Melatonin: From Pharmacokinetics to Clinical Use in Autism Spectrum Disorder.

The role of melatonin has been extensively investigated in pathophysiological conditions, including autism spectrum disorder (ASD). Reduced melatonin secretion has been reported in ASD and led to many clinical trials using immediate-release and prolonged-release oral formulations of melatonin. However, melatonin's effects in ASD and the choice of formulation type require further study. Therapeutic benefits of melatonin on sleep disorders in ASD were observed, notably on sleep latency and sleep quality. Importantly, melatonin may also have a role in improving autistic behavioral impairments. The objective of this article is to review factors influencing treatment response and possible side effects following melatonin administration. It appears that the effects of exposure to exogenous melatonin are dependent on age, sex, route and time of administration, formulation type, dose, and association with several substances (such as tobacco or contraceptive pills). In addition, no major melatonin-related adverse effect was described in typical development and ASD. In conclusion, melatonin represents currently a well-validated and tolerated treatment for sleep disorders in children and adolescents with ASD. A more thorough consideration of factors influencing melatonin pharmacokinetics could illuminate the best use of melatonin in this population. Future studies are required in ASD to explore further dose-effect relationships of melatonin on sleep problems and autistic behavioral impairments.

Sleep, Growth, and Puberty After 2 Years of Prolonged-Release Melatonin in Children With Autism Spectrum Disorder.

OBJECTIVE: A recent 3-month double-blind, placebo-controlled study demonstrated efficacy and safety of pediatric prolonged-release melatonin (PedPRM) for insomnia in children with autism spectrum disorder. This study examined the long-term effects of PedPRM treatment on sleep, growth, body mass index, and pubertal development. METHOD: Eighty children and adolescents (2-17.5 years of age; 96% with autism spectrum disorder) who completed the double-blind, placebo-controlled trial were given 2 mg, 5 mg, or 10 mg PedPRM nightly up to 104 weeks, followed by a 2-week placebo period to assess withdrawal effects. RESULTS: Improvements in child sleep disturbance and caregiver satisfaction with child sleep patterns, quality of sleep, and quality of life were maintained throughout the 104-week treatment period (p < .001 versus baseline for all). During the 2-week withdrawal placebo period, measures declined compared with the treatment period but were still improved compared with baseline. PedPRM was generally safe; the most frequent treatment-related adverse events were fatigue (6.3%), somnolence (6.3%), and mood swings (4.2%). Changes in mean weight, height, body mass index, and pubertal status (Tanner staging done by a physician) were within normal ranges for age with no evidence of delay in body mass index or pubertal development. CONCLUSION: Nightly PedPRM at optimal dose (2, 5, or 10 mg nightly) is safe and effective for long-term treatment in children and adolescents with autism spectrum disorder and insomnia. There were no observed detrimental effects on children's growth and pubertal development and no withdrawal or safety issues related to the use or discontinuation of the drug. CLINICAL TRIAL REGISTRATION INFORMATION: Efficacy and Safety of Circadin in the Treatment of Sleep Disturbances in Children With Neurodevelopment Disabilities; https://clinicaltrials.gov/; NCT01906866.

Pediatric Prolonged-Release Melatonin for Sleep in Children with Autism Spectrum Disorder: Impact on Child Behavior and Caregiver's Quality of Life.

A randomized, 13-weeks, placebo-controlled double-blind study in 125 subjects aged 2-17.5 years with Autism Spectrum Disorder or Smith-Magenis syndrome and insomnia demonstrated efficacy and safety of easily-swallowed prolonged-release melatonin mini-tablets (PedPRM; 2-5 mg) in improving sleep duration and onset. Treatment effects on child behavior and caregiver's quality of life were evaluated. PedPRM treatment resulted in significant improvement in externalizing but not internalizing behavior (Strengths and Difficulties questionnaire; SDQ) compared to placebo (p = 0.021) with clinically-relevant improvements in 53.7% of PedPRM-treated versus 27.6% of placebo-treated subjects (p = 0.008). Caregivers' quality of life also improved with PedPRM versus placebo (p = 0.010) and correlated with the change in total SDQ (p = 0.0005). PedPRM alleviates insomnia-related difficulties, particularly externalizing behavior in the children, subsequently improving caregivers' quality of life.

Long-Term Efficacy and Safety of Pediatric Prolonged-Release Melatonin for Insomnia in Children with Autism Spectrum Disorder.

