydroxybutyrate FT218, low sodium hydroxybutyrate JZP-258), selective norepinephrine reuptake inhibitor (AXS-12), and modafinil combined with astroglial junction protein inhibitor (THN102). This paper reviews the recently approved drugs and potential treatments for narcolepsy.

LC-MS/MS method for the quantification of SUVN-G3031, a novel H3 receptor inverse agonist for narcolepsy treatment

Background: A LC-MS/MS method was validated for the quantification of SUVN-G3031, a novel H3 receptor inverse agonist in clinical development for the treatment of patients with narcolepsy, with and without cataplexy. Methodology: SUVN-G3031 was extracted from plasma following acetonitrile protein precipitation, separated by Ultra HPLC and quantified using positive ESI-MS/MS. Results: The method was linear across the range of 0.1-100 ng ml^-1 in plasma. Results for intra and inter-day accuracy were from 99.8 to 104% and precision (%CV) was ≤10.6%. Conclusion: The method was applied to a first-in-human study in healthy volunteers. The method is precise, accurate and highly selective for the quantification of SUVN-G3031 in human plasma.

Prevalence and incidence of narcolepsy in a US health care claims database, 2008-2010

STUDY OBJECTIVES

To determine the prevalence and incidence of narcolepsy using a large US health care claims database.

METHODS

The Truven Health MarketScan Commercial Dissertation Database (THMCDD) was used to estimate prevalence and incidence of narcolepsy, with and without cataplexy, by age groups, gender, and region among patients under age 66 years with continuous enrollment for years 2008-2010. THMCDD contains health claims information for more than 18 million people. Prevalence was expressed as cases/100 000 persons. Average annual incidence (using varying criteria for latency between the diagnostic tests, polysomnograph coupled with multiple sleep latency test [MSLT], and the diagnosis) was expressed as new cases/100 000 persons/year.

RESULTS

There were 8 444 517 continuously enrolled patients and 6703 diagnosed with narcolepsy (prevalence overall: 79.4/100 000; without cataplexy: 65.4/100 000; with cataplexy: 14.0/100 000). On the basis of the three definitions of incidence, overall average annual incidence was 7.67, 7.13, and 4.87/100 000 persons/year. Incidence for narcolepsy without cataplexy was generally several times higher than narcolepsy with cataplexy. Prevalence and incidence were approximately 50% greater for females compared to males across most age groups. Prevalence was highest among the 21-30 years age group, with incidence highest among enrollees in their early 20s and late teens. Regionally, the North Central United States had the highest prevalence and incidence, whereas the West was the lowest.

CONCLUSION

We found greater prevalence and incidence of narcolepsy (including without cataplexy) than most previous studies. The increased proportions in females, enrollees in their early 20s, and US regional differences require further study. Increased awareness and early identification is critical in the management of this burdensome condition.

Narcolepsy Severity Scale: a reliable tool assessing symptom severity and consequences

Study Objectives

To define clinically relevant Narcolepsy Severity Scale (NSS) score ranges, confirm its main performances and sensitivity to medications, and determine whether items need to be weighted.

Methods

One hundred and forty-three consecutive untreated and 238 treated adults with narcolepsy type 1 (NT1) completed the NSS, a 15-item self-administered questionnaire (score: 0–57) that assesses the severity and consequences of the five major narcolepsy symptoms such as daytime sleepiness, cataplexy, hallucinations, sleep paralysis, and disturbed nighttime sleep (DNS). They also completed the Epworth Sleepiness scale (ESS; daytime sleepiness), Beck Depression Inventory (BDI; depressive symptoms), and EQ5D (quality of life).

Results

The mean symptom number (4.3 vs 3.5), NSS total score (33.3 ± 9.4 vs 24.3 ± 10.2), and number of narcolepsy symptoms (five symptoms: 53.1% vs 24.8%; four symptoms: 26.6% vs 22.7%; three symptoms: 15.4% vs 32.4%; two symptoms: 4.9% vs 20.2%) were significantly different between untreated and treated patients (p &lt; 0.0001). DNS was often the third symptom (95.5 per cent). The symptom number was associated with diagnosis delay, age at onset, and ESS and BDI scores. Comparisons with ESS, BDI and EQ5D showed that NSS item weighting was not necessary to highlight between-group differences. Four NSS severity levels were defined (mild, moderate, severe, and very severe) with between-group differences related to treatment. The probability of having ESS ≥ 16, BDI ≥ 20, and EQ-5D &lt; 60 increased with the severity level.

