Preheat the oven to 350 degrees F (175 degrees C). Grease a 1 1/2-quart loaf pan.
Stir cornbread mix, water, pumpkin puree, egg, oil, sugar, oat bran, molasses, vanilla, and pumpkin pie spice together until mixed thoroughly. Pour into the loaf pan.
Bake in the preheated oven until a toothpick inserted into the center comes out clean, 50 to 60 minutes.
