Controlled release compositions
AssigneeBritish Technology Group Limited
InventorJohn Michael Newton
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Abstract
A controlled release composition comprising an extruded core of active material and excipients, said core being coated in a water insoluble coating. Preferably the core comprises a pharmaceutically acceptable active ingredient together with microcrystalline cellulose, a clay such as kaolin and a binder such as poly(vinyl-pyrrolidine).
Claims30
A controlled release composition in the form of an extruded rod or tube of active material and microcrystalline cellulose and clay excipients, said rod or tube being of at least 2 mm external diameter and being coated with a material having solubility in water such that dissolution of active material proceeds in a controlled manner in aqueous medium and the coated rod or tube retains its structural integrity during the period over which the active material is to be released.
A process for the preparation of a controlled release composition in the form of a rod or tube, said method comprising the steps of:
- extruding a wet mass comprising active material and microcrystalline cellulose and clay excipients through a die to form a rod or tube of at least 2 mm external diameter;
- and
- coating the rod or tube with a material having solubility in water such that dissolution of active material from the rod or tube proceeds in a controlled manner in aqueous medium and the coated rod or tube retains its structural integrity during the period over which the active material is to be released.
A controlled release composition in the form of an extruded rod or tube of active material and microcrystalline cellulose and clay excipients, said rod or tube being coated with a material having solubility in water such that dissolution of active material proceeds in a controlled manner in aqueous medium and the coated rod or tube retains its structural integrity during the period over which the active material is to be released, wherein the release of the active material is at a constant rate over a prolonged period.
A process for the preparation of a controlled release composition in the fore of a rod or tube, wherein a wet mass comprising active material and microcrystalline cellulose and clay excipients is extruded through a die to fore a rod or tube and the rod or tube is coated with a material having solubility in water such that dissolution of active material from the rod or tube proceeds in a controlled manner in aqueous medium and the coated rod or tube retains its structural integrity during the period over which the active material is to be released, wherein the release of the active material is at a constant rate over a prolonged period.
Dependencies are inferred from the claim text.