Phosphorous binder for treatment of kidney disease

Abstract

The present invention relates to oral compositions which are useful for binding phosphorus in ingesta, and inhibiting absorption of phosphorus from the gastrointestinal tract of subjects. A method for binding phosphorus in ingesta and inhibiting its absorption from the gastrointestinal tract is also provided. The dietary supplements and pharmaceutical products and methods of the present invention are particularly useful in the treatment of hyperphosphatemia of chronic uremia and reducing serum phosphorus levels in patients requiring such therapy.

1 . A composition for reducing the amount of dietary phosphorus absorbed from the alimentary tract comprising a cationic phosphate binder; and a dithiolane carboxylate salt. 
     
     
         2 . The composition of  claim 1  wherein the cationic phosphate binder is a calcium salt selected from the group consisting of calcium acetate, calcium carbonate, calcium citrate, calcium alginate, calcium gluconate, calcium lactate, calcium sulfate, and calcium succinate, and combinations thereof. 
     
     
         3 . The composition of  claim 1  wherein the dithiolane carboxylate salt has the structure 
       
         
           
           
               
               
           
         
         wherein M is a cation of valence 2 and n is an integer from 1-8. 
       
     
     
         4 . The composition of  claim 1  wherein the cationic phosphate binder is a lanthanum salt. 
     
     
         5 . The composition of  claim 1  wherein the cationic phosphate binder is a cationic polymer. 
     
     
         6 . The composition of  claim 1  wherein the cationic phosphate binder is a relative hydrophile selected from the group consisting of calcium acetate, calcium gluconate, calcium lactate, and calcium succinate, and the dithiolane carboxylate salt is a relative lipophile selected from the group consisting of compounds of structure 
       
         
           
           
               
               
           
         
         wherein M is a cation of valence 2 and n is an integer from 4-8. 
       
     
     
         7 . The composition of  claim 6  wherein the cation of valence 2 is Ca ++, Mg   ++ , lanthanum, or a combination thereof. 
     
     
         8 . A composition for reducing the amount of dietary phosphorus absorbed in the alimentary tract comprising a cationic phosphate binder and a dithiolane carboxylate salt, wherein the cationic phosphate binder is a calcium salt is selected from the group consisting of calcium acetate, calcium carbonate, calcium citrate, calcium alginate, calcium gluconate, calcium lactate, calcium sulfate, and calcium succinate, and combinations thereof, and the dithiolane carboxylate salt is magnesium lipoate. 
     
     
         9 . The composition of  claim 8  wherein the said calcium salt and said dithiolane carboxylic acid salt are administered orally in a ratio of about 6:0.1 to about 1:6 by molar weight. 
     
     
         10 . A composition for reducing the amount of dietary phosphorus absorbed from the alimentary tract comprising a cationic phosphate binder and a dithiolane carboxylate salt, wherein the cationic phosphate binder is a lanthanum salt and the dithiolane carboxylate salt is magnesium lipoate. 
     
     
         11 . A composition for reducing the amount of dietary phosphorus absorbed in the alimentary tract comprising a cationic phosphate binder and a dithiolane carboxylate salt, wherein the cationic phosphate binder is a cationic polymer and the dithiolane carboxylate salt is magnesium lipoate. 
     
     
         12 . A method for inhibiting absorption of dietary phosphorus from the alimentary tract of a mammal comprising orally ingesting a composition comprising a cationic phosphate binder and a dithiolane carboxylate salt in sufficient dose to control, abate, ameliorate, or prevent hyperphosphatemia or its associated pathologies. 
     
     
         13 . The method of  claim 12  wherein oral administration is by ingestion with food or by ingestion close in time to the consumption of dietary phosphate-containing food or beverage by a mammal. 
     
     
         14 . The method of  claim 13  wherein administration of the composition of  claim 1  is a food additive within the meaning of title 21 of the CFR (Code of Federal Regulations) or a drug within the meaning of title 21 of the CFR (Code of Federal Regulations).