Claims for Patent: 5,358,970

Summary for Patent: 5,358,970

Title:	Pharmaceutical composition containing bupropion hydrochloride and a stabilizer
Abstract:	This application discloses a method of inhibiting degradation of the antidepressant bupropion hydrochloride in a solid pharmaceutical formulation, so that the pharmaceutical formulation will maintain at least 80% of its initial bupropion potency after one year.
Inventor(s):	Ruff; Michael D. (Greenville, NC), Kalidindi; Sanyasi R. (Edison, NJ), Sutton, Jr.; Joel E. (Greenville, NC)
Assignee:	Burroughs Wellcome Co. (Research Triangle Park, NC)
Application Number:	08/105,437
Patent Claims:	1. A pharmaceutical composition in solid form comprising bupropion hydrochloride and a pharmaceutically acceptable stabilizer in an effective stabilizing amount and which is solid or liquid at 30.degree. C. wherein said stabilizer has a aqueous solution pH of about 0.9 to about 4 at an aqueous solution concentration of about 6% w/w, and said composition, when stored for 6 weeks at about 50 degrees C. and at about 27% relative humidity contains at least about 80% of the labelled amount of bupropion hydrochloride in the composition, said stabilizer selected from the group consisting of L-cysteine hydrochloride, glycine hydrochloride, malic acid, sodium metabisulfate, citric acid, tartaric acid and L-cysteine dehydrochloride. 2. The composition of claim 1 in the form of a tablet or a capsule comprising bupropion hydrochloride and inactive ingredients wherein the weight of bupropion hydrochloride in the tablet or capsule is Y and the amount of inactive ingredients is greater than about 50% of Y and less than about 400% of Y. 3. The tablet of claim 2 in which the amount of bupropion hydrochloride in the tablet or capsule is 25 to 500 mg. 4. The tablet or capsule of claim 2 in which the amount of bupropion hydrochloride in the tablet is 50, 75, 100 or 150 mg. 5. The composition of claim 1 in the form of a tablet containing 25 to 300 mg of bupropion hydrochloride. 6. The composition of claims 1, 2, 3, 4, or 8 in which the amount of the stabilizer is 2.7% to 27% of the weight of bupropion hydrochloride in the composition. 7. The composition of claims 1, 2, 3, 4, or 8 in which the amount of stabilizer is 5% to 16.2% of the weight of bupropion hydrochloride in the composition. 8. A method of inhibiting degradation of bupropion hydrochloride in a tablet or capsule which comprises mixing bupropion hydrochloride with a stabilizer, having an aqueous solution pH between about 0.9 to 4 at an aqueous solution concentration of 6% w/w, in an amount of about 2.7% to about 27% of the weight of bupropion hydrochloride to form a solid form of the mixture in the form of a tablet or capsule, said tablet or capsule maintaining at least 80% of its initial potency after storage for six weeks at about 50.degree. C. at about 27% humidity. 9. The method of claim 8 in which said amount of stabilizer is about 5% to about 16.2%. 10. The method of claim 7 or 8 in which the stabilizer is cysteine hydrochloride in the L form. 11. The method of claim 7 or 8 in which the stabilizer is glycine hydrochloride. 12. The composition of claim 1 in which the stabilizer is L-cystsine hydrochloride. 13. The composition of claim 2 in which the stabilizer is L-cystsine hydrochloride. 14. The composition of claim 3 in which the stabilizer is L-cystsine hydrochloride. 15. The composition of claim 4 in which the stabilizer is L-cystsine hydrochloride. 16. The composition of claim 14 in which the amount of stabilizer is 2.7% to 27% of the weight of bupropion hydrochloride in the composition. 17. The composition of claim 16 in which the amount of stabilizer is 5% to 16.2 of the weight of bupropion hydrochloride in the composition.