Preheat the oven to 350 degrees F (175 degrees C).
Combine flour, brown sugar, baking soda, baking powder, pumpkin pie spice, cinnamon, and salt in a large bowl. Mix together egg whites, pumpkin puree, and vanilla extract in a separate bowl. Add wet ingredients to dry ingredients, mixing until combined. Fold in chocolate chips. Pour batter into a 9x5-inch loaf pan.
Bake in the preheated oven until a toothpick inserted into the center comes out clean, 45 to 50 minutes. Cool in the tin and then transfer to a wire rack to cool completely.