Explore the vast range of titles available.

Narcolepsy type 1 is caused by severe loss or lack of brain orexin neuropeptides. We conducted a phase 2, randomized, placebo-controlled trial of TAK-994, an oral orexin receptor 2-selective agonist, in patients with narcolepsy type 1. Patients with confirmed narcolepsy type 1 according to clinical criteria were randomly assigned to receive twice-daily oral TAK-994 (30 mg, 90 mg, or 180 mg) or placebo. The primary end point was the mean change from baseline to week 8 in average sleep latency (the time it takes to fall asleep) on the Maintenance of Wakefulness Test (range, 0 to 40 minutes; normal ability to stay awake, ≥20 minutes). Secondary end points included the change in the Epworth Sleepiness Scale (ESS) score (range, 0 to 24, with higher scores indicating greater daytime sleepiness; normal, <10) and the weekly cataplexy rate. Of the 73 patients, 17 received TAK-994 at a dose of 30 mg twice daily, 20 received 90 mg twice daily, 19 received 180 mg twice daily, and 17 received placebo. The phase 2 trial and an extension trial were terminated early owing to hepatic adverse events. Primary end-point data were available for 41 patients (56%); the main reason for missing data was early trial termination. Least-squares mean changes to week 8 in average sleep latency on the MWT were 23.9 minutes in the 30-mg group, 27.4 minutes in the 90-mg group, 32.6 minutes in the 180-mg group, and -2.5 minutes in the placebo group (difference vs. placebo, 26.4 minutes in the 30-mg group, 29.9 minutes in the 90-mg group, and 35.0 minutes the 180-mg group; P<0.001 for all comparisons). Least-squares mean changes to week 8 in the ESS score were -12.2 in the 30-mg group, -13.5 in the 90-mg group, -15.1 in the 180-mg group, and -2.1 in the placebo group (difference vs. placebo, -10.1 in the 30-mg group, -11.4 in the 90-mg group, and -13.0 in the 180-mg group). Weekly incidences of cataplexy at week 8 were 0.27 in the 30-mg group, 1.14 in the 90-mg group, 0.88 in the 180-mg group, and 5.83 in the placebo group (rate ratio vs. placebo, 0.05 in the 30-mg group, 0.20 in the 90-mg group, and 0.15 in the 180-mg group). A total of 44 of 56 patients (79%) receiving TAK-994 had adverse events, most commonly urinary urgency or frequency. Clinically important elevations in liver-enzyme levels occurred in 5 patients, and drug-induced liver injury meeting Hy's law criteria occurred in 3 patients. In a phase 2 trial involving patients with narcolepsy type 1, an orexin receptor 2 agonist resulted in greater improvements on measures of sleepiness and cataplexy than placebo over a period of 8 weeks but was associated with hepatotoxic effects. (Funded by Takeda Development Center Americas; TAK-994-1501 and TAK-994-1504 ClinicalTrials.gov numbers, NCT04096560 and NCT04820842.).

In this phase 2 randomized, placebo-controlled trial involving 112 participants with narcolepsy type 1, oveporexton significantly improved measures of wakefulness, sleepiness, and cataplexy over a period of 8 weeks.

