With a $90,000 grant from FRAXA Research Foundation funded during 2014-2015, Dr. Frank Kooy and colleagues at the University of Antwerp are conducting a double blind crossover trial of ganaxolone in patients with fragile X syndrome. Results of this study were mixed (see Marinus: Results from Phase 2 Exploratory Clinical Study Support Continued Development of Ganaxolone in Fragile X Syndrome.
Of the many genes known to be regulated by FMRP, the gamma-aminobutyric acid receptor A (GABA(A)), is gaining attention as a potential target for the treatment of FXS. Mounting evidence suggests decreased expression and functioning of GABA(A) is involved in the pathophysiology of FXS. Non-selective GABA(A) agonism in animal models of FXS has been associated with normalization of morphological features, GABA(A) expression, and behavior. However, the clinical use of these agents in fragile X is associated with unwanted side-effects, such as sedation, dulling of cognition, and occasional paradoxical agitation, which limits their use. Given the limitations in available GABA(A)-based treatment of FXS, this group plans to investigate a novel selective GABA(A) agonist in a mouse model of FXS. This agent has the potential to relieve many symptoms of fragile X without the unwanted side effects.
With a $100,000 grant from FRAXA Research Foundation, Drs. Joshua Corbin and Molly Huntsman from the Children’s National Medical Center examined the role of a particular class of brain cells (inhibitory interneurons) that dampen excessive activity in the “emotional center of the brain” (the amydala). This inhibition is deficient in fragile X, and so they are looked for ways to remedy this. This is particularly interesting to parents of children who are overly anxious and emotional. They worked with Dr. Walter Kaufmann, a clinician at Kennedy Krieger Institute in Maryland.