Clinical trial of insulin-like growth factor-1 in Phelan-McDermid syndrome.

BACKGROUND: Phelan-McDermid syndrome (PMS) is caused by haploinsufficiency of the SHANK3 gene and is characterized by global developmental delays and autism spectrum disorder (ASD). Based on several converging lines of preclinical and clinical evidence supporting the use of insulin-like growth factor-1 (IGF-1) in PMS, this study aims to follow-up a previous pilot study with IGF-1 to further evaluate this novel therapeutic for core symptoms of ASD in children with PMS. METHODS: Ten children aged 5-9 with PMS were enrolled. Participants were randomized to receive IGF-1 or placebo (saline) using a 12-week, double-blind, crossover design. Efficacy was assessed using the primary outcome of the Aberrant Behavior Checklist-Social Withdrawal (ABC-SW) subscale as well as secondary outcome measures reflecting core symptoms of ASD. To increase power and sample size, we jointly analyzed the effect of IGF-1 reported here together with results from our previous controlled trail of IGF-1 in children with PMS (combined N = 19). RESULTS: Results on the ABC-SW did not reach statistical significance, however significant improvements in sensory reactivity symptoms were observed. In our pooled analyses, IGF-1 treatment also led to significant improvements in repetitive behaviors and hyperactivity. There were no other statistically significant effects seen across other clinical outcome measures. IGF-1 was well tolerated and there were no serious adverse events. LIMITATIONS: The small sample size and expectancy bias due to relying on parent reported outcome measures may contribute to limitations in interpreting results. CONCLUSION: IGF-1 is efficacious in improving sensory reactivity symptoms, repetitive behaviors, and hyperactivity  in children with PMS. Trial registration NCT01525901.

Cancer risk in individuals with autism spectrum disorder.

BACKGROUND: Whether individuals with autism spectrum disorders (ASDs) have a higher-than-expected risk of cancer remains unknown. PATIENTS AND METHODS: We carried out a population-based cohort study including 2.3 million individuals live-born to mothers from Nordic countries during 1987-2013 in Sweden with follow-up through 2016 (up to age 30 years). Individuals with ASD were ascertained through the Swedish National Patient Register. We estimated the relative risk of cancer in relation to ASD by odds ratios (ORs) and associated 95% confidence intervals (CIs) derived from logistic regression, after detailed adjustment for potential confounders. We also carried out a sibling comparison to address familial confounding and a genetic correlation analysis using the genome-wide association study summary statistics to address confounding due to potential polygenetic pleiotropy between ASD and cancer. RESULTS: We observed an overall increased risk of any cancer among individuals with ASD (OR 1.3, 95% CI 1.2-1.5), compared with individuals without ASD. The association for any cancer was primarily noted for narrowly defined autistic disorder (OR 1.7, 95% CI 1.3-2.1) and ASD with comorbid birth defects (OR 2.1, 95% CI 1.5-2.9) or both birth defects and intellectual disability (ID; OR 4.8, 95% CI 3.4-6.6). An association was also suggested for ASD with comorbid ID (OR 1.4; 95% CI 0.9-2.1), but was not statistically significant. ASD alone (i.e. without comorbid ID or birth defects) was not associated with an increased risk of any cancer (OR 1.0, 95% CI 0.8-1.2). Sibling comparison and genetic correlation analysis showed little evidence for familial confounding or confounding due to polygenetic pleiotropy between ASD and cancer. CONCLUSIONS: ASD per se is not associated with an increased risk for cancer in early life. The increased cancer risk among individuals with ASD is likely mainly attributable to co-occurring ID and/or birth defects in ASD.

A proof-of-concept study of growth hormone in children with Phelan-McDermid syndrome.

