Patent ID: 8043630

Claim:
A method for administering to a subject a water soluble drug that is preferentially absorbed in the upper gastrointestinal tract comprising, orally administering a controlled-release oral drug dosage form, wherein the dosage form comprises: (a) a core comprising a first solid polymeric matrix with said drug dispersed therein, and (b) a shell substantially completely encasing said core, said shell comprising a second solid polymeric matrix that swells upon imbibition of water to a size large enough to promote retention in the stomach while the stomach is in a fed mode, and said shell having a drug:polymer weight ratio that is less than that of said core, said shell having a thickness that is at least about 0.5% of the longest linear dimension of said dosage form, said second polymeric matrix being of a material and thickness relative to said core such that when said dosage form is immersed in gastric fluid, said drug is released from said dosage form into said gastric fluid at a controlled rate limited at least in part by diffusion of said drug through said shell to an extent that at least about 40% of said drug remains unreleased one hour after such immersion has begun and substantially all of said drug is released within about twenty-four hours after such immersion has begun, said shell remaining intact during substantially the entire period of drug release, wherein the drug has a beneficial biological effect in the treatment of various diseases.