The invention provides a balloon catheter formed with a plurality of depressions. The balloon is coated with a matrix incorporating a therapeutic substance, which fills the depressions. When the balloon is expanded within a body lumen, the therapeutic substance may diffuse into the lumen wall, or all or a portion of the coating transfers to the lumen wall. A lattice frame may surround the balloon, applied prior to coating if the coating is to transfer, operative to maintain a more linear balloon profile during inflation, promoting more even transfer pressure. A contrast dye is incorporated into the transferred coating, enabling ready location and inspection of the treated lumen area.