Conclusion

NSS is valid, reliable, and responsive to treatment in patients with NT1, with four clinically relevant severity score ranges provided. NSS has adequate clinimetric properties for broadening its use for both clinic and research.

A randomized study of solriamfetol for excessive sleepiness in narcolepsy

Objective

Solriamfetol (JZP‐110) is a selective dopamine and norepinephrine reuptake inhibitor with wake‐promoting effects. This phase 3 study (NCT02348593) evaluated the safety and efficacy of solriamfetol in narcolepsy.

Methods

Patients with narcolepsy with mean sleep latency <25 minutes on the Maintenance of Wakefulness Test (MWT), Epworth Sleepiness Scale (ESS) score ≥10, and usual nightly sleep ≥6 hours were randomized to solriamfetol 75, 150, or 300 mg, or placebo for 12 weeks. Coprimary endpoints were change from baseline to week 12 in MWT and ESS. Improvement on the Patient Global Impression of Change (PGI‐C) was the key secondary endpoint.

Results

Safety and modified intention‐to‐treat populations included 236 and 231 patients, respectively. Solriamfetol 300 and 150 mg were positive on both coprimary endpoints. Least squares mean (standard error [SE]) changes from baseline were 12.3 (SE = 1.4) and 9.8 (SE = 1.3) minutes for solriamfetol 300 and 150 mg on the MWT, respectively, versus 2.1 (SE = 1.3) minutes for placebo, and −6.4 (SE = 0.7) for 300 mg and −5.4 (SE = 0.7) for 150 mg on the ESS versus −1.6 (SE = 0.7) for placebo (all p < 0.0001). At week 12, higher percentages of patients treated with solriamfetol 150 mg (78.2%) and 300 mg (84.7%) reported PGI‐C improvement relative to placebo (39.7%; both p < 0.0001). Adverse events ≥5% across all solriamfetol doses included headache (21.5%), nausea (10.7%), decreased appetite (10.7%), nasopharyngitis (9.0%), dry mouth (7.3%), and anxiety (5.1%).

Interpretation

Solriamfetol has the potential to be an important therapeutic option for the treatment of impaired wakefulness and excessive sleepiness in patients with narcolepsy. ANN NEUROL 2019;85:359–370.

Narcolepsy in Children and Adults: A Guide to Improved Recognition, Diagnosis and Management

Narcolepsy is a rare condition that affects children and adults, and commonly has an onset in childhood. Time to appropriate diagnosis frequently is at least a decade. Unrecognized or misdiagnosed symptoms of narcolepsy contribute to increased morbidity, disability and socioeconomic liability in these patients. Delays in diagnosis may be related to variability in presentation in childhood, lack of familiarity with symptoms or appropriate diagnostic testing or misdiagnosis with accidental introduction of treatment that may modify or mask narcolepsy features. Improved awareness about the diagnosis and tailored therapies improve clinical and socioeconomic outcomes by reducing time to effective treatment. Application of effective treatment results in long-term benefits by improving clinical outcomes, potentially enabling improved education, increased employment opportunity, and improved work productivity and quality of life. This review provides a comprehensive stepwise approach to improve knowledge and comfort for recognition of symptoms, diagnostic strategies and management considerations of narcolepsy in children and adults.

