Riluzole in Fragile X Syndrome

Fragile X Syndrome (FXS) represents the most common inherited form of intellectual
disability. FXS is more common in males and the symptoms associated with the disorder are
more marked in males. FXS is associated with characteristic physical features, behaviors,
and comorbidities. Those with FXS often suffer from behavioral difficulties that include
anxiety-related symptoms (shyness, social phobia, obsessive-compulsive disorder (OCD)
symptoms), attention deficit hyperactivity symptoms (overarousal, hyperactivity,
distractibility, impulsivity) and aggressive/self-injurious behaviors.

Riluzole is approved by the FDA for use in treating amyotrophic lateral sclerosis (ALS) in
adults. Recently, riluzole has been the subject of several open-label studies describing
the use of the drug in treatment-resistant depression and OCD.

Given the overlap between repetitive behavior in FXS and symptoms of OCD, it is logical to
study riluzole in FXS given the compound's promise in ameliorating treatment-refractory
symptoms of OCD.