Rachel, if it is a true italic, then I would say no. The individual character shapes, and thus the interfit, are different. It might be possible with an oblique version of a roman face. However, since the widths are effectively measured on the baseline, the point of origin of each character would have to be shifted to the left inorder to create a kind of “kerned” character.

Charles

Not the sidebearings, but perhaps the width and also some kerning pairs. It all depends on how the italic looks. A good thing when it comes to space Italics is to use the measurement line on a good positioin in the vertical middle as a guide for straight stems. Also keep in mind that the italic should be able to work with the roman, so normally after slanting I shift all the glyphs a little bit to the left when the Italic is based on the Roman version.