Antisense therapy for Huntington's is in clinical trials now.

https://www.medpagetoday.com/neurology/generalneurology/7711...

It's not a cure, but shows the potential to significantly slow, and possible halt (in some), its onset and advancement.

Same therapeutic approach as Spinraza

https://www.nytimes.com/2016/12/30/business/spinraza-price.h...