| 摘要 |
The invention relates to a pH-dependent controlled release pharmaceutical composition, comprising a core, comprising at least one pharmaceutical active ingredient, which is an opioid, wherein the core is coated at least by one coating layer, controlling the release of the pharmaceutical composition, wherein the coating layer comprises a polymer mixture of i) 40 - 95 % by weight, based on dry weight of the polymer mixture, of at least one water insoluble essentially neutral vinyl polymer, and ii) 5 - 60 % by weight, based on dry weight of the polymer mixture, of at least one anionic polymer or copolymer, which is insoluble in a buffered medium below pH 4.0 and soluble at least in the range from pH 7.0 to pH 8.0, characterized in that the coating layer further contains 110 to 250 % by weight, calculated on dry weight of the polymer mixture, of a non-porous inert lubricant and the coating layer is present in an amount of at least 60 % by weight calculated on the weight of core. |