Update on the pharmacologic management of narcolepsy: mechanisms of action and clinical implications

Narcolepsy is a chronic, debilitating neurological disorder of sleep-wake state instability. This instability underlies all narcolepsy symptoms, including excessive daytime sleepiness (EDS), symptoms of rapid eye movement (REM) sleep dysregulation (ie, cataplexy, hypnagogic/hypnopompic hallucinations, sleep paralysis), and disrupted nighttime sleep. Several neurotransmitter systems promote wakefulness, and various neural pathways are involved in regulating REM sleep-related muscle atonia, providing multiple targets for pharmacologic intervention to reduce EDS and cataplexy. Medications approved by the US Food and Drug Administration (FDA) for the treatment of EDS in narcolepsy include traditional stimulants (eg, amphetamines, methylphenidate), wake-promoting agents (eg, modafinil, armodafinil), and solriamfetol, which mainly act on dopaminergic and noradrenergic pathways. Sodium oxybate (thought to act via GABA_B receptors) is FDA-approved for the treatment of EDS and cataplexy. Pitolisant, a histamine 3 (H₃)-receptor antagonist/inverse agonist, is approved by the European Medicines Agency (EMA) for the treatment of narcolepsy with or without cataplexy in adults and by the FDA for the treatment of EDS in adults with narcolepsy. Pitolisant increases the synthesis and release of histamine in the brain and modulates the release of other neurotransmitters (eg, norepinephrine, dopamine). Antidepressants that inhibit reuptake of serotonin and/or norepinephrine are widely used off label to manage cataplexy. In many patients with narcolepsy, combination treatment with medications that act via different neural pathways is necessary for optimal symptom management. Mechanism of action, pharmacokinetics, and abuse potential are important considerations in treatment selection and subsequent medication adjustments to maximize efficacy and mitigate adverse effects in the treatment of patients with narcolepsy.

Gamma-hydroxybutyrate (GHB) for narcolepsy in adults: an updated systematic review and meta-analysis

BACKGROUND

Narcolepsy is a chronic and debilitating sleep disorder characterized by cataplexy and excessive daytime sleeping. Gamma-hydroxybutyrate (GHB) has been widely used to treat narcolepsy, and new findings have been published in recent years.

OBJECTIVE

A meta-analysis was conducted to assess the efficacy and tolerability of GHB treatment in adults with narcolepsy.

METHODS

A systematic search of PubMed, Cochrane, Embase, Web of Science, and clinical-trials.gov from inception to June 2018 was performed. Change in daily diaries and polysomnographic data of narcoleptic patients were defined as the efficacy outcomes. The tolerability and acceptability outcomes were the rates of adverse events and dropping out for adverse effects or other reasons.

RESULTS

Fifteen randomized controlled trials involving 2104 participants were identified. GHB was found to improve cataplexy attacks (P = 0.001), subjective daytime sleepiness (P < 0.0001), daytime sleep latency (P < 0.0001), inadvertent naps/sleep attacks (P < 0.00001), effective rates (Clinical Global Impression of change) (P < 0.00001), hypnagogic hallucinations (P = 0.004), sleep paralysis (P = 0.004), stage 1 sleep (P = 0.04), slow wave sleep (P = 0.003), REM sleep (P = 0.0006), sleep shifts (P = 0.005), nocturnal awakenings (P = 0.004), quality of nocturnal sleep (P < 0.00001), chin muscle activity, and quality of life, but had no effect on stage 2 sleep (P = 0.88). GHB was less well tolerated than placebo because of side effects that occurred in a dose-dependent fashion (RR = 6.08; 95% CI = 2.18 to 16.97; P = 0.0006).

CONCLUSIONS

GHB was effective in improving narcolepsy-cataplexy and related symptoms in adults but was less well tolerated than placebo because of dose-dependent side effects.

Discovery and Development of N-[4-(1-Cyclobutylpiperidin-4-yloxy)phenyl]-2-(morpholin-4-yl)acetamide Dihydrochloride (SUVN-G3031): A Novel, Potent, Selective, and Orally Active Histamine H3 Receptor Inverse Agonist with Robust Wake-Promoting Activity

A series of chemical optimizations guided by in vitro affinity at a histamine H₃ receptor (H₃R), physicochemical properties, and pharmacokinetics in rats resulted in identification of N-[4-(1-cyclobutyl-piperidin-4-yloxy)phenyl]-2-(morpholin-4-yl)acetamide dihydrochloride (17v, SUVN-G3031) as a clinical candidate. Compound 17v is a potent (hH₃R K_i = 8.73 nM) inverse agonist at H₃R with selectivity over other 70 targets, Compound 17v has adequate oral exposures and favorable elimination half-lives both in rats and dogs. It demonstrated high receptor occupancy and marked wake-promoting effects with decreased rapid-eye-movement sleep in orexin-B saporin lesioned rats supporting its potential therapeutic utility in treating human sleep disorders. It had no effect on the locomotor activity at doses several fold higher than its efficacious dose. It is devoid of hERG and phospholipidosis issues. Phase-1 evaluation for safety, tolerability, and pharmacokinetics, and long-term safety studies in animals have been successfully completed without any concern for further development.

