Claims for Patent: 5,900,424

Summary for Patent: 5,900,424

Title:	Omeprazole magnesium salt form
Abstract:	A novel compound form of magnesium omeprazole useful in the manufacture of pharmaceutical formulations, the use of the product and the process for its production are described.
Inventor(s):	Kallstrom; Lars .ANG.ke (Sodertalje, SE), Nygren; Monica Annelie (Sodertalje, SE)
Assignee:	Astra Aktiebolag (Sodertalje, SE)
Application Number:	08/313,342
Patent Claims:	1. An omeprazole magnesium salt having a degree of crystallinity which is higher than 70% as determined by x-ray powder diffraction. 2. The omeprazole magnesium salt according to claim 1 wherein the degree of crystallinity is higher than 75%. 3. The omeprazole magnesium salt according to claim 1 wherein the mean particle diameter as determined by laser diffraction technique is less than 30 .mu.m, and preferably less than 20 .mu.m. 4. The omeprazole magnesium salt according to claim 1 wherein the density is between 1.33 g/cm.sup.3 and 1.35 g/cm.sup.3 as determined by powder pycnometer. 5. The omeprazole magnesium salt according to claim 1 wherein the water content is between 5% and 10% by weight as determined by titration according to Karl Fischer. 6. The omeprazole magnesium salt according to claim 1 having a solvent content less than 0.1% by weight of solvent as determined by gas chromatography. 7. The omeprazole magnesium salt according to claim 1 having a solvent content less than 0.05% by weight of solvent as determined by gas chromatography. 8. The omeprazole magnesium salt of claim 6 or 7, wherein the solvent is an aqueous alcohol. 9. The omeprazole magnesium salt of claim 6 or 7, wherein the solvent is methanol. 10. The omeprazole magnesium salt according to claim 1 wherein the hygroscopicity is less than 2% increase of weight upon storage for one month at up to 94% relative atmospheric humidity as determined by gravimetry. 11. A process for the manufacture of magnesium omeprazole according to claim 1 comprising in consecutive steps a) treating omeprazole or salt thereof with magnesium alcoholate in a solution, b) separating inorganic salts from the reaction mixture, c) crystallizing magnesium omeprazole by the addition of water, and d) isolating the obtained crystalline magnesium omeprazole. 12. A process according to claim 11 wherein the magnesium alcoholate is magnesium methyl alcoholate. 13. A process according to claim 11 wherein the solvent is methanol. 14. A process according to claim 11 wherein the isolation of the magnesium omeprazole is performed by centrifugal separation of the crystals. 15. A process according to claim 11 wherein the isolation of the magnesium omeprazole is performed by crystallization followed by filtration of the crystals. 16. The process according to claim 11, further comprising the steps of purifying and drying the crystalline magnesium omeprazole. 17. A process according to claim 16 wherein the purification of the magnesium omeprazole crystals is performed by washing the crystals with a solution of polar solvents. 18. A process according to claim 16 wherein the magnesium omeprazole crystals are dried under reduced pressure. 19. A process according to claim 16 wherein the drying of the magnesium omeprazole crystals is performed by evaporating the remaining solvent by heating. 20. In a process for the manufacture of a crystalline magnesium salt comprising, (a) treating omeprazole or a salt thereof with magnesium alcoholate in a solution, (b) crystallizing magnesium omeprazole and (c) isolating the obtained crystalline magnesium omeprazole, wherein the improved process comprises separating inorganic salts from the reaction mixture prior to the crystallization step by the addition of water. 21. A method for inhibiting gastric acid secretion in mammals and man comprising administering to a host in need thereof a therapeutically effective dose of magnesium omeprazole according to any of claims 1 to 4, 6-8 and 10. 22. A method for the treatment of gastric acid related diseases in mammals and man comprising administering to a host in need thereof a therapeutically effective dose of magnesium omeprazole according to any of claims 1 to 4, 6-8 and 10.