Sally has an additive you can mix with your color that's supposed to help get the red out. Other then that, I agree that an ash brown (if brown is your ultimate goal) would help cancel out the red.

BUT, that is such a powerful (and stunning, to steal cg's apt choice of word) color that I would only really recommend an expert colorist. As they say, color won't lift color, so if you really want it gone, you'll need someone who can do a high lift and then place the color you want.