Claims for Patent: 7,094,427

Summary for Patent: 7,094,427

Title:	Combination immediate release controlled release levodopa/carbidopa dosage forms
Abstract:	The present invention relates to dosage forms of a combination of carbidopa and levodopa comprising both immediate release and controlled release components for the treatment of ailments associated with depleted amounts of dopamine in a patient's brain tissue.
Inventor(s):	Han; Chien-Hsuan (Sunnyvale, CA), Hsu; Larry (Los