Objective: A recent double-blind randomized placebo-controlled study demonstrated 3-month efficacy and safety of a novel pediatric-appropriate prolonged-release melatonin (PedPRM) for insomnia in children and adolescents with autism spectrum disorder (ASD) and neurogenetic disorders (NGD) with/without attention-deficit/hyperactivity disorder comorbidity. Long-term efficacy and safety of PedPRM treatment was studied. Methods: A prospective, open-label efficacy and safety follow-up of nightly 2, 5, or 10 mg PedPRM in subjects who completed the 13-week double-blind trial (51 PedPRM; 44 placebo). Measures included caregiver-reported Sleep and Nap Diary, Composite Sleep Disturbance Index (CSDI), caregiver's Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale, and quality of life (WHO-5 Well-Being Index). Results: Ninety-five subjects (74.7% males; mean [standard deviation] age, 9 [4.24]; range, 2-17.5 years) received PedPRM (2/5 mg) according to the double-blind phase dose, for 39 weeks with optional dose adjustment (2, 5, or 10 mg/day) after the first 13 weeks. After 52 weeks of continuous treatment (PedPRM-randomized group) subjects slept (mean [SE]) 62.08 (21.5) minutes longer (p = 0.007); fell asleep 48.6 (10.2) minutes faster (p < 0.001); had 89.1 (25.5) minutes longer uninterrupted sleep episodes (p = 0.001); 0.41 (0.12) less nightly awakenings (>50% decrease; p = 0.001); and better sleep quality (p < 0.001) compared with baseline. The placebo-randomized group also improved with PedPRM. Altogether, by the end of 39-week follow-up, regardless of randomization assignment, 55/72 (76%) of completers achieved overall improvement of ≥1 hour in total sleep time (TST), sleep latency or both, over baseline, with no evidence of decreased efficacy. In parallel, CSDI child sleep disturbance and caregivers' satisfaction of their child's sleep patterns (p < 0.001 for both), PSQI global (p < 0.001), and WHO-5 (p = 0.001) improved in statistically significant and clinically relevant manner (n = 72) compared with baseline. PedPRM was generally safe; most frequent treatment-related adverse events were fatigue (5.3%) and mood swings (3.2% of patients). Conclusion: PedPRM, an easily swallowed formulation shown to be efficacious versus placebo, is an efficacious and safe option for long-term treatment (up to 52 weeks reported here) of children with ASD and NGD who suffer from insomnia and subsequently improves caregivers' quality of life.

Efficacy and Safety of Pediatric Prolonged-Release Melatonin for Insomnia in Children With Autism Spectrum Disorder.

OBJECTIVE: To assess the efficacy and safety of novel pediatric-appropriate, prolonged-release melatonin minitablets (PedPRM) versus placebo for insomnia in children and adolescents with autism spectrum disorder (ASD), with or without attention-deficit/hyperactivity disorder (ADHD) comorbidity, and neurogenetic disorders (NGD). METHOD: A total of 125 children and adolescents (2-17.5 years of age; 96.8% ASD, 3.2% Smith-Magenis syndrome [SMS]) whose sleep failed to improve on behavioral intervention alone were randomized (1:1 ratio), double-blind, to receive PedPRM (2 mg escalated to 5 mg) or placebo for 13 weeks. Sleep measures included the validated caregivers' Sleep and Nap Diary (SND) and Composite Sleep Disturbance Index (CSDI). The a priori primary endpoint was SND-reported total sleep time (TST) after 13 weeks of treatment. RESULTS: The study met the primary endpoint: after 13 weeks of double-blind treatment, participants slept on average 57.5 minutes longer at night with PedPRM compared to 9.14 minutes with placebo (adjusted mean treatment difference PedPRM-placebo -32.43 minutes; p = .034). Sleep latency (SL) decreased by 39.6 minutes on average with PedPRM and 12.5 minutes with placebo (adjusted mean treatment difference -25.30 minutes; p = .011) without causing earlier wakeup time. The rate of participants attaining clinically meaningful responses in TST and/or SL was significantly higher with PedPRM than with placebo (68.9% versus 39.3% respectively; p = .001) corresponding to a number needed to treat (NNT) of 3.38. Overall sleep disturbance (CSDI) tended to decrease. PedPRM was generally safe; somnolence was more commonly reported with PedPRM than placebo. CONCLUSION: PedPRM was efficacious and safe for treatment of insomnia in children and adolescents with ASD with/without ADHD and NGD. The acceptability of this pediatric formulation in a population who usually experience significant difficulties in swallowing was remarkably high. Clinical trial registration information-Efficacy and Safety of Circadin in the Treatment of Sleep Disturbances in Children With Neurodevelopment Disabilities; http://clinicaltrials.gov/; NCT01906866.

Prolonged release melatonin for improving sleep in totally blind subjects: a pilot placebo-controlled multicenter trial.

