Claims for Patent: 4,335,139

Summary for Patent: 4,335,139

Title:	Pharmaceutical formulations containing prostacyclin compounds
Abstract:	Stabilized pharmaceutical formulations of prostacyclin or certain analogues thereof comprising an amino acid buffer, optionally containing a base, and the preparation of such formulations.
Inventor(s):	Watts; Ian S. (Sidcup, GB2), Marsden; Peter H. (Dartford, GB2)
Assignee:	Burroughs Wellcome Co. (Research Triangle Park, NC)
Application Number:	06/182,054
Patent Claims:	1. A pharmaceutical formulation comprising an active compound selected from prostacyclin, 15-methylprostacyclin, 16, 16-dimethylprostacyclin or a pharmaceutically acceptable salt of any one of these in association with a pharmaceutically acceptable buffer having a pH of at least 9 and based on a pharmaceutically acceptable amino acid as a buffering acid in the buffer and, optionally, a further pharmaceutically acceptable carrier. 2. A formulation according to claim 1, wherein the further pharmaceutically acceptable carrier is or includes a solvent which dissolves the active compound and the buffer, to form a solution. 3. A formulation according to claim 1, wherein the further pharmaceutically acceptable carrier is or includes water. 4. A formulation according to claim 1, wherein a solution containing the active compound and the buffer is suitable for injection or infusion. 5. A formulation according to claim 1, wherein a solution containing the active compound and the buffer is freeze dried or frozen. 6. A formulation according to claim 1, wherein the amino-acid is sulphur-free. 7. A formulation according to claim 1, wherein the amino-acid is selected from the group consisting of glycine, alanine, arginine and valine. 8. A formulation according to claim 1, wherein the total concentration of the amino-acid including its salts, is in the range of from 0.02 to 0.03 M. 9. A formulation according to claim 1, wherein the total concentration of the amino-acid, including its salts, is about 0.025 M. 10. A formulation according to claim 1, wherein the further pharmecutically acceptable carrier comprises sodium chloride. 11. A formulation according to claim 1, wherein the pH of the buffer is in the range of from 10.2 to 10.8. 12. A formulation according to claim 1, wherein the further pharmaceutically acceptable carrier comprises an excipient. 13. A formulation according to claim 1, wherein the further pharmaceutically acceptable carrier comprises mannitol. 14. A formulation according to claim 1, wherein the active compound is prostacyclin or a salt thereof. 15. A formulation according to claim 1, wherein the salt is a sodium salt. 16. A formulation according to claim 1, wherein the active compound is prostacyclin sodium salt. 17. A formulation according to claim 1, comprising prostacyclin sodium salt in association with glycine and optionally, a further pharmaceutically acceptable carrier. 18. A method of preparing a pharmaceutical formulation according to claim 1, which comprises bringing an active compound selected from prostacyclin, 15-methylprostacyclin, 16,16-dimethylprostacyclin, and a salt of any one of these into association with a pharmaceutically acceptable buffer having a pH of at least 9 and based on an amino-acid as principal buffering acid in the buffer and, optionally, a further pharmaceutically acceptable carrier. 19. A formulation according to claim 1, when prepared by a method according to claim 18. 20. A method of inhibiting the aggregation of platelets, which comprises the bringing of said platelets into association with an amount of a formulation according to claim 1 containing an effective platelet aggregation inhibitory amount of the active compound. 21. A method of inducing vasodilation in a mammal, which comprises the administration to said mammal of an amount of a formulation according to claim 1 containing a non-toxic, effective vasodilatory amount of the active compound. 22. A method for the treatment or prophylaxis of thrombosis in a mammal or mammalian tissue which comprises administration of an amount of a formulation according to claim 1 containing a non-toxic, effective antithrombotic amount of the active compound. 23. A method of lowering blood pressure in a mammal which comprises administration to said mammal of an amount of a formulation according to claim 1 containing a non-toxic, effective hypotensive amount of the active compound. 24. A method for the treatment or prophylaxis of a gastric lesion in a mammal which comprises administration to said mammal of an amount of a formulation according to claim 1 containing a non-toxic, effective therapeutic or prophylactic amount of the active compound. 25. A method of stabilizing an active compound selected from the group consisting of prostacyclin, 15-methylprostacyclin, 16,16-dimethylprostacyclin and a pharmaceutically acceptable salt of any one of these against hydrolysis of the enol ether moiety, which method comprises bringing said compound selected from the group consisting of prostacyclin, 15-methylprostacyclin, 16,16-dimethylprostacyclin, and a pharmaceutically acceptable salt thereof into association with a pharmaceutically acceptable buffer having a pH of at least 9 and based on an amino acid as a buffering acid in the buffer. 26. A pharmaceutical formulation comprising an active compound selected from prostacyclin, 15-methylprostacyclin, 16,16-dimethylprostacyclin and a salt of any one of these in association with a pharmaceutically acceptable buffer based on an amino acid as principal buffering agent and buffered to a pH of at least 9. 27. A formulation according to claim 26, wherein the formulation further includes a base. 28. A pharmaceutical composition comprising prostacyclin or a pharmaceutically acceptable salt thereof in association with a pharmaceutically acceptable buffer having a pH of at least 9 and based on an amino acid as the principal buffering acid in the buffer. 29. The composition of claim 28 in which the amino acid is arginine. 30. The composition of claim 28 in which the amino acid is valine. 31. The composition of claim 28 in which the amino acid is alanine. 32. The composition of claim 28 in a form for injection, said composition including water. 33. A pharmaceutical composition comprising the sodium salt of prostacyclin in association with a pharmaceutically acceptable buffer having a pH of at least 9 and based on glycine as the acid in the buffer. 34. The composition of claim 33 in a form for injection, said composition including water.