Histaminergic neurons are crucial to maintain wakefulness, but their role in cataplexy is unknown. We assessed the safety and efficacy of pitolisant, a histamine H3 receptor inverse agonist, for treatment of cataplexy in patients with narcolepsy. For this randomised, double-blind, placebo-controlled trial we recruited patients with narcolepsy from 16 sleep centres in nine countries (Bulgaria, Czech Republic, Hungary, Macedonia, Poland, Russia, Serbia, Turkey, and Ukraine). Patients were eligible if they were aged 18 years or older, diagnosed with narcolepsy with cataplexy according to version two of the International Classification of Sleep Disorders criteria, experienced at least three cataplexies per week, and had excessive daytime sleepiness (defined as an Epworth Sleepiness Scale score ≥12). We used a computer-generated sequence via an interactive web response system to randomly assign patients to receive either pitolisant or placebo once per day (1:1 ratio). Randomisation was done in blocks of four. Participants and investigators were masked to treatment allocation. Treatment lasted for 7 weeks: 3 weeks of flexible dosing decided by investigators according to efficacy and tolerance (5 mg, 10 mg, or 20 mg oral pitolisant), followed by 4 weeks of stable dosing (5 mg, 10 mg, 20 mg, or 40 mg). The primary endpoint was the change in the average number of cataplexy attacks per week as recorded in patient diaries (weekly cataplexy rate [WCR]) between the 2 weeks of baseline and the 4 weeks of stable dosing period. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01800045. The trial was done between April 19, 2013, and Jan 28, 2015. We screened 117 patients, 106 of whom were randomly assigned to treatment (54 to pitolisant and 52 to placebo) and, after dropout, 54 patients from the pitolisant group and 51 from the placebo group were included in the intention-to-treat analysis. The WCR during the stable dosing period compared with baseline was decreased by 75% (WCRfinal=2·27; WCRbaseline=9·15; WCRfinal/baseline=0·25) in patients who received pitolisant and 38% (WCRfinal=4·52; WCRbaseline=7·31; WCRfinal/baseline=0·62) in patients who received placebo (rate ratio 0·512; 95% CI 0·43–0·60, p<0·0001). Treatment-related adverse events were significantly more common in the pitolisant group than in the placebo group (15 [28%] of 54 vs 6 [12%] of 51; p=0·048). There were no serious adverse events, but one case of severe nausea in the pitolisant group. The most frequent adverse events in the pitolisant group (headache, irritability, anxiety, and nausea) were mild or moderate except one case of severe nausea. No withdrawal syndrome was detected following pitolisant treatment; one case was detected in the placebo group. Pitolisant was well tolerated and efficacious in reducing cataplexy. If confirmed in long-term studies, pitolisant might constitute a useful first-line therapy for cataplexy in patients with narcolepsy, for whom there are currently few therapeutic options. Bioprojet, France.

Abstract 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 (Emax) 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 Emax 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 Emax was similar for pitolisant (both doses) and placebo. Similarly, for key secondary measures of Overall Drug Liking and willingness to Take Drug Again, mean Emax 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.

Key Points Cataplexy is the pathognomonic symptom of narcolepsy, and is characterized by sudden involuntary loss of skeletal muscle tone during wakefulness, typically triggered by strong positive emotions The pathogenesis of cataplexy in human narcolepsy involves degeneration of orexin neurons in the hypothalamus; genetically induced orexin deficiency causes cataplexy in both mice and dogs Cataplexy is thought to result from activation during wakefulness of the sleep circuitry involved in rapid eye movement sleep Reduced noradrenergic and increased inhibitory input to motor neurons causes muscle weakness or paralysis during cataplexy; positive emotions trigger cataplexy through neuronal pathways in the amygdala and medial prefrontal cortex γ-Hydroxybutyrate (GHB) and antidepressants are effective treatments for cataplexy, but most treatments (excluding GHB) are used 'off-label' Novel and experimental treatments to manage cataplexy are required, including orexin replacement therapy and immune-based therapies Cataplexy is the pathognomonic symptom of narcolepsy, a condition that is caused by depletion of orexin neurons. Cataplectic attacks are characterized by sudden involuntary muscle weakness or paralysis, often triggered by strong emotions. In this article, Dauvilliers et al . review the latest understanding of potential mechanisms underlying narcolepsy and cataplexy, the utility of experimental models, and the need for early diagnosis and therapy. Cataplexy is the pathognomonic symptom of narcolepsy, and is the sudden uncontrollable onset of skeletal muscle paralysis or weakness during wakefulness. Cataplexy is incapacitating because it leaves the individual awake but temporarily either fully or partially paralyzed. Occurring spontaneously, cataplexy is typically triggered by strong positive emotions such as laughter and is often underdiagnosed owing to a variable disease course in terms of age of onset, presenting symptoms, triggers, frequency and intensity of attacks. This disorder occurs almost exclusively in patients with depletion of hypothalamic orexin neurons. One pathogenetic mechanism that has been hypothesized for cataplexy is the activation, during wakefulness, of brainstem circuitry that normally induces muscle tone suppression in rapid eye movement sleep. Muscle weakness during cataplexy is caused by decreased excitation of noradrenergic neurons and increased inhibition of skeletal motor neurons by γ-aminobutyric acid-releasing or glycinergic neurons. The amygdala and medial prefrontal cortex contain neural pathways through which positive emotions probably trigger cataplectic attacks. Despite major advances in understanding disease mechanisms in cataplexy, therapeutic management is largely symptomatic, with antidepressants and γ-hydroxybutyrate being the most effective treatments. This Review describes the clinical and pathophysiological aspects of cataplexy, and outlines optimal therapeutic management strategies.