INTRODUCTION: Melatonin, secreted by the pineal gland during the night phase, is a regulator of the biological clock and sleep tendency. Totally blind subjects frequently report severe, periodic sleep problems, with 50%-75% of cases displaying non-24-hour sleep-wake disorder (N24HSWD) due to inability to synchronize with the environmental day-night cycle. Melatonin immediate-release preparations are reportedly effective in N24HSWD. Here, we studied the efficacy and safety of prolonged-release melatonin (PRM), a registered drug for insomnia, for sleep disorders in totally blind subjects living in normal social environments. The primary endpoint was demonstration of clinically meaningful effects on sleep duration (upper confidence interval [CI] limit >20 minutes whether significant or not) to allow early decision-making on further drug development in this indication. TRIAL REGISTRATION: ClinicalTrials.gov registry - NCT00972075. METHODS: In a randomized, double-blind, placebo-controlled proof-of-principle study, 13 totally blind subjects had 2 weeks' placebo run-in, 6 weeks' randomized (1:1) PRM (Circadin(®)) or placebo nightly, and 2 weeks' placebo run-out. Outcome measures included daily voice recorded sleep diary, Clinical Global Impression of Change (CGIC), WHO-Five Well-being Index (WHO-5), and safety. RESULTS: Mean nightly sleep duration improved by 43 minutes in the PRM and 16 minutes in the placebo group (mean difference: 27 minutes, 95% CI: -14.4 to 69 minutes; P=0.18; effect size: 0.82) meeting the primary endpoint. Mean sleep latency decreased by 29 minutes with PRM over placebo (P=0.13; effect size: 0.92) and nap duration decreased in the PRM but not placebo group. The variability in sleep onset/offset and latency tended to decrease during PRM but not placebo treatment. The potentially beneficial effects of PRM persisted during the 2 weeks of discontinuation period, consistent with clock stabilizing effects. PRM was well-tolerated, adverse events were of mild or moderate severity and similar between PRM and placebo. CONCLUSION: Nightly use of PRM may potentially improve patient-reported sleep difficulties in totally blind individuals trying to adhere to normal social lifestyle. A larger study powered to demonstrate a statistically significant effect is warranted.

Add-on prolonged-release melatonin for cognitive function and sleep in mild to moderate Alzheimer's disease: a 6-month, randomized, placebo-controlled, multicenter trial.

PURPOSE: A link between poor sleep quality and Alzheimer's disease (AD) has recently been suggested. Since endogenous melatonin levels are already reduced at preclinical AD stages, it is important to ask whether replenishing the missing hormone would be beneficial in AD and whether any such effects would be related to the presence of sleep disorder in patients. PATIENTS AND METHODS: The effects of add-on prolonged-release melatonin (PRM) (2 mg) to standard therapy on cognitive functioning and sleep were investigated in 80 patients (men [50.7%], women [49.3%], average age 75.3 years [range, 52-85 years]) diagnosed with mild to moderate AD, with and without insomnia comorbidity, and receiving standard therapy (acetylcholinesterase inhibitors with or without memantine). In this randomized, double-blind, parallel-group study, patients were treated for 2 weeks with placebo and then randomized (1:1) to receive 2 mg of PRM or placebo nightly for 24 weeks, followed by 2 weeks placebo. The AD Assessment Scale-Cognition (ADAS-Cog), Instrumental Activities of Daily Living (IADL), Mini-Mental State Examination (MMSE), sleep, as assessed by the Pittsburgh Sleep Quality Index (PSQI) and a daily sleep diary, and safety parameters were measured. RESULTS: Patients treated with PRM (24 weeks) had significantly better cognitive performance than those treated with placebo, as measured by the IADL (P=0.004) and MMSE (P=0.044). Mean ADAS-Cog did not differ between the groups. Sleep efficiency, as measured by the PSQI, component 4, was also better with PRM (P=0.017). In the comorbid insomnia (PSQI ≥6) subgroup, PRM treatment resulted in significant and clinically meaningful effects versus the placebo, in mean IADL (P=0.032), MMSE score (+1.5 versus -3 points) (P=0.0177), and sleep efficiency (P=0.04). Median ADAS-Cog values (-3.5 versus +3 points) (P=0.045) were significantly better with PRM. Differences were more significant at longer treatment duration. PRM was well tolerated, with an adverse event profile similar to that of placebo. CONCLUSION: Add-on PRM has positive effects on cognitive functioning and sleep maintenance in AD patients compared with placebo, particularly in those with insomnia comorbidity. The results suggest a possible causal link between poor sleep and cognitive decline.

Effects of prolonged-release melatonin and zolpidem on postural stability in older adults.

