Hi icetone--Unfortunately,
Nectar Elements doesn't support 64-bit AAX, so it won't run in 11. Do you have
Pro Tools 10? If so, it will run there, and the session file format is the same as Pro Tools 11, so you could do your vocal processing in 10, render the vocal track(s) with the effects, and then open the session in 11. I checked on the iZotope website, and the full version of
Nectar 2 does support 64-bit AAX, so will run on 11. You might want to check into whether there's a discounted upgrade from elements to
Nectar 2. Good luck!