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.

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 .

Examining the Efficacy of a Family Peer Advocate Model for Black and Hispanic Caregivers of Children with Autism Spectrum Disorder.

Autism spectrum disorder (ASD) affects individuals across all racial and ethnic groups, yet rates of diagnosis are disproportionately higher for Black and Hispanic children. Caregivers of children with ASD experience significant stressors, which have been associated with parental strain, inadequate utilization of mental health services and lower quality of life. The family peer advocate (FPA) model has been utilized across service delivery systems to provide family-to-family support, facilitate engagement, and increase access to care. This study used a randomized controlled design to examine the efficacy of FPAs in a racially and ethnically diverse sample. Results demonstrate significantly increased knowledge of ASD and reduced levels of stress for caregivers who received the FPA intervention as compared to treatment as usual.

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.