OBJECTIVES: A prolonged-release formulation of melatonin (PR-M) is indicated for insomnia in patients aged 55 years and older. Because hypnotics result in impairments of body sway, it was important to evaluate the effect of 2 mg PR-M on postural stability in older adults at night. METHODS: Twenty-four healthy volunteers (12 women, 12 men, aged 55-64 years) completed a randomized, double-blind, single-dose, three-way crossover study of postural stability of PR-M 2 mg, zolpidem 10 mg (active control) or placebo. Subjects were tested for body sway 30 min before, 1.5 and 4 h after dosing. Parameters tested were the area of the 95% confidence ellipse enclosing the center of pressure (COP; [A95]) and COP path length. RESULTS: Zolpidem significantly increased the A95 (both eyes conditions at all time points) and path length of COP. PR-M had no effect on A95 (both "eyes closed" and "eyes open" conditions at all time points) compared with placebo and increased COP path length by 10% at 4 h post-dose in open but not closed eyes condition. No serious adverse events were observed. CONCLUSIONS: In older adults, evening PR-M intake did not impair postural stability during the night. The postural instability with zolpidem demonstrated assay sensitivity and validated the outcome.

Efficacy and safety of prolonged-release melatonin for insomnia in middle-aged and elderly patients with hypertension: a combined analysis of controlled clinical trials.

BACKGROUND: Add-on prolonged-release melatonin (PRM) in antihypertensive therapy has been shown to ameliorate nocturnal hypertension. Hypertension is a major comorbidity among insomnia patients. The efficacy and safety of PRM for primary insomnia in patients aged 55 years and older who are treated with antihypertensive drugs were evaluated. METHODS: Post hoc analysis of pooled antihypertensive drug-treated subpopulations from four randomized, double-blind trials of PRM and placebo for 3 weeks (N[PRM] = 195; N[placebo] = 197) or 28 weeks (N[PRM] = 157; N[placebo] = 40). Efficacy measurements included Leeds Sleep Evaluation Questionnaire scores of quality of sleep and alertness and behavioral integrity the following morning after 3 weeks, and sleep latency (daily sleep diary) and Clinical Global Impression of Improvement (CGI-I) after 6 months of treatment. Safety measures included antihypertensive drug-treated subpopulations from these four and three additional single-blind and open-label PRM studies of up to 1 year (N[PRM] = 650; N[placebo] = 632). RESULTS: Quality of sleep and behavior following wakening improved significantly with PRM compared with placebo (P < 0.0001 and P < 0.0008, respectively). Sleep latency (P = 0.02) and CGI-I (P = 0.0003) also improved significantly. No differences were observed between PRM and placebo groups in vital signs, including daytime blood pressure at baseline and treatment phases. The rate of adverse events normalized per 100 patient-weeks was lower for PRM (3.66) than for placebo (8.53). CONCLUSIONS: The findings demonstrate substantive and sustained efficacy of PRM in primary insomnia patients treated with antihypertensive drugs. PRM appears to be safe for insomnia in patients with cardiovascular comorbidity.

Prolonged-release melatonin for insomnia - an open-label long-term study of efficacy, safety, and withdrawal.

BACKGROUND: Prolonged-release melatonin (PRM) 2 mg is indicated for insomnia in patients aged 55 years and older. A recent double-blind placebo-controlled study demonstrated 6-month efficacy and safety of PRM in insomnia patients aged 18-80 and lack of withdrawal and rebound symptoms upon discontinuation. OBJECTIVE: To investigate the efficacy, safety, and withdrawal phenomena associated with 6-12 months PRM treatment. METHODS: Data from a prospective 6-12-month open-label study of 244 community dwelling adults with primary insomnia, who had participated in a placebo-controlled, double-blind dose-ranging trial of PRM. Patients received PRM nightly, followed by a 2-week withdrawal period. Main outcome measures were patient-reported sleep quality ratings (diary), adverse events, vital signs, and laboratory tests recorded at each visit, and withdrawal symptoms (CHESS-84 [Check-list Evaluation of Somatic Symptoms]). Nocturnal urinary 6-sulfatoxymelatonin excretion, a measure of the endogenous melatonin production, was assessed upon discontinuing long-term PRM. RESULTS: Of the 244 patients, 36 dropped out, 112 completed 6 months of treatment, and the other 96 completed 12 months of treatment. The mean number of nights by which patients reported sleep quality as "good" or "very good" was significantly higher during PRM than before treatment. There was no evidence of tolerance to PRM. Discontinuation of PRM was not associated with rebound insomnia or withdrawal symptoms; on the contrary, residual benefit was observed. PRM was well tolerated, and there was no suppression of endogenous melatonin production. CONCLUSION: Results support the efficacy and safety of PRM in primary insomnia patients aged 20-80 throughout 6-12 months of continuous therapy. PRM discontinuation even after 12 months was not associated with adverse events, withdrawal symptoms, or suppression of endogenous melatonin production.