Preheat oven to 400 degrees. Brown the Italian Sausage, then mix in the cream cheese, cheddar and parmesan.
Spread that into a 9x11 baking dish and sprinkle with the oregano.
Pour the pizza sauce on, then top with the mozzarella and pepperoni.
Bake for about 15 minutes, (until the cheese is melted and the pepperoni is crispy).
Serve hot.