It is early days but it works temporarily. Even that may be good enough for a lot of therapy.
In the meantime we have a working explanation that is also promising and explains causation in a new manner. a whole range of agents may cause a problem in infants that is not easily reversed but is also with this drug reversible.
It is quite possible that a series of reversals and recoveries will slowly set up a triggering event that is a cure. So it is not over at all but only beginning. .