BACKGROUND: Phelan-McDermid syndrome (PMS) is caused by 22q13 deletions including SHANK3 or pathogenic sequence variants in SHANK3 and is among the more common rare genetic findings in autism spectrum disorder (ASD). SHANK3 is critical for synaptic function, and preclinical and clinical studies suggest that insulin-like growth factor-1 (IGF-1) can reverse a range of deficits in PMS. IGF-1 release is stimulated by growth hormone secretion from the anterior pituitary gland, and this study sought to assess the feasibility of increasing IGF-1 levels through recombinant human growth hormone (rhGH) treatment, in addition to establishing safety and exploring efficacy of rhGH in children with PMS. METHODS: rhGH was administered once daily for 12 weeks to six children with PMS using an open-label design. IGF-1 levels, safety, and efficacy assessments were measured every 4 weeks throughout the study. RESULTS: rhGH administration increased levels of IGF-1 by at least 2 standard deviations and was well tolerated without serious adverse events. rhGH treatment was also associated with clinical improvement in social withdrawal, hyperactivity, and sensory symptoms. LIMITATIONS: Results should be interpreted with caution given the small sample size and lack of a placebo control. CONCLUSIONS: Overall, findings are promising and indicate the need for larger studies with rhGH in PMS. Trial registration NCT04003207. Registered July 1, 2019, https://clinicaltrials.gov/ct2/show/NCT04003207 .

Parent-reported measure of repetitive behavior in Phelan-McDermid syndrome.

BACKGROUND: Phelan McDermid syndrome (PMS) is a neurogenetic condition associated with a high prevalence of intellectual disability (ID) and autism spectrum disorder (ASD). This study provides a more comprehensive and quantitative profile of repetitive behaviors within the context of ID seen with the condition. METHODS: Individuals age 3-21 years with a confirmed PMS diagnosis participated in a multicenter observational study evaluating the phenotype and natural history of the disorder. We evaluated data collected from this study pertaining to repetitive behaviors from the Repetitive Behavior Scales-Revised (RBS-R). RESULTS: There were n = 90 participants who were part of this analysis. Forty-seven percent (n = 42/90) were female, and the average age at baseline evaluation was 8.88 ± 4.72 years. The mean best estimate IQ of the cohort was 26.08 ± 17.67 (range = 3.4-88), with n = 8 with mild ID (or no ID), n = 20 with moderate ID, and n = 62 with severe-profound ID. The RBS-R total overall score was 16.46 ± 13.9 (compared to 33.14 ± 20.60 reported in previous studies of ASD) (Lam and Aman, 2007), and the total number of items endorsed was 10.40 ± 6.81 (range = 0-29). After statistical correction for multiple comparisons, IQ correlated with the RBS-R stereotypic behavior subscale score (rs = - 0.33, unadjusted p = 0.0014, adjusted p = 0.01) and RBS-R stereotypic behavior total number of endorsed items (rs = - 0.32, unadjusted p = 0.0019, adjusted p = 0.01). IQ did not correlate with any other RBS-R subscale scores. CONCLUSIONS: The RBS-R total overall score in a PMS cohort appears milder compared to individuals with ASD characterized in previous studies. Stereotypic behavior in PMS may reflect cognitive functioning.

A randomized controlled trial of intranasal oxytocin in Phelan-McDermid syndrome.

BACKGROUND: Phelan-McDermid syndrome (PMS) is a rare neurodevelopmental disorder caused by haploinsufficiency of the SHANK3 gene and characterized by global developmental delays, deficits in speech and motor function, and autism spectrum disorder (ASD). Monogenic causes of ASD such as PMS are well suited to investigations with novel therapeutics, as interventions can be targeted based on established genetic etiology. While preclinical studies have demonstrated that the neuropeptide oxytocin can reverse electrophysiological, attentional, and social recognition memory deficits in Shank3-deficient rats, there have been no trials in individuals with PMS. The purpose of this study is to assess the efficacy and safety of intranasal oxytocin as a treatment for the core symptoms of ASD in a cohort of children with PMS. METHODS: Eighteen children aged 5-17 with PMS were enrolled. Participants were randomized to receive intranasal oxytocin or placebo (intranasal saline) and underwent treatment during a 12-week double-blind, parallel group phase, followed by a 12-week open-label extension phase during which all participants received oxytocin. Efficacy was assessed using the primary outcome of the Aberrant Behavior Checklist-Social Withdrawal (ABC-SW) subscale as well as a number of secondary outcome measures related to the core symptoms of ASD. Safety was monitored throughout the study period. RESULTS: There was no statistically significant improvement with oxytocin as compared to placebo on the ABC-SW (Mann-Whitney U = 50, p = 0.055), or on any secondary outcome measures, during either the double-blind or open-label phases. Oxytocin was generally well tolerated, and there were no serious adverse events. LIMITATIONS: The small sample size, potential challenges with drug administration, and expectancy bias due to relying on parent reported outcome measures may all contribute to limitations in interpreting results. CONCLUSION: Our results suggest that intranasal oxytocin is not efficacious in improving the core symptoms of ASD in children with PMS. Trial registration NCT02710084.

