You need a good solvent solution, so the coating can dissolve in the solution and you can wipe it off.
Like alcohol and that kind of stuff, although I think alcohol (ethanol) isn't strong enough to do the trick.
You could try aceton (nail polish remover) although really aggressive solvent, glass can resist it, but plastic can't. So don't spill on plastic stuff around the lens.
Aceton is really nasty on plastic...
Better try it out first on a cheap (non plastic) lens, or a little part in the corner on the lens...