Claims for Patent: 5,541,171

Summary for Patent: 5,541,171

Title:	Orally administrable pharmaceutical composition
Abstract:	A solid dosage form, such as a capsule or tablet, containing a pharmacologically active agent is coated with an anionic polymer, which is insoluble in gastric juice and in intestinal juice below pH7 but soluble in colonic intestinal juice, in a sufficient amount that the oral dosage form remains intact until it reaches the colon. The preferred anionic polymer is a partly methyl esterified methacrylic acid polymer in which the ratio of free carboxylic groups to ester groups is about 1:2. The invention has particular application to dosage forms of prednisolone and salts thereof, indomethacin, ibuprofen, and, especially, 5-amino-salicylic acid.
Inventor(s):	Rhodes; John (Cardiff, GB7), Evans; Brian K. (Dinas Powis, GB7)
Assignee:	Tillotts Pharma AG (Ziefen, CH)
Application Number:	08/448,300
Patent Claims:	1. A non-sustained release orally administrable pharmaceutical composition for selectively administering 5-amino-salicylic acid or a pharmaceutically acceptable salt or ester thereof to the large intestine, the composition comprising a solid oral dosage form containing a pharmaceutically effective amount for the treatment of ulcerative colitis or Crohn's disease of said 5-amino-salicylic acid, ester or salt and said oral dosage form is coated with a 60 to 150 micron thick layer of an anionic copolymer of methacrylic acid and methacrylic acid methyl ester in which the ratio of free carboxyl groups to ester groups is about 1:2 and which is insoluble in gastric juice and in intestinal juice below pH 7 but soluble in colonic intestinal juice, whereby the oral dosage form remains intact until it reaches the colon and releases the 5-amino-salicylic acid to the right side of the colon. 2. A composition as claimed in claim 1 wherein the layer is 75 to 125 microns thick. 3. A composition as claimed in claim 2 wherein the layer is 80 to 100 microns thick. 4. A composition as claimed in claim 3 wherein the layer is 80 to 125 microns thick. 5. A composition as claimed in claim 1 wherein the layer is 80 to 125 microns thick. 6. A composition as claimed in claim 1 wherein the solid oral dosage form is a capsule or tablet. 7. A method of treating ulcerative colitis or Crohn's disease comprising orally administering to a person suffering therefrom a composition as claimed in claim 1. 8. A method as claimed in claim 7 wherein the layer is 80 to 125 microns thick. 9. An orally administrable pharmaceutical composition for selectively administering 5-amino-salicylic acid, or pharmaceutically acceptable salt or ester thereof, to the large intestine, comprising a solid oral dosage form containing a pharmaceutically effective amount for the treatment of ulcerative colitis or Crohn's disease of the colon of said 5-amino-salicylic acid, salt or ester, said solid oral dosage form, but not individual particles contained therein, being coated with a layer of composition containing an anionic copolymer of methacrylic acid and methacrylic acid methyl ester, in which the ratio of free carboxyl groups to ester groups is about 1:2, and which layer is insoluble in gastric juice and in intestinal juice below pH 7, but soluble in colonic intestinal juice, whereby the dosage form releases the 5-amino-salicylic acid, salt or ester to the right side of the colon. 10. The composition as claimed in claim 9 wherein the layer is 60 to 150 microns thick. 11. The composition as claimed in claim 10 wherein said layer contains said anionic copolymer as the only coating polymer. 12. The composition as claimed in claim 9 wherein the layer is 95 to 135 microns thick. 13. The composition as claimed in claim 12 wherein said layer contains said anionic copolymer as the only coating polymer. 14. The composition as claimed in claim 9 wherein the layer is 120 microns thick. 15. The composition as claimed in claim 14 wherein said layer contains said anionic copolymer as the only coating polymer. 16. The composition as claimed in claim 9 wherein the said oral dosage form is a capsule or tablet. 17. The composition as claimed in claim 9 wherein said individual particles are not coated. 18. A method of treating ulcerative colitis or Crohn's disease of the colon comprising orally administering to a person suffering therefrom the composition of claim 9 whereby the 5-amino-salicylic acid is released to the right side of the colon. 19. An orally administrable pharmaceutical composition for selectively administering 5-amino-salicylic acid, or pharmaceutically acceptable salt or ester thereof, to the large intestine, comprising a solid oral dosage form containing a pharmaceutically effective amount for the treatment of ulcerative colitis or Crohn's disease of the colon of said 5-amino-salicylic acid, salt or ester, said solid oral dosage form being coated with a layer of composition containing an anionic copolymer of methacrylic acid and methacrylic acid methyl ester, in which the ratio of free carboxyl groups to ester groups is about 1:2, and which layer is insoluble in gastric juice and in intestinal juice below pH 7, but soluble in colonic intestinal juice, whereby the dosage form releases the 5-amino-salicylic acid, salt or ester to the right side of the colon.