A randomized, double-blind, placebo-controlled, crossover study to evaluate the human abuse liability of solriamfetol, a selective dopamine and norepinephrine reuptake inhibitor

BACKGROUND

This study evaluated the human abuse potential of solriamfetol (formerly JZP-110), a selective dopamine and norepinephrine reuptake inhibitor with robust wake-promoting effects.

METHODS

Adults with a recent history of recreational polydrug use, including stimulants, and who met criteria in a Qualification Phase were randomized to one of six sequences in a Test Phase. Each Test Phase sequence included a single administration of placebo, solriamfetol (300, 600, and 1200 mg), and phentermine (45 and 90 mg), with a two-day washout between periods. The primary endpoint was peak rating ( Emax) of Liking at the Moment across the first 12 h on a liking/disliking visual analog scale; key secondary endpoints were Next Day Overall Drug Liking, how much the participant would like to Take the Drug Again, and positive and negative subjective effects. Safety was also assessed throughout the study.

RESULTS

Of 43 participants (74.4% male; mean age 29.3 years), 37 completed the study. Peak Emax Liking at the Moment for all solriamfetol doses was significantly greater than placebo and significantly less than phentermine 90 mg ( p < 0.05). Overall Next Day Drug Liking was greater than placebo for solriamfetol 300 mg and phentermine 45 and 90 mg ( p < 0.05). Willingness to Take the Drug Again was significantly greater than placebo and significantly less than both doses of phentermine for all doses of solriamfetol ( p < 0.05). Ratings of negative subjective effects (bad effects, disliking, anxiety, agitation) were higher with solriamfetol 600 and 1200 mg relative to phentermine. The most common treatment-emergent adverse events with solriamfetol were hypervigilance, elevated mood, dry mouth, hyperhidrosis, and insomnia.

CONCLUSION

Solriamfetol appears to have abuse potential similar to or lower than phentermine.

Neurobiological and immunogenetic aspects of narcolepsy: Implications for pharmacotherapy

Excessive daytime sleepiness (EDS) and cataplexy are common symptoms of narcolepsy, a sleep disorder associated with the loss of hypocretin/orexin (Hcrt) neurons. Although only a few drugs have received regulatory approval for narcolepsy to date, treatment involves diverse medications that affect multiple biochemical targets and neural circuits. Clinical trials have demonstrated efficacy for the following classes of drugs as narcolepsy treatments: alerting medications (amphetamine, methylphenidate, modafinil/armodafinil, solriamfetol [JZP-110]), antidepressants (tricyclic antidepressants, selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors), sodium oxybate, and the H₃-receptor inverse agonist/antagonist pitolisant. Enhanced catecholamine availability and regulation of locus coeruleus (LC) norepinephrine (NE) neuron activity is likely central to the therapeutic activity of most of these compounds. LC NE neurons are integral to sleep/wake regulation and muscle tone; reduced excitatory input to the LC due to compromise of Hcrt/orexin neurons (likely due to autoimmune factors) results in LC NE dysregulation and contributes to narcolepsy/cataplexy symptoms. Agents that increase catecholamines and/or LC activity may mitigate EDS and cataplexy by elevating NE regulation of GABAergic inputs from the amygdala. Consequently, novel medications and treatment strategies aimed at preserving and/or modulating Hcrt/orexin-LC circuit integrity are warranted in narcolepsy/cataplexy.

