It depends what you're looking for, if you're looking for strength then 5x5 works well, but usually you need to drop it to 3x3 as the weights start to push you close to failure. For strength try to avoid failure.
If you're using the routine to pump up, then I'm afraid I have no advice as I'm a powerlifter not a body builder.
Try doing the routine like this though
Keep the same weight for all five sets. As the weight gets difficult drop to 3x5, again keeping the weight the same, and eventually drop to 3x3.
In my mind what you're doing is actually a warm up and 1x5
If all out strength was your goal I'd finish it off with a peaking cycle by dropping to 2x2, then 1x2 and eventually 1x1 for the final week or two
Jay