Fenobam belongs to a class of compounds known as mGluR5 antagonists. Neuropharm, a specialty pharmaceutical company based in the U.K., received Orphan Drug Designation in the US in 2006 for fenobam in the treatment of Fragile X, after acquiring rights to relevant data on the compound from FRAXA.

This trial was conducted in the US by Drs. Randi Hagerman of the UC Davis MIND Institute and Elizabeth Berry-Kravis of the RUSH University Medical Center, and initial results were first announced last summer. Their article in the Journal of Medical Genetics can be accessed free at: http://jmg.bmj.com/cgi/rapidpdf/jmg.2008.063701v1

Highlights of the study:

• This was a single dose open label study of fenobam in 6 male and 6 female adults with Fragile X.
• The study investigated the tolerability and pharmacokinetics of fenobam in this patient group.
• The study also investigated the effect of fenobam on efficacy related outcome measures. These measures had the potential to index efficacy after administration of a single dose of fenobam.
• Fenobam was well tolerated - there were no significant adverse reactions.
• Pharmacokinetic analysis showed that fenobam levels were dose dependent but variable.
• Four of 6 males and 2 of 6 females were responders. Potential positive effects on indices of social function such as eye contact were also noted.
• The investigators conclude that the favorable safety profile and the clinical effects noted in this study support implementation of further controlled trials of fenobam in adults with Fragile X.