PROCESS FOR OBTAINING GASTROINTESTINAL DRAGS WITH DELAYED OR DIRECTED EFFECT

摘要

1428426 Sustained release compositions; diagnostic devices PURDUE RESEARCH FOUNDATION 5 June 1973 [9 June 1972] 26662/73 Heading A5B A sustained release medicament formulation with prolonged gastric residence comprises (a) a medicament core and (b) a pharmaceutically acceptable coating on the core comprising a crosslinked polymeric film which comprises a prepolymer crosslinked with a cross-linking agent at a ratio of 8 parts by weight of prepolymer to 0.15 to 4 parts by weight of crosslinking agent, the prepolymer being a copolymer of (i) 20-90 parts by weight of a substituted or unsubstituted unsaturated dicarboxylic acid or acid anhydride having 1 to 3 carbon atoms between the two carboxylic groups, and (ii) 10-80 parts by weight of an alkene of 2 to 6 carbon atoms, styrene or an alkyl vinyl ether in which the alkyl radical contains 1 to 16 carbon atoms, the polymeric film being waterhydratable, water-permeable and swellable in the presence of gastric fluids. A large number of active ingredients are specified as being suitable for use in the medicament core. The core may also be coated with a binary polymeric film including a pharmaceutically acceptable, substantially water-insoluble polymeric component and a pharmaceutically acceptable polymeric component as defined in (b) above. The medicament core may be replaced by a diagnostic device such as a Heidelberg capsule.