A Sleep Medicine Curriculum for Pulmonary and Pulmonary/Critical Care Fellowship Programs: A Multisociety Expert Panel Report

BACKGROUND

Pulmonary medicine specialists find themselves responsible for the diagnosis and management of patients with sleep disorders. Despite the increasing prevalence of many of these conditions, many sleep medicine fellowship training slots go unfilled, leading to a growing gap between the volume of patients seeking care for sleep abnormalities and the number of physicians formally trained to manage them. To address this need, we convened a multisociety panel to develop a list of curricular recommendations related to sleep medicine for pulmonary fellowship training programs.

METHODS

Surveys of pulmonary and pulmonary/critical care fellowship program directors and recent graduates of these programs were performed to assess the current state of sleep medicine education in pulmonary training, as well as the current scope of practice of pulmonary specialists. These data were used to inform a modified Delphi process focused on developing curricular recommendations relevant to sleep medicine.

RESULTS

Surveys confirmed that pulmonary medicine specialists are often responsible for the diagnosis and treatment of a number of sleep conditions, including several that are not traditionally considered related to respiratory medicine. Through five rounds of voting, the panel crafted a list of 52 curricular competencies relevant to sleep medicine for recommended inclusion in pulmonary training programs.

CONCLUSIONS

Practicing pulmonary specialists require a broad knowledge of sleep medicine to provide appropriate care to patients they will be expected to manage. Training program directors may use the list of competencies as a framework to ensure adequate mastery of important content by graduating fellows.

Clinical Characteristics and Burden of Illness in Pediatric Patients with Narcolepsy

BACKGROUND

Narcolepsy is a chronic and lifelong neurologic disorder with onset commonly occurring in childhood or adolescence, and affecting approximately 0.025% to 0.05% of the general population. The primary symptom is excessive daytime sleepiness, which is accompanied by cataplexy in 70% of patients. Other common symptoms include sleep paralysis, hallucinations upon falling asleep or waking, and disrupted nocturnal sleep. Narcolepsy is associated with a considerable burden of illness (BOI), which has been well characterized in adults, and is exacerbated by delays in symptom recognition, diagnosis, and intervention.

METHODS

This review describes the specific characteristics and BOI of pediatric narcolepsy, using a wide range of published research data.

RESULTS

Pediatric narcolepsy presents distinct challenges in diagnosis and management. Narcolepsy symptoms often initially manifest differently in children and adolescents versus adults, which may pose diagnostic dilemmas. Children often respond to sleepiness with irritability, hyperactivity, and poor attention, which may be misinterpreted as misbehavior or neurocognitive sequelae of other conditions. Pediatric cataplexy symptoms may include subtle and unusual facial expressions or choreic-like movements, which are not observed in adults. Insufficient sleep and circadian rhythm disorders presenting with excessive daytime sleepiness are common in adolescents, potentially confounding narcolepsy diagnosis. Pediatric narcolepsy is also associated with comorbidities including rapid weight gain, precocious puberty, and attention deficit hyperactivity disorder, and increased risk for deficits in social functioning, depression, and anxiety. School performance is also typically impaired, requiring special education services.

CONCLUSIONS

Thus, the discrete BOI of pediatric narcolepsy underscores the need for prompt and accurate diagnosis, and appropriate treatment of this disorder.

Neurocognition, sleep, and PET findings in type 2 vs type 1 narcolepsy

OBJECTIVE

To analyze differences in functional brain images collected in patients with type 2 and type 1 narcolepsy compared to normal controls and the relationship among brain images, objective neuropsychologic tests, and sleep findings.

METHODS

Data collection included comprehensive clinical investigation, study of sleep/wake with actigraphy, polysomnography, Multiple Sleep Latency Test, human leukocyte antigen typing, ¹⁸F-fluorodeoxyglucose PET, and cognitive tests obtained from 29 patients with type 2 narcolepsy, 104 patients with type 1 narcolepsy, and 26 sex- and age-matched normal control individuals. Conners' Continuous Performance Test (CPT II) and Wisconsin Card-Sorting Task were performed simultaneously with the FDG-PET examination. After analyses of variance, data between patients with type 1 and type 2 narcolepsy were compared by post hoc analysis, and correlation between functional brain imaging findings and results of neurocognitive tests was obtained.

