Preheat oven to 350 degrees.
Prepare a loaf pan with nonstick spray.
Mix together sugar and 1 teaspoon of the pumpkin pie spice in a small bowl
Separate dough into individual biscuits. Flatten out biscuits, then spread about 1 tablespoon pumpkin pie mix on top of each.
Sprinkle each biscuit with pumpkin spice-sugar mixture, then continue layering until you have 4 piles of 5 biscuits.
Stack the biscuits in a row in the loaf pan, ensuring that the sides without filling are on the ends that are touching the pan.
Bake 40-45 minutes, or until biscuits are baked through, and the loaf is deep golden brown.
Cool in pan 10 minutes, then turn loaf out of the pan onto a plate or cutting board to serve.
To make the glaze, mix together the powdered sugar, milk, vanilla extract, and remaining pumpkin pie spice in a small bowl.
Drizzle evenly over the warm loaf, then serve immediately.