Narcolepsy type 1 (NT1) is a sleep disorder caused by a loss of orexinergic neurons. Narcolepsy type 2 (NT2) is heterogeneous; affected individuals typically have normal orexin levels. Following evaluation in mice, the effects of the orexin 2 receptor (OX2R)-selective agonist danavorexton were evaluated in single- and multiple-rising-dose studies in healthy adults, and in individuals with NT1 and NT2. In orexin/ataxin-3 narcolepsy mice, danavorexton reduced sleep/wakefulness fragmentation and cataplexy-like episodes during the active phase. In humans, danavorexton administered intravenously was well tolerated and was associated with marked improvements in sleep latency in both NT1 and NT2. In individuals with NT1, danavorexton dose-dependently increased sleep latency in the Maintenance of Wakefulness Test, up to the ceiling effect of 40 min, in both the single- and multiple-rising-dose studies. These findings indicate that OX2Rs remain functional despite long-term orexin loss in NT1. OX2R-selective agonists are a promising treatment for both NT1 and NT2.

The discovery of hypocretins (orexins) and their causal implication in narcolepsy is the most important advance in sleep research and sleep medicine since the discovery of rapid eye movement sleep. Narcolepsy with cataplexy is caused by hypocretin deficiency owing to destruction of most of the hypocretin-producing neurons in the hypothalamus. Ablation of hypocretin or hypocretin receptors also leads to narcolepsy phenotypes in animal models. Although the exact mechanism of hypocretin deficiency is unknown, evidence from the past 20 years strongly favours an immune-mediated or autoimmune attack, targeting specifically hypocretin neurons in genetically predisposed individuals. These neurons form an extensive network of projections throughout the brain and show activity linked to motivational behaviours. The hypothesis that a targeted immune-mediated or autoimmune attack causes the specific degeneration of hypocretin neurons arose mainly through the discovery of genetic associations, first with the HLA-DQB1*06:02 allele and then with the T-cell receptor α locus. Guided by these genetic findings and now awaiting experimental testing are models of the possible immune mechanisms by which a specific and localised brain cell population could become targeted by T-cell subsets. Great hopes for the identification of new targets for therapeutic intervention in narcolepsy also reside in the development of patient-derived induced pluripotent stem cell systems.

Narcolepsy is a life-long disorder characterised by excessive daytime sleepiness and cataplexy, often arising in childhood or adolescence. Pitolisant, a selective histamine H3 receptor inverse agonist, has been approved in Europe and USA for adults with narcolepsy with or without cataplexy, with a favourable safety profile. This phase 3 study aimed to assess the safety and efficacy of pitolisant in children with narcolepsy with or without cataplexy. For this double-blind, randomised, placebo-controlled, multisite study, we recruited patients aged 6–17 years with narcolepsy with or without cataplexy in 11 sleep centres in five countries (Italy, France, Netherlands, Russia, and Finland). Participants were required to have a Pediatric Daytime Sleepiness Scale score of 15 or greater and to have not received psychostimulants for at least 14 days before enrolment; participants who needed anticataplectics (including sodium oxybate) were required to have been on a stable dose for at least 1 month. Participants were randomly assigned to treatment with pitolisant or placebo in a 2:1 ratio at the end of screening. Randomisation was stratified by study centre and treatment was allocated using an interactive web response system. After a 4-week screening period including a 2-week baseline period, patients entered in a 4-week individual up-titration scheme from 5 mg a day to a maximum of 40 mg a day of pitolisant or placebo; treatment was administered at a stable dose for 4 weeks, followed by a 1-week placebo period. For the primary analysis, we assessed pitolisant versus placebo using change in the Ullanlinna Narcolepsy Scale (UNS) total score from baseline to the end of double-blind period in the full analysis set, defined as all randomly allocated patients who received at least one dose of treatment and who had at least one baseline UNS value. A decrease in the UNS total score reflects a reduction in both excessive daytime sleepiness and cataplexy. All adverse events were assessed in the safety population, defined as all participants who took at least one dose of study medication. An open-label follow-up is ongoing. This study is registered at ClinicalTrials.gov, NCT02611687. Between June 6, 2016, and April 3, 2021, we screened 115 participants and 110 were randomly assigned (mean age 12·9 [SD 3·0] years, 61 [55%] male, and 90 [82%] with cataplexy; 72 assigned to pitolisant and 38 to placebo); 107 (70 receiving pitolisant and 37 receiving placebo) completed the double-blind period. The mean adjusted difference in UNS total score from baseline to the end of the double-blind period was –6·3 (SE 1·1) in the pitolisant group and –2·6 (1·4) in the placebo group (least squares mean difference –3·7; 95% CI –6·4 to –1·0, p=0·007). Treatment-emergent adverse events were reported in 22 (31%) of 72 patients in the pitolisant group and 13 (34%) of 38 patients in the placebo group. The most frequently reported adverse events (affecting ≥5% of patients) in either group were headache (14 [19%] in the pitolisant group and three [8%] in the placebo group) and insomnia (five [7%] in the pitolisant group and one [3%] in the placebo group). Pitolisant treatment resulted in an improvement in narcolepsy symptoms in children, although the UNS was not validated for use in children with narcolepsy when our study began. The safety profile was similar to that reported in adults but further studies are needed to confirm long-term safety. Bioprojet.

