If successful, 786 is a game changer and in 2014 looked as though it would be the 1st drug to market for Agitation in Alz. That's why Otsuka bought Avanir. They took a risk and it played out poorly as 786 is looking at a 2021 approval now and 4-5 other drugs will be approved prior (Otsuka's Rexulti will have it by end of 2017). Yes, a couple of those are atypical antipsychotics, but that won't matter as long as they have the indication.

And Otsuka also bought Avanir because of all the potential uses of the Dextromethorphin/Quinidine combo, which made it much more attractive. Unfortunately, treatment resistant depression failed badly.

Elto is so far behind the 8 ball and forgotten, my guess is no one will even take the time to conduct trials. IMO.