Patent ID: 8329215
Filing Date: 2012-12-11
Classification: A61K,A61P

Abstract:
1. A controlled-release oral drug dosage form for releasing a drug, comprising: (a) a core comprising a first polymeric matrix with said drug dispersed therein, and (b) a shell encasing said core, said shell comprising a second polymeric matrix having a drug:polymer weight ratio that is less than that of said core, the second matrix being a material and thickness relative to the core such that when the dosage form is immersed in gastric fluid, the shell swells upon imbibition of water to a size large enough to promote retention of the dosage form in a stomach in the fed mode, and the drug is released from the dosage form into the gastric fluid at a controlled rate by diffusion of the drug through the shell during substantially the entire period of drug release such that at least about 40% of said drug remains unreleased one hour after such immersion has begun, said shell remaining intact during substantially the entire period of drug release.