COMPOUND COMPRISING CRYSTALLINE LANTHANUM OXYCARBONATE, METHOD OF MAKING LANTHANUM OXYCARBONATE, USE THEREOF FOR TREATING HYPERPHOSPHATEMIA

摘要

The present invention relates to rare earth metal compounds, having a porous structure. A composition is disclosed comprising a compound of crystalline lanthanum oxycarbonate with a BET specific surface area of about 19 m²/g and exhibiting a phosphate binding of at least 40% of the initial phosphate content after 10 min at pH of about 3 A method is disclosed of treating hyperphosphatemia in a mammal comprising administering an effective amount of said composition. Besides, the invention relates to a method of producing a lanthanum oxycarbonate comprising: a) reacting a lanthanum chloride with a carbonate at a temperature of 30 to 90°, forming precipitation; b) recovering the resulting precipitate producing lanthanum oxycarbonate having a BET specific surface area of at least about 10 m²/g; and c) thermally treating the precipitate at a temperature of 400 to 700° to produce an anhydrous lanthanum oxycarbonate selected from anhydrous crystalline La₂O₂CO₃ and anhydrous crystalline La₂CO₅.