CA2373909A1 — Multilayer drug form release in the colon

USPTO Abstract

The invention relates to the use of a multilayer pharmaceutical product that substantially comprises a) a core contain-ing a pharmaceutically active substance, h) an inner coating consisting of a copolymer or a mixture of copolymers that are composed of 85 to 98 wt.- % of radically polymerized C1 to C4 alkyl esters of the acrylic or methacrylic acid and 15 to 2 wt.- % of (meth)acrylate monomers with a quaternary ammonium group in the alkyl group, and c) an outer coating consisting of a copolymer that is composed of 75 to 95 wt.- % of radically polymerized C1 to C4 alkyl esters of the acrylic or methacrylic acid and 5 to 25 wt.- % of (meth)acry-late monomers with an anionic group in the alkyl group. The inventive product is used for producing a pharmaceutical product that releases the active substance contained therein according to the USP release test, at pH 1.2 during 2 hours and subsequent rebuffering to pH 7.0, by less than 5 % after 2.0 hours after start of the test aid by 30 to 80 % after eight hours after start of the test.