Abstract Study Objectives Evaluate efficacy and safety of lower-sodium oxybate (LXB), a novel oxybate medication with 92% less sodium than sodium oxybate (SXB). Methods Adults aged 18–70 years with narcolepsy with cataplexy were eligible. The study included a ≤30-day screening period; a 12-week, open-label, optimized treatment and titration period to transition to LXB from previous medications for the treatment of cataplexy; a 2-week stable-dose period (SDP); a 2-week, double-blind, randomized withdrawal period (DBRWP); and a 2-week safety follow-up. During DBRWP, participants were randomized 1:1 to placebo or to continue LXB treatment. Results Efficacy was assessed in 134 participants who received randomized treatment, and safety was assessed in all enrolled participants (N = 201). Statistically significant worsening of symptoms was observed in participants randomized to placebo, with median (first quartile [Q1], third quartile [Q3]) change in weekly number of cataplexy attacks from SDP to DBRWP (primary efficacy endpoint) in the placebo group of 2.35 (0.00, 11.61) versus 0.00 (−0.49, 1.75) in the LXB group (p < 0.0001; mean [standard deviation, SD] change: 11.46 [24.751] vs 0.12 [5.772]), and median (Q1, Q3) change in Epworth Sleepiness Scale score (key secondary efficacy endpoint) of 2.0 (0.0, 5.0) in the placebo group versus 0.0 (−1.0, 1.0) in the LXB group (p < 0.0001; mean [SD] change: 3.0 [4.68] vs 0.0 [2.90]). The most common treatment-emergent adverse events with LXB were headache (20.4%), nausea (12.9%), and dizziness (10.4%). Conclusions Efficacy of LXB for the treatment of cataplexy and excessive daytime sleepiness was demonstrated. The safety profile of LXB was consistent with SXB. Clinical trial registration NCT03030599.

Abstract Study Objectives To assess the efficacy and safety of FT218, a novel once-nightly formulation of sodium oxybate (ON-SXB), in patients with narcolepsy in the phase 3 REST-ON trial. Methods Narcolepsy patients aged ≥16 years were randomized 1:1 to uptitration of ON-SXB (4.5, 6, 7.5, and 9 g) or placebo. Three coprimary endpoints were change from baseline in mean sleep latency on the Maintenance of Wakefulness Test, Clinical Global Impression-Improvement rating, and weekly cataplexy attacks at 9, 7.5, and 6 g. Secondary endpoints included change from baseline on the Epworth Sleepiness Scale. Safety included adverse drug reactions and clinical laboratory assessments. Results In total, 222 patients were randomized; 212 received ≥1 dose of ON-SXB (n = 107) or placebo (n = 105). For the three coprimary endpoints and Epworth Sleepiness Scale, all three doses of ON-SXB demonstrated clinically meaningful, statistically significant improvement versus placebo (all p < 0.001). For ON-SXB 9 g versus placebo, increase in mean sleep latency was 10.8 versus 4.7 min (Least squares mean difference, LSMD [95% CI], 6.13 [3.52 to 8.75]), 72.0% versus 31.6% were rated much/very much improved on Clinical Global Impression-Improvement (OR [95% CI], 5.56 [2.76 to 11.23]), change in mean weekly number of cataplexy attacks was –11.5 versus –4.9 (LSMD [95% CI], –6.65 [–9.32 to –3.98]), and change in Epworth Sleepiness Scale was –6.5 and –2.7 (LSMD [95% CI], –6.52 [–5.47 to –2.26]). Common adverse reactions included nausea, vomiting, headache, dizziness, and enuresis. Conclusions ON-SXB significantly improved narcolepsy symptoms; its safety profile was consistent with SXB. ON-SXB conferred efficacy with a clearly beneficial single nighttime dose. Clinical Trial Registration ClinicalTrials.gov: NCT02720744, https://clinicaltrials.gov/ct2/show/NCT02720744.