There shouldn't be any negative reaction between the two. But I suggest you add lemon juice to the egg-white. Even better, follow up with Mayonnaise mask, which also contains eggs but vinegar to help exfoliate and lighten skin.

Thanks for the reply. I do ask however, whens it best to use it, I mean whether its better to use it after the three steps or after the benzoyl peroxide (Step 1) and before the toner (Step 2). Thanks again.

Use the mask before you begin your regimen. Otherwise, you'll only end up washing them down the drain.

1) Mask
2) Leave on 15-30 minutes
3) Wash face
4) Begin the usual regimen routine