Claims for Patent: 5,030,447

Summary for Patent: 5,030,447

Title:	Pharmaceutical compositions having good stability
Abstract:	A pharmaceutical compositions is provided which has excellent stability, when dispersed in water has a pH of at least about 9, and includes a medicament which is sensitive to a low pH environment such as pravastatin, one or more fillers such as lactose and/or microcrystalline cellulose, one or more binders, such as mirocrystalline cellulose (dry binder) or polyvinylpyrrolidone (wet binder), one or more disintegrating agents such as croscarmellose sodium, one or more lubricants such as magnesium stearate and one or more basifying agents such as magnesium oxide.
Inventor(s):	Joshi; Yatindra M. (Piscataway, NJ), Chiesa; Pierina (South Orange, NJ), Jain; Nemichand B. (Monmouth Junction, NJ)
Assignee:	E. R. Squibb & Sons, Inc. (Princeton, NJ)
Application Number:	07/176,127
Patent Claims:	1. A pharmaceutical composition in the form of a tablet which has enhanced stability comprising medicament which is sensitive to a low pH environment and is pravastatin, one of more fillers, one or more binders, one or more disintegrants, one of more lubricants and one or more basifying agents to impart a desired pH of at least 9 to an aqueous dispersion of said composition. 2. The pharmaceutical composition as defined in claim 1 wherein said medicament is present in an amount within the range of from about 1 to about 60% by weight of the composition. 3. The pharmaceutical composition as defined in claim 1 wherein the basifying agent is present in an amount within the range of from about 1 to about 75% by weight of the composition. 4. The pharmaceutical composition as defined in claim 1 wherein the basifying agent is an alkali metal hydroxide, an alkaline earth metal hydroxide or ammonium hydroxide. 5. The pharmaceutical composition as defined in claim 5 wherein the basifying agent is MgO, Mg(OH).sub.2, Ca(OH).sub.2, NaOH, KOH, LiOH, NH.sub.4 OH, Al(OH).sub.3 or magaldrate. 6. The pharmaceutical composition as defined in claim 1 wherein the filler is present in an amount within the range of from about 5 to about 90% by weight. 7. The pharmaceutical composition as defined in claim 6 wherein the filler is lactose, sugar, corn starch, modified corn starch, mannitol, sorbitol, wood cellulose, microcrystalline cellulose, calcium carbonate or mixtures thereof. 8. The pharmaceutical composition as defined in claim 1 wherein the binder is present in an amount within the range of from about 5 to about 35% by weight. 9. The pharmaceutical composition as defined in claim 8 wherein the binder is microcrystalline cellulose, polyvinylpyrrolidone, lactose, corn starch, modified corn starch, sugars, gum acacia, carnauba wax, paraffin, spermaceti, polyethylenes or microcrystalline wax. 10. The pharmaceutical composition as defined in claim 1 wherein the disintegrant is present in an amount within the range of from about 0.5 to about 10% by weight. 11. The pharmaceutical composition as defined in claim 10 wherein the disintegrant is croscarmellose sodium, crospovidone, sodium starch glycolate, corn starch or microcrystalline cellulose. 12. The pharmaceutical composition as defined in claim 1 having the following formulation: from about 3 to about 50% by weight pravastatin, from about 2 to about 70% by weight magnesium oxide, to impart a pH of at least about 9.5, from about 1 to about 85% by weight lactose, from about 10 to about 30% by weight microcrystalline cellulose or polyvinylpyrrolidone, from about 2 to about 8% by weight of croscarmellose sodium; and from about 0.5 to about 2% by weight magnesium stearate. 13. The pharmaceutical composition as defined in claim 1 having a pH in water of at about 10.