Preheat heavy skillet to medium temperature. Remove sausage from casing and add to skillet along with garlic and oregano. Cook, stirring until sausage is browned. Remove from heat and spoon sausage on paper towel-lined plate to drain if necessary and let cool.
On lightly flowered surface, roll pizza crust into 8 x 12-inch rectangle. Top center of dough with sausage mixture and then cheeses. Fold long sides of dough over sausage mixture and cheeses, overlapping. Enclose ends and brush with beaten egg.
Bake on baking sheet sprayed with non-stick cooking spray for 20-25 minutes, until golden brown. Cool slightly on a rack then cut into one-inch slices.