Brief Report: Sensory Reactivity in Children with Phelan-McDermid Syndrome.

Phelan-McDermid syndrome (PMS), a monogenic form of autism spectrum disorder (ASD), results from deletion or mutation of the SHANK3 gene. Atypical sensory reactivity is now included in the diagnostic criteria for ASD. Examining the sensory phenotype in monogenic forms of ASD, such as PMS, may help identify underlying mechanisms of sensory reactivity. Using the Short Sensory Profile, the current study compared sensory reactivity in 24 children with PMS to 61 children with idiopathic ASD (iASD). Results suggest that children with PMS show more low energy/weak symptoms and less sensory sensitivity as compared to children with iASD. This study is the first to demonstrate differences in sensory reactivity between children with PMS and iASD, helping to refine the PMS phenotype.

Initial severity and efficacy of risperidone in autism: Results from the RUPP trial.

BACKGROUND: Risperidone is a common psychopharmacological treatment for irritability in autism spectrum disorder (ASD). It is not well-established how effective risperidone is across the initial symptom severity range. This study aims to examine the influence of baseline severity on the efficacy of risperidone in the treatment of ASD. METHODS: Participants were from the NIMH funded RUPP multisite, randomized, double-blind trial that compared risperidone to placebo to treat autistic disorder with severe tantrums, aggression, or self-injury. Participants were aged 5 to 17, and randomly assigned to risperidone (n=49) or placebo (n=52). Baseline and change scores were computed with the Aberrant Behavior Checklist (ABC) parent assessed scales with irritability as the primary outcome, as well as the clinician assessed ABC Irritability subscale, and Clinical Global Impression Scale. RESULTS: The relationship between baseline severity and change scores for the risperdone and placebo groups was examined with eight competing three-level mixed-effects models for repeated measure models. Significant (P<0.01) interactions between treatment and baseline severity were observed for parent ABC ratings of irritability and lethargy only. Greater magnitudes of the differences between risperidone and placebo were observed from moderate to very severe baseline severity on irritability and lethargy. Initial severity values over approximately 30 had a strong effect on symptom change [irritability: effect size (ES)=1.9, number needed to treat (NNT)=2, lethargy ES=0.9, NNT=5]. CONCLUSIONS: Parents may expect benefits of risperidone on irritability and lethargy with moderate to severe symptoms of ASD. TRIAL REGISTRATION: Registry name: ClinicalTrials.gov, trial identifier: NCT00005014, URL: http://www.clinicaltrials.gov/ct2/show/NCT00005014?term=NCT00005014&rank=1, registered on March 31, 2000.

Postprandial sleep in healthy men.

Twenty-one healthy men between 18 and 30 years of age were studied to determine the effects of midday food intake on sleep. Twelve subjects were administered liquid carbohydrate meals at lunchtime on 2 consecutive days. Subjects slept on 22 of the 24 study days for an average of 93 minutes during 3 hours of postprandial polysomnographic recording. Nine subjects were used as controls and were deprived of a lunch meal. Six of the nine subjects slept for an average of 30 minutes during the postprandial period. This time was significantly shorter than that of subjects in the meal condition (p < 0.005). There was no difference in latency to sleep onset following food intake between the two study groups. The results of this study suggest that lunchtime food intake does not promote the initiation of sleep, but that it does increase the duration of sleep episodes occurring during the postprandial period.