Fragile X syndrome is the most common inherited cause of intellectual disability and the most common known cause of autism. Fragile X syndrome is due to a gene mutation on the X chromosome that impacts the FMRP protein, which is responsible for regulating the synapses of nerve cells. The full mutation causes Fragile X syndrome. It is estimated that between one in 4,000 and one in 7,000 males and between one in 6,000 and one in 11,000 females have the full mutation. Generally, males are more severely affected, with approximately 50% of the females having some features of the syndrome. Clinically, Fragile X syndrome is characterized by intellectual handicap, hyperactivity and attentional problems, autistic symptoms, anxiety, emotional lability and epilepsy.
There are currently no approved medicines for Fragile X syndrome. The US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) have both granted Orphan Drug designation to Neuren for trofinetide in Fragile X syndrome. The FDA has also granted Fast Track designation.
Neuren has conducted a Phase 2 double-blind placebo-controlled clinical trial in subjects aged 12 to 45 years with Fragile X syndrome, in which treatment with trofinetide showed clinical improvement in many of the core symptoms.