Claims for Patent: 9,144,547

Summary for Patent: 9,144,547

Title:	Oral dosage form for controlled drug release
Abstract:	An oral dosage form comprising, (i) an erodable core, which core comprises a pharmaceutically active weak base or a pharmaceutically acceptable salt or solvate thereof; and (ii) an erodable coating surrounding said core, which coating comprises one or more openings extending substantially completely through said coating but not penetrating said core and communicating from the environment of use to said core; characterized in that release of the pharmaceutically active weak base or a pharmaceutically acceptable salt or solvate thereof from the dosage form occurs through the said opening(s) by the erosion of said erodable core and through erosion of said erodable coating under pre-determined pH conditions; a process for preparing such a dosage form and the use of such a dosage form in medicine.
Inventor(s):	Li; Chi Leung (Harlow, GB), Martini; Luigi (Harlow, GB), Re; Vincenzo (Harlow, GB), Willy; Helen Anne (Harlow, GB)
Assignee:	Glaxo Group Limited (Brentford, Middlesex, GB)
Application Number:	12/966,323
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 9,144,547
Patent Claims:	1. A tablet oral dosage form comprising: (i) an erodable core, which core comprises a pharmaceutically active weak base or a pharmaceutically acceptable salt or solvate thereof; and (ii) a pH-dependent erodable coating around said core, which coating has a thickness in the range 0.05 to 0.5 mm and comprises one or more openings, wherein said openings are circular, drilled openings extending substantially completely through said coating but not penetrating said core and communicating from the environment of use to said core and have a diameter in the range 0.5 mm to 8 mm, wherein said openings comprise about 10 to 70% of the total face area of the dosage form; wherein release of the pharmaceutically active weak base or a pharmaceutically acceptable salt or solvate thereof from the dosage form occurs: through the one or more openings by the erosion of said erodable core and through erosion of said erodable coating at pH>4.5, wherein said erodable coating dissolves at pH>4.5 to expose all of said core to erosion. 2. The oral dosage form according to claim 1, wherein the erodable coating is selected from a polymethacrylate polymer, coprocessed polyvinylacetate phthalate, cellulose acetate trimellitate, cellulose acetate phthalate, shellac, a hydroxyropyl-methylcellulose phthalate polymer and their copolymers, and blends thereof. 3. The oral dosage form according to claim 1, wherein the erodable coating comprises two drilled openings. 4. The oral dosage form according to claim 1, wherein the erodable core is in a multi-layered form. 5. The oral dosage form according to claim 1, wherein the core is predominantly comprised of hydroxypropylmethyl cellulose and lactose. 6. The oral dosage form according to claim 1, wherein the pharmaceutically acceptable weak base is selected from bupropion, ondansetron, paroxetine, valaciclovir, and 5-[4-[2-(N-methyl-N-(2-pyridyl)amino)ethoxy]benzyl]thiazolidine-2,4-dione- , or a pharmaceutically acceptable salt or solvate thereof. 7. An oral dosage form according to claim 1, in which the pharmaceutically acceptable weak base is 5-[4-[2-(N-methyl-N-(2-pyridyl)amino)ethoxy]benzyl]thiazolidine-2,4-dione or a pharmaceutically acceptable salt or solvate thereof. 8. A process for the preparation of an oral dosage form according to claim 1, which process comprises: (a) preparing an erodable tablet core; (b) coating the core with a material with pH-dependent erodability; and (c) creating one or more openings in the coating, wherein said one or more openings extend substantially completely through said coating but not penetrating said core and communicating from the environment of use to said core.