Details for Patent: 7,381,428

Title:	Stabilized lanthanum carbonate compositions
Abstract:	Stabilized lanthanum carbonate compositions containing a monosaccharide or disaccharide stabilizing agent are disclosed. Subjects having hyperphosphatemia can be treated by administering a pharmaceutical composition containing a therapeutically effective amount of the stabilized lanthanum carbonate formulation.
Inventor(s):	Ferdinando; Josephine Christine (Tadley, GB), Davies; Peter Neil (Basingstoke, GB)
Assignee:	Shire International Licensing B.V. (NL)
Filing Date:	Nov 09, 2005
Application Number:	11/272,569
Claims:	1. In a method for treating hyperphosphatemia comprising administering a therapeutically effective amount of a lanthanum carbonate composition comprising lanthanum carbonate having the formula: La.sub.2(CO.sub.3).sub.3.xH.sub.2O wherein x has a value from 0 to 10, in an amount effective to treat hyperphosphatemia, the improvement comprising: stabilizing the lanthanum carbonate against substantial decarboxylation to lanthanum hydroxycarbonate before administration by admixing the lanthanum carbonate in an amount of from 13.4-13.9% to 32.2-33.3% by weight of the composition as elemental lanthanum with a monosaccharide or disaccharide in an amount from 20 to 80% by weight of the composition, wherein the monosaccharide or disaccharide is dextrates, mannitol, sorbitol, or a mixture thereof and the amount of the monosaccharide or disaccharide is such that lanthanum hydroxycarbonate is not observed in an x-ray powder diffraction (XRPD) pattern of the lanthanum carbonate composition after it has been exposed to 60.degree. C. and 95% relative humidity for at least 7 days. 2. The method of claim 1, wherein the monosaccharide or disaccharide is dextrates. 3. The method of claim 1, wherein the monosaccharide or disaccharide is sorbitol. 4. The method of claim 1, wherein the stabilized composition comprises 26.5% by weight lanthanum carbonate, 69.3% by weight dextrates, 2% by weight colloidal silicon dioxide, 1.7% by weight talc, and 0.5% by weight magnesium stearate, and wherein the lanthanum carbonate has a water content approximately equivalent to 4-5 moles of water. 5. The method of claim 1, wherein the stabilized composition comprises 63.6% by weight lanthanum carbonate, 2% by weight colloidal silicon dioxide, 1% by weight talc, 30.4% by weight sorbitol, and 3.0% by weight glyceryl dibehenate, and wherein the lanthanum carbonate has a water content approximately equivalent to 4-5 moles of water. 6. The method of claim 1, wherein the stabilized composition comprises 45.8% by weight lanthanum carbonate, 51.1% by weight dextrates, 2.1% by weight colloidal silicon dioxide, and 1.0% by weight magnesium stearate, and wherein the lanthanum carbonate has a water content approximately equivalent to 4-5 moles of water. 7. A method for stabilizing a lanthanum carbonate pharmaceutical composition for treating hyperphosphatemia, the lanthanum carbonate having the formula: La.sub.2(CO.sub.3).sub.3.xH.sub.2O wherein x has a value from 0 to 10, and the lanthanum carbonate being stabilized against substantial decarboxylation to lanthanum hydroxycarbonate comprising: admixing the lanthanum carbonate in an amount of from 13.4-13.9% to 32.2-33.3% by weight of the composition as elemental lanthanum with a monosaccharide or disaccharide in an amount from 20 to 80% by weight of the composition, wherein the monosaccharide or disaccharide is dextrates, mannitol, sorbitol, or a mixture thereof and the amount of the monosaccharide or disaccharide is such that lanthanum hydroxycarbonate is not observed in an x-ray powder diffraction (XRPD) pattern of the lanthanum carbonate composition after it has been exposed to 60.degree. C. and 95% relative humidity for at least 7 days. 8. The method of claim 7, wherein the monosaccharide or disaccharide is dextrates. 9. The method of claim 7, wherein the monosaccharide or disaccharide is sorbitol. 10. The method of claim 7, wherein the stabilized composition comprises 26.5% by weight lanthanum carbonate, 69.3% by weight dextrates, 2% by weight colloidal silicon dioxide, 1.7% by weight talc, and 0.5% by weight magnesium stearate, and wherein the lanthanum carbonate has a water content approximately equivalent to 4-5 moles of water. 11. The method of claim 7, wherein the stabilized composition comprises 63.6% by weight lanthanum carbonate, 2% by weight colloidal silicon dioxide, 1% by weight talc, 30.4% by weight sorbitol, and 3.0% by weight glyceryl dibehenate, and wherein the lanthanum carbonate has a water content approximately equivalent to 4-5 moles of water. 12. The method of claim 7, wherein the stabilized composition comprises 45.8% by weight lanthanum carbonate, 51.1% by weight dextrates, 2.1% by weight colloidal silicon dioxide, and 1.0% by weight magnesium stearate, and wherein the lanthanum carbonate is hydrated having a water content approximately equivalent to 4-5 moles of water.