Claims for Patent: 7,556,799

Summary for Patent: 7,556,799

Title:	Ion binding polymers and uses thereof
Abstract:	The present invention provides methods and compositions for the treatment of ion imbalances. In particular, the invention provides compositions comprising potassium binding polymers and pharmaceutical compositions thereof. Methods of use of the polymeric and pharmaceutical compositions for therapeutic and/or prophylactic benefits are disclosed herein. Examples of these methods include the treatment of hyperkalemia, such as hyperkalemia caused by renal failure and/or the use of hyperkalemia causing drugs.
Inventor(s):	Charmot; Dominique (Campbell, CA), Chang; Han Ting (Livermore, CA), Klaerner; Gerrit (Los Gatos, CA), Cope; Michael J. (Berkeley, CA), Liu; Mingjun (Campbell, CA), Liu; Futian (Sunnyvale, CA), Buysse; Jerry M. (Los Altos, CA)
Assignee:	Relypsa, Inc. (Santa Clara, CA)
Application Number:	11/096,209
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 7,556,799
Patent Claims:	1. A method for removing potassium from the gastrointestinal tract of a mammal in need thereof, the method comprising orally administering a pharmaceutical composition to the mammal, the pharmaceutical composition comprising a pharmaceutically acceptable excipient and a potassium-binding polymer or a salt thereof, the potassium-binding polymer being a crossliniked .alpha.-fluoroacrylic acid polymer, a crossliniked difluoromaleic acid polymer, or a salt thereof wherein said potassium removal is derived from repeat units selected from the group consisting of .alpha.-fluoroacrylic acid, difluoromaleic acid, vinylsulfonic acid, acrylic acid, vinyl phosphonate, vinyl-1,1-bisphosphonate, vinyl sulfonate, vinyl-1,2-disulfonate, itaconic acid, vinyl sulfamate, styrene sulfonate, .alpha.-hydroxyacrylic acid, a salt thereof, and a combination thereof in the crosslinked .alpha.-fluoroacrylic acid polymer, crosslinked difluoromaleic acid polymer, or salt thereof, whereby the pharmaceutical composition passes through the gastrointestinal tract of the mammal, and removes a therapeutically effective amount of potassium ion from the gastrointestinal tract of the mammal. 2. The method of claim 1 wherein the mammal is a human. 3. The method of claim 1 wherein the potassium-binding polymer is an alpha-fluoroacrylic acid polymer crossliniked with divinylbenzene, ethylene bisacrylamide, N,N'-bis(vinylsulfonylacetyl) ethylene diamine, 1,3-bis(vinylsulfonyl) 2-propanol, vinylsulfone, N,N'-methylenebisacrylamide polyvinyl ether, polyallylether, or a combination thereof. 4. The method of claim 1 wherein the potassium-binding polymer is an alpha-fluoroacrylic acid polymer crossliniked with divinyl benzene. 5. The method of claim 1 wherein the salt of the .alpha.-fluoroacrylic acid group is selected from Ca.sup.2+, H.sup.+, NH.sub.4.sup.+, Na.sup.+, or a combination thereof. 6. The method of claim 1 wherein said potassium-binding polymer has an in vitro potassium binding capacity of equal to or more than 6 mmol per gram of polymer at a pH of about 5.5. 7. The method of claim 1 wherein the in vivo potassium binding capacity is 1.5 mmol or more per gram of said polymer. 8. The method of claim 1 wherein the in vivo potassium binding capacity is 2 mmol or more per gram of said polymer. 9. The method of claim 1 wherein the in vivo potassium binding capacity is 4 mmol or more per gram of said polymer. 10. The method of claim 7 wherein the potassium binding capacity is calculated by measuring the amount of potassium in the feces after administration of the potassium binding polymer to a human patient. 11. The method of claim 1 wherein the pharmaceutical composition is administered in the form of a chewable tablet. 12. The method of claim 1 wherein the potassium-binding polymer is non-absorbed. 13. The method of claim 1 wherein the potassium-binding polymer is administered in a dose of about 10 grams/day to about 20 grams/day. 14. The method of claim 2 wherein the human is being treated with an agent that causes potassium retention, the agent causing potassium retention comprising an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. 15. The method of claim 14 wherein the potassium-binding polymer and the agent that causes potassium retention are administered simultaneously. 16. The method of claim 14 wherein the potassium-binding polymer and the agent that causes potassium retention are administered a few minutes apart, a few hours apart, or a few days apart. 17. A method for removing potassium from the gastrointestinal tract of a mammal in need thereof, the method comprising orally administering a pharmaceutical composition to the mammal, the pharmaceutical composition comprising a pharmaceutically acceptable excipient and a potassium-binding polymer, the potassium-binding polymer being a crossliniked alpha-fluoroacrylic acid polymer comprising a cationic counterion of Ca.sup.2+wherein said potassium removal is derived from repeat units selected from the group consisting of .alpha.-fluoroacrylic acid, difluoromaleic acid, vinylsulfonic acid, acrylic acid, vinyl phosphonate, vinyl-1,1-bisphosphonate, vinyl sulfonate, vinyl-1,2-disulfonate, itaconic acid, vinyl sulfamate, styrene sulfonate, .alpha.-hydroxyacrylic acid, a salt thereof, and a combination thereof in the crosslinked .alpha.-fluoroacrylic acid polymer, whereby the pharmaceutical composition passes through the gastrointestinal tract of the mammal, and removes a therapeutically effective amount of potassium ion from the gastrointestinal tract of the mammal. 18. The method of claim 17 wherein the alpha-fluoroacrylic acid polymer is crossliniked with divinylbenzene, ethylene bisacrylamide, N,N'-bis(vinylsulfonylacetyl) ethylene diamine, 1,3-bis(vinylsulfonyl) 2-propanol, vinylsulfone, N,N'-methylenebisacrylamide polyvinyl ether, polyallylether, or a combination thereof. 19. The method of claim 17 wherein the potassium-binding polymer is in a bead form.