First approved treatment for Rett syndrome: a potential hope for patients with MECP2 duplication syndrome?

The 10th of March 2023 sets a very important date in the rare disease community.

Trofinetide has been approved by the FDA for treatment of patients with Rett Syndromemaking it the first treatment ever for Rett syndrome. The drug, marketed under the name Daybue™, is expected to be commercially available in the US by the end of April 2023 for patients older than 2 years old.

Trofinetide is a tripeptide derived from a protein called insulin-like growth factor 1 (IGF-1). It can be administered orally. This drug is thought to reduce the inflammation and improve the communication between neurons in the brain, which is impaired in individuals with Rett syndrome. Phase III clinical trials have shown that Trofinetide improves various symptoms of Rett syndrome, such as improving social communication, behavior, and hand function.

While the underlying genetic cause of MECP2 duplication syndrome (MDS) is different from that of Rett syndromeBoth disorders involve mutation on the MECP2 gene. Rett syndrome affects mainly girls, and has too little active MeCP2 protein, while MDS, mostly diagnosed in boys, leads to higher levels of the protein. Interestingly, both Rett and MDS cause impaired brain development and function, resulting in similar symptoms, such as intellectual disability, coordination problems and seizures.

Therefore, scientific advances on Rett syndrome contribute to increasing knowledge on the other ones. The approval of Daybue™ opens the door to further research into the use of Trofinetide in patients with MECP2 duplication syndrome.

The fight is not over for MECP2 duplication syndrome. Contribute to advancing research on a treatment for MDS by donating, raising awareness on the syndrome, and joining our actions!