A growth hormone can significantly improve the social impairment associated with autism spectrum disorder (ASD) in patients with a related genetic syndrome, according a new study.
The study results focus specifically on the use of insulin-like growth factor-1 (IGF-1) to treat Phelan-McDermid syndrome (PMS), a disorder caused by a deletion or mutation of the SHANK3 gene on chromosome 22.
Along with facing developmental and language delays and motor skill deficits, most people with PMS also have autism spectrum disorder.
"Ours is the first controlled trial of any treatment for Phelan-McDermid syndrome," said Alexander Kolevzon, clinical director at Seaver Autism Center at the Icahn School of Medicine at Mount Sinai.
"Because different genetic causes of ASD converge on common underlying chemical signalling pathways, the findings of this study may have implications for many forms of ASD," Kolevzon noted.
IGF-1 is a commercially available compound that promotes nerve cell survival, synaptic maturation and synaptic plasticity.
IGF-1 is safe, tolerable and associated with significant improvement in both social impairment and restrictive behaviours in people with Phelan-McDermid syndrome.
For the study, researchers enrolled nine children aged 5-15 years who were diagnosed with Phelan-McDermid syndrome.
All participants were exposed to three months of treatment with IGF-1 and three months of placebo, in random order.
Compared to placebo, the IGF-1 phase was associated with significant improvement in social withdrawal and restrictive behaviours.
"This clinical trial is part of a paradigm shift to develop targeted, disease modifying medicines specifically to treat the core symptoms of ASD," said Joseph Buxbaum, director of Seaver Autism Center and professor of psychiatry, genetics and genomic sciences and neuroscience at Mount Sinai.
"Results from this pilot trial will facilitate larger studies that more definitively inform efficacy and better targeted therapeutic treatments," Buxbaum stressed.
The study appeared in the journal Molecular Autism.