RESULTS

All patients with narcolepsy presented with at least 2 sleep-onset REM periods (SOREMP) and subjective sleepiness. Patients with type 2 narcolepsy compared to patients with type 1 narcolepsy had significantly less SOREMP, longer mean sleep latencies, and lower body mass indexes, apnea-hypopnea indexes, and frequency of human leukocyte antigen DQ-Beta1*0602. In patients with type 2 narcolepsy, FDG-PET studies showed significantly less hypermetabolism in the fusiform gyrus, striatum, hippocampus, thalamus, basal ganglia, and cerebellum than in patients with type 1 narcolepsy, and significantly less hypometabolism in the regions of frontal lobe, posterior cingulum, angular gyrus, and part of the parietal lobe; these changes were associated with fewer errors on the CPT.

CONCLUSION

Young patients with type 2 narcolepsy have fewer clinical impairments and less distinct brain functional abnormalities than patients with type 1 narcolepsy, who are significantly more affected.

Quality of life and trust among young people with narcolepsy and their families, after the Pandemrix® vaccination: protocol for a case-control study

Background

The extensive vaccination programme against swine flu resulted in an increased incidence of narcolepsy among children and adolescents. There is a need to explore if these young persons’ experiences have affected their trust in healthcare, their willingness to participate in future prevention programmes, and their contacts with the healthcare system. The overall aim is to identify factors important for the life-situation of children and adolescents with narcolepsy and their families, and factors that correlate with trust in healthcare.

Methods/design

Data will be collected via questionnaires from all available children with narcolepsy following the vaccination and their families, as well as a control group of children with diabetes and their families. Longitudinal descriptive interviews will also be conducted with a selection of 20–25 children and their families. Techniques from media research will be used for Internet-based data collection and analysis of information relating to narcolepsy from social media.

Discussion

This project will use the situation of young persons with narcolepsy after the swine flu vaccination as a case to build a model that can be used in situations where trust in healthcare is essential. This model will be based on findings from the included studies on how trust is influenced by support, quality of life, burden of disease, impact on family, and use of social media. The model developed in this project will be beneficial in future situations where trust in healthcare is essential, such as new pandemic outbreaks but also for “everyday” adherence to health advice.

Correlation of Changes in Patient-Reported Quality of Life With Physician-Rated Global Impression of Change in Patients With Narcolepsy Participating in a Clinical Trial of Sodium Oxybate: A Post Hoc Analysis

INTRODUCTION

Narcolepsy patients report lower health-related quality of life (HRQoL) than the general population, as measured by the Short Form-36 Health Survey (SF-36). This analysis evaluated whether changes in SF-36 correlated with physician-rated Clinical Global Impression of Change (CGI-C).

METHODS

Data were from 209 of 228 narcolepsy patients participating in an 8-week clinical trial of sodium oxybate. Changes from baseline for SF-36 subscales (Physical Functioning, Role Physical, Bodily Pain, General Health, Vitality, Social Functioning, Role Emotional, and Mental Health) and the summary scores were evaluated for correlation with CGI-C overall and by treatment group. Correlations were calculated using the Pearson product-moment correlation coefficient (r).

RESULTS

Correlations described an inverse relationship in scores, but a direct relationship in improvement; lower CGI-C scores (i.e., better) were associated with higher SF-36 subscale scores (i.e., improved HRQoL). Moderate and significant correlations were observed for Vitality (r = -0.464; P < 0.0001) and Role Physical (r = -0.310; P < 0.0001) subscales, but weak correlations were observed with other subscales including summary scores. Correlations were stronger at higher sodium oxybate doses for most SF-36 subscales.

CONCLUSION

Some aspects of HRQoL, measured by the SF-36, may be associated with narcolepsy. In particular, Vitality (indicative of energy and tiredness) and Role Physical (impact of physical function on daily roles) moderately correlated with overall change in status observed by clinicians. However, lack of strong correlations between SF-36 and CGI-C indicates differences in patient and clinician perspectives of disease, and suggest a need for broader assessment of the impact of narcolepsy and its treatment on patients.

FUNDING

Jazz Pharmaceuticals.