Process for preparing oral calcium compositions

1. A process for the preparation of an orally administrable calcium composition, said process comprising the steps of:

(i) obtaining a physiologically tolerable particulate calcium compound having a mean particle size in the range 3 to 40 μm, having a crystalline structure and having a surface area of 0.1 to 1.2 m 2 /g;

(ii) mixing said calcium compound with a water-soluble diluent and an aqueous solution of a water soluble binder in a fluid bed granulation apparatus and drying the resulting mixture to produce a first granulate;

(iii) mixing said first granulate with one or more further components to produce a second granulate; and

(iv) compressing said first or second granulate to form tablets having a porosity of from 25-30%.

2. A process as claimed in claim 1 wherein said calcium compound is selected from the group consisting of calcium carbonate, calcium lactate, calcium gluconate, calcium citrate, calcium glycerophosphate, calcium phosphate, calcium hydrogen phosphate, calcium glucuronate, calcium aspartate, calcium glucoheptonate and mixtures of two or more thereof.

3. A process as claimed in claim 1 wherein said calcium compound is calcium carbonate.

4. A process as claimed in claim 1 wherein said calcium compound makes up 68 to 80% wt. of said first granulate.

5. A process as claimed in claim 1 wherein said calcium compound makes up 60 to 95% wt. of said second granulate.

6. A process as claimed in claim 1 wherein in step (i) the same material is used as said diluent and as said binder.

7. A process as claimed in claim 1 wherein said water-soluble diluent comprises at least one sweetener.

8. A process as claimed in claim 7 wherein said sweetener is selected from the group consisting of sorbitol, xylitol, isomalt, mannitol, sucrose, fructose, maltodextrin, inulin and oligofructose.

9. A process as claimed in claim 1 wherein said water-soluble diluent makes up 70 to 96% wt. of the total weight of said water-soluble diluent and said water-soluble binder in said first granulate.

10. A process as claimed in claim 1 wherein said water-soluble binder is selected from the group consisting of celluloses, polysaccharides, maltodextrin, inulin and polyvinylpyrrolidone.

11. A process as claimed in claim 1 wherein said water-soluble binder is a polyvinylpyrrolidone.

12. A process as claimed in claim 1 wherein said first granulate has a particle size distribution of 0 (V, 0.1)=15-21 μm, D (V, 0.5)=70-120 μm and D (V, 0.9)=190-330 μm.

13. A process as claimed in claim 1 wherein a said further component is mixed with said first granulate, said further component being selected from the group consisting of vitamin B 6 , vitamin K, vitamin C, vitamin D, isoflavones, inulin, and oligofructose and mixtures of two or more thereof.

14. A process as claimed in claim 1 wherein in step (ii) said calcium compound is also mixed with isoflavones.

15. A tablet comprising a compressed granulate comprising a fluid bed granulation granulate product of a physiologically tolerable calcium compound, a water-soluble binder and a water-soluble diluent, said calcium compound having a mean particle size in the range 3 to 40 μm, having a crystalline structure and having a surface area of 0.1 to 1.2 m 2 /g, and containing: calcium carbonate; vitamin D 3 ; a lubricant; citric acid; and an oligosaccharide, said tablet having a porosity of from 25-30% and having a dissolution rate where 90% of the elemental calcium is dissolved within 10 minutes.

16. A process as claimed in claim 1 , wherein the tablets have a dissolution rate where 90% of the elemental calcium is dissolved within 10 minutes.