Effect of sodium oxybate on body mass index in pediatric patients with narcolepsy.

STUDY OBJECTIVES: We examined body mass index (BMI) changes associated with sodium oxybate treatment (SXB) in pediatric patients with narcolepsy with cataplexy who participated in a double-blind, placebo-controlled, randomized withdrawal study and an open-label continuation period. METHODS: Participants were aged 7-16 years at screening. SXB-naive participants titrated to twice-nightly dosing of SXB then entered a 2-week stable-dose period; participants taking SXB at study entry entered a 3-week stable-dose period. After a 2-week randomized withdrawal period, all participants entered an open-label safety period (OLP; main study duration: ≤ 52 weeks). Participants who completed the OLP were allowed to enter the open-label continuation period (an additional 1-2 years). BMI percentile categories were defined as underweight (< 5th), normal (5th to < 85th), overweight (≥ 85th to < 95th), and obese (≥ 95th). RESULTS: Median BMI percentile decreased from baseline to OLP week 52 in SXB-naive participants who were normal weight at baseline (decreased from 77.0 to 35.0) or overweight/obese at baseline (98.0 to 86.7). Median BMI percentile decreased to a lesser extent in participants taking twice-nightly SXB at study entry who were normal weight at baseline (54.6 to 53.0) or overweight/obese at baseline (96.5 to 88.9). Shifts in BMI category from baseline to week 52 were sometimes noted. In SXB-naive participants, 9/10 (90.0%) who were overweight became normal weight, 7/25 (28.0%) who were obese became normal weight, 3/25 (12.0%) who were obese became overweight, and 1/16 (6.3%) who was normal weight became obese. In participants taking SXB at baseline, 5/8 (62.5%) who were overweight became normal weight, 3/6 (50.0%) who were obese became overweight, 1/14 (7.1%) who was normal weight became overweight, and 2/14 (14.3%) who were normal weight became underweight. Median BMI percentiles at months 6 and 12 of the open-label continuation period were similar to those at OLP end (OLP week 52). In SXB-naive participants, the evident BMI z-score decrease over time was relative to the screening values. CONCLUSIONS: Decreases in BMI percentile and z-score, and downward shifts in BMI category, were observed within 1 year of SXB treatment in pediatric participants with narcolepsy with cataplexy. BMI decreases plateaued after approximately 1 year. 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/study/NCT02221869; Identifier: NCT02221869. CITATION: Dauvilliers Y, Lammers GJ, Lecendreux M, et al. Effect of sodium oxybate on body mass index in pediatric patients with narcolepsy. J Clin Sleep Med. 2024;20(3):445-454.

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.

Validation of the Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD) questionnaire in pediatric patients with narcolepsy with cataplexy aged 7-16 years.

OBJECTIVE/BACKGROUND: The Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD) measures daytime sleepiness, but had not previously been validated in children <12 years of age. PATIENTS/METHODS: Data from a sodium oxybate (SXB) study in pediatric participants with narcolepsy with cataplexy (ClinicalTrials.gov, NCT02221869) were used in this validation study. SXB-naive participants completed an open-label titration period prior to entering a 2-week stable-dose period; participants taking SXB at study entry entered a 3-week stable-dose period. RESULTS: The analysis population (N = 100) had a mean (SD) age of 11.9 (2.39) years. Internal consistency as assessed by Cronbach's alpha was 0.750 (95% CI, 0.681-0.819). The intraclass correlation coefficient for the test-retest reliability assessment (n = 64 with stable or no stimulant use at study entry) was 0.755 (95% CI, 0.626-0.844). Responsiveness to change, measured as the mean within-person change in 1-week ESS-CHAD score over time in SXB-naive participants (n = 59) from baseline (before taking SXB) to end of the stable-dose period (taking the titrated amount of SXB), was -6.31 (95% CI: -7.61, -5.00; nominal P < 0.0001). For convergent construct validity, the mean (SD) scores for female (n = 40) and male (n = 60) participants were 13.98 (4.440) and 14.65 (4.050), respectively (nominal P = 0.4430). For divergent construct validity, the mean (SD) scores were 16.31 (2.978) in the group who were taking neither SXB nor stimulants at study entry (n = 32) and 13.47 (4.400) in the group taking SXB with or without stimulants at study entry (n = 68; nominal P = 0.0003). CONCLUSIONS: This evidence supports the validity of the 1-week ESS-CHAD in a pediatric population with narcolepsy.

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.

Assessing narcolepsy with cataplexy in children and adolescents: development of a cataplexy diary and the ESS-CHAD.

OBJECTIVE: The aim of this study was to qualitatively evaluate concepts for incorporation into a daily diary to capture cataplexy frequency and to assess the content validity of the Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD) in pediatric patients with narcolepsy. PATIENTS AND METHODS: Face-to-face concept elicitation and cognitive interviews were conducted with children (7-9 years; n=13) and adolescents (10-17 years; n=16) who have narcolepsy with cataplexy, and their parents/caregivers. RESULTS: Similarities and differences were noted between narcolepsy concepts described by children and their parents/caregivers, suggesting some different but complementary perspectives; parents may not recognize cataplexy symptoms/triggers as well as children, but parents have greater recognition of the circumstances of falling asleep. Cataplexy diary modifications included changes in definitions and examples of cataplexy, using child-friendly terminology, adding a quantitative question to determine daily frequency, and standardizing the questionnaire for evening administration with self-completion by the child. Modifications were made to ESS-CHAD for child-friendly wording and to ensure that items reflect activities (eating, watching TV/video) and environments (school, bus/car transport) in which children are likely to participate. Two ESS-CHAD versions were proposed: one with a 1-month recall period, for general use, and the other with a recall period of "since your last study visit," for research, which could be shorter or longer than 1 month (as short as 1 week). CONCLUSION: The cataplexy diary and ESS-CHAD were modified for the assessment of children and adolescents. Further psychometric validation is recommended. These measures are being used in a Phase III, placebo-controlled clinical trial of sodium oxybate in children and adolescents with narcolepsy.

Assessing sleepiness and cataplexy in children and adolescents with narcolepsy: a review of current patient-reported measures.

OBJECTIVE: The objective of this study was to review patient-reported outcome measures assessing excessive daytime sleepiness (EDS) or cataplexy in children or adolescents to determine their usefulness and limitations in pediatric narcolepsy assessment. METHODS: Searches were performed in Embase and Medline for pediatric measures of EDS and cataplexy that are either patient- or proxy-reported, and searches of http://www.clinicaltrials.gov/ were conducted for studies in narcolepsy that included at least one patient-reported measure. Further review was performed if sleepiness questionnaires (child or proxy-reported), sleep questionnaires that may contain sleepiness questions, proxy-reported child behavior questionnaires, or information on cataplexy measures were mentioned. RESULTS: All self-reported cataplexy questionnaires from among 27 citations were study-specific diaries and were not identifiable as a recognized validated questionnaire. For EDS, 118 of 401 abstracts were further reviewed and the names of 21 questionnaires identified, of which eight questionnaires did not return additional citations of their validation. The Epworth Sleepiness Scale (ESS) or a modified version was the most frequently used measure of EDS. Although all measures were associated with limitations for use in the pediatric population, the ESS has been successfully used in adolescents and was deemed readily amenable to further modification for children. CONCLUSIONS: There remains a dearth of validated measures for assessing EDS and cataplexy in children and adolescents with narcolepsy. The need for these measures may be filled by modification or adaptation of existing adult measures; a daily cataplexy diary and the ESS may be readily modified to make them child-friendly with regard to wording and settings, but should still undergo psychometric validation.

Sodium oxybate therapy provides multidimensional improvement in fibromyalgia: results of an international phase 3 trial.

BACKGROUND: Fibromyalgia is characterised by chronic musculoskeletal pain and multiple symptoms including fatigue, multidimensional function impairment, sleep disturbance and tenderness. Along with pain and fatigue, non-restorative sleep is a core symptom of fibromyalgia. Sodium oxybate (SXB) is thought to reduce non-restorative sleep abnormalities. This study evaluated effects of SXB on fibromyalgia-related pain and other symptoms. METHODS: 573 patients with fibromyalgia according to 1990 American College of Rheumatology criteria were enrolled at 108 centres in eight countries. Subjects were randomly assigned to placebo, SXB 4.5 g/night or SXB 6 g/night. The primary efficacy endpoint was the proportion of subjects with ≥30% reduction in pain visual analogue scale from baseline to treatment end. Other efficacy assessments included function, sleep quality, effect of sleep on function, fatigue, tenderness, health-related quality of life and subject's impression of change in overall wellbeing. RESULTS: Significant improvements in pain, sleep and other symptoms associated with fibromyalgia were seen in SXB treated subjects compared with placebo. The proportion of subjects with ≥30% pain reduction was 42.0% for SXB4.5 g/night (p=0.002) and 51.4% for SXB6 g/night (p<0.001) versus 26.8% for placebo. Quality of sleep (Jenkins sleep scale) improved by 20% for SXB4.5 g/night (p≤0.001) and 25% for SXB6 g/night (p≤0.001) versus 0.5% for placebo. Adverse events with an incidence ≥5% and twice placebo were nausea, dizziness, vomiting, insomnia, anxiety, somnolence, fatigue, muscle spasms and peripheral oedema. CONCLUSION: These results, combined with findings from previous phase 2 and 3 studies, provide supportive evidence that SXB therapy affords important benefits across multiple symptoms in subjects with fibromyalgia.

Safety overview of postmarketing and clinical experience of sodium oxybate (Xyrem): abuse, misuse, dependence, and diversion.

STUDY OBJECTIVES: This study reviewed the cumulative postmarketing and clinical safety experience with sodium oxybate (Xyrem), a treatment approved for cataplexy and excessive daytime sleepiness in narcolepsy. Study objectives were to investigate the occurrence of abuse/misuse of sodium oxybate since first market introduction in 2002, classify cases using DSM-IV criteria for substance abuse and dependence, and describe specific characteristics of these cases. METHODS: We retrospectively reviewed postmarketing spontaneous adverse event (AE) reports from 15 countries for all cases containing reporting terminology related to abuse/misuse to determine its occurrence. All death cases independent of causality were reviewed to identify associated risk factors. RESULTS: Approximately 26,000 patients worldwide received sodium oxybate from first market introduction in 2002 through March 2008. Of those 26,000 patients, 0.2% reported > or = 1 of the events studied. These included 10 cases (0.039%) meeting DSM-IV abuse criteria, 4 cases (0.016%) meeting DSM-IV dependence criteria, 8 cases (0.031%, including 3 of the previous 4) with withdrawal symptoms reported after discontinuation of sodium oxybate, 2 confirmed cases (0.008%) of sodium oxybate-facilitated sexual assault, 8 cases (0.031%) of overdose with suicidal intent, 21 deaths (0.08%) in patients receiving sodium oxybate treatment with 1 death known to be related to sodium oxybate, and 3 cases (0.01%) of traffic accidents involving drivers taking sodium oxybate. During this period, approximately 600,000 bottles of sodium oxybate were distributed, and 5 incidents (0.0009%) of diversion were reported. CONCLUSION: Cumulative postmarketing and clinical experience indicates a very low risk of abuse/misuse of sodium oxybate.