HuidaGene Therapeutics used CRISPR gene-editing (Cas13) to modify genes in the brain for the first time, successfully treating a 9-year-old with MECP2 duplication syndrome.

This is a tentative result, it's only one patient, and large scale trials would be needed to confirm it. Still, if it is confirmed it's a significant breakthrough. HuidaGene is also working on treatments for Huntington's Disease, Duchenne muscular dystrophy (DMD among other diseases. It's also working on various Ophthalmology related conditions.