Alex Kolevzon, MD, Clinical Director of the Seaver Autism Center at Mount Sinai, discusses Phelan-McDermid syndrome and the JAG201 study.
Phelan-McDermid syndrome is a rare, genetic form of autism spectrum disorder. It is caused by a variant in the SHANK3 gene on chromosome 22. Medical, intellectual, and behavioral challenges are observed in patients with Phelan-McDermid syndrome. While signs and symptoms vary by patient, common ones include:
- Hypotonia
- Developmental delays
- Absent or delayed speech
- Sleep disturbance
- Poor feeding
- Gastrointestinal problems
- Seizures
As explained by Dr. Kolevzon, Phelan-McDermid syndrome is usually diagnosed through genetic testing. While genetic testing is recommended for all patients with autism, challenges to its access still exist.
Currently, there are no therapies that target and modify Phelan-McDermid syndrome. Management of the disease includes those used in treating patients with autism such as speech therapy, occupational therapy, and behavioral therapy. Individualized symptom management is also common.
Recently, the U.S. Food and Drug Administration approved the Investigational New Drug Application for JAG201, a gene therapy targeting autism spectrum disorder and Phelan-McDermid syndrome by delivering functional SHANK3 via the AAV9 vector. Given the approval, Jaguar Gene Therapy aims to begin a Phase 1 trial with adult patients who have autism spectrum disorder (ASD) and Phelan-McDermid syndrome who present a SHANK3 mutation or deletion. The trial is hopeful to start in the second half of 2024.
Dr. Alexander Kolevzon has served as a paid consultant for Jaguar Gene Therapy.
For more information on rare genetic conditions, visit https://checkrare.com/diseases/congenital-and-genetic-conditions/