Mechanistic diversity in the pipeline for fragile X syndrome

The 13 clinical and preclinical therapies in development for fragile X syndrome map to at least as many therapeutic mechanisms. What most of the programs share is use of a small molecule to ameliorate behavioral symptoms through effects on neurotransmission, but at least two preclinical companies are taking a gene therapy approach.

Fragile X syndrome (FXS) is a developmental disorder caused by a CGG triplet repeat expansion in FMR1, which results in epigenetic silencing of the gene and loss of protein expression. It is the leading cause of inherited intellectual disability...