The present invention relates to controlled release drug delivery systems. In one embodiment, the present invention relates to controlled release drug delivery systems comprising a combination of at least one polyacrylic acid and at least one enteric polymer. In another embodiment, the present invention relates to a controlled release pharmaceutical composition comprising the combination of at least one active pharmaceutical ingredient and a controlled release drug delivery system, where the controlled release drug delivery system comprises the combination of at least one polyacrylic acid and at least one enteric polymer.