Claims for Patent: 6,890,957

Summary for Patent: 6,890,957

Title:	Liquid formulation of metformin
Abstract:	The present invention is directed to a liquid formulation of metformin or its pharmaceutically acceptable salts thereof. The liquid pharmaceutical composition comprises a therapeutically effective amount of metformin or its pharmaceutically acceptable salt, in a liquid carrier, which may also include a sweetener that does not increase the blood glucose level of a subject after ingestion thereof. In one embodiment, it may also include alkyl hydroxyethylcellulose, and/or a polyhydroxy alcohol. In another embodiment, the carrier may contain a sweetener, mineral acid, and bicarbonate salt maintained at a pH of 4.0 to 9.0. It is useful for treating hyperglycemia and diabetes.
Inventor(s):	Chandran; Ravi (Bolton Landing, NY), Gogia; Ashish (New Delhi, IN)
Assignee:	Ranbaxy Laboratories Limited (New Delhi, IN)
Application Number:	10/382,442
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 6,890,957
Patent Claims:	1. A liquid pharmaceutical composition for oral administration which comprises a therapeutically effective amount of metformin or its pharmaceutically acceptable salt; a sweetener that does not increase the blood glucose level of a subject after ingestion thereof; a polyhydroxy alcohol present in an amount of about 15 to about 55% by weight; a mineral acid and bicarbonate salt both present in sufficient amounts to maintain the pH of the composition in the range of about 4.0 to about 9.0; and a pharmaceutically acceptable liquid carrier. 2. The liquid pharmaceutical composition according to claim 1, where the pharmaceutically acceptable carrier is water. 3. The pharmaceutical composition of claim 1 wherein the sweetener is present in amounts ranging from about 50% to about 70% by weight. 4. The liquid pharmaceutical composition of claim 3, wherein the sweetener is present in amounts ranging from about 55% to about 65% by weight. 5. The liquid pharmaceutical composition of claim 1, further comprising alkyl hydroxyethylcellulose. 6. The liquid pharmaceutical composition of claim 5, wherein the alkyl hydroxyethylcellulose is present in amounts ranging from 0.08% to about 0.2% by weight. 7. The liquid pharmaceutical composition of claim 1, wherein the polyhydroxy alcohol is present in amounts ranging from about 15% to about 40% by weight. 8. The liquid pharmaceutical composition of claim 5, wherein the alkyl group in alkyl hydroxyethylcellulose contains 2 to 10 carbon atoms. 9. The liquid pharmaceutical composition of claim 1, wherein the sweetener is a sugar alcohol or non-nutritive sweetener. 10. The liquid pharmaceutical composition of claim 1, wherein the polyhydroxy alcohol contains 2 to 6 carbon atoms and contains 2 to 6 hydroxy groups. 11. The liquid pharmaceutical composition of claim 1, wherein the polyhydroxy alcohol is a polymer having a molecular weight ranging from 200 to 2000 daltons and has a repeating unit of 2 to 6 carbon atoms and the repeating unit contains 2 to 6 hydroxy groups. 12. The liquid pharmaceutical composition according to claim 1 wherein the mineral acid is hydrochloric acid, nitric acid, or sulfuric acid. 13. The liquid pharmaceutical composition according to claim 12 herein the mineral acid is hydrochloric acid. 14. The liquid pharmaceutical composition according to claim 1 herein the pH ranges from about 4.2 to about 7.0. 15. The liquid pharmaceutical composition according to claim 1 wherein the bicarbonate salt is potassium bicarbonate.