Preheat the oven to 350 F. Grease a large loaf pan.
In a medium bowl, whisk together flour, baking powder and baking soda.
In a large bowl, whisk the sugar and butter until well combined. Add in the eggs, vanilla and yogurt and mix thoroughly. Mix the dry ingredients into the wet ingredients, stirring until just combined.
Fold the peaches into the batter. Pour the batter into the prepared pan.
Mix together the butter, flour, oats, brown sugar and cinnamon. Crumble the butter together with your hands or a pastry blender until the mixture becomes coarse crumbs. Pour on top of batter in the prepared pan.
Bake for 40-50 minutes, until golden brown and a toothpick inserted into the center comes out clean or with a few moist crumbs. If the bread appears to be browning too quickly before the center is fully baked, put tin foil over it. Remove pan from oven and set it on a rack. Cool the bread before slicing.