Drug Improves Social Function in Fragile X SyndromeLast Updated: September 20, 2012. A γ-aminobutyric acid type B agonist, STX209 (Arbaclofen), can significantly improve social function in patients with fragile X syndrome, according to a study published in the Sept. 19 issue of Science Translational Medicine.
THURSDAY, Sept. 20 (HealthDay News) -- A γ-aminobutyric acid type B (GABAB) agonist, STX209 (Arbaclofen), can significantly improve social function in patients with fragile X syndrome, according to a study published in the Sept. 19 issue of Science Translational Medicine.
Elizabeth M. Berry-Kravis, M.D., Ph.D., from the Rush University Medical Center in Chicago, and colleagues randomly assigned 63 patients (55 male; 6 to 39 years old) with fragile X syndrome with a full mutation in the FMR1 gene on the X chromosome (>200 CGG triplet repeats) to placebo or STX209 in a crossover study.
The researchers found that STX209 had no significant effect on irritability as measured with the Aberrant Behavior Checklist (ABC)-Irritability subscale. There was improvement noted on the visual analog scale rating of parent-nominated problem behaviors, with positive trends in numerous global measures. Using the newly validated ABC-Social Avoidance Scale, there was a significant beneficial treatment effect. Significant improvement in social function was observed by several additional assessments in a subgroup of 27 patients with more severe social impairment. The drug was well tolerated, with sedation and headache as the most common side effects (8 percent incidence).
"This study will help to signal the beginning of a new era of targeted treatments for genetic disorders that have historically been regarded as beyond the reach of pharmacotherapy," Berry-Kravis said in a statement. "It will be a model for treatment of autism, intellectual disability, and developmental brain disorders based on understanding of dysfunction in brain pathways, as opposed to empiric treatment of symptoms. We hope mechanistically-based treatments like STX209 ultimately will be shown to improve cognitive functioning in longer-term trials."
Several authors are employees of or disclosed financial ties to Seaside Therapeutics, which funded the study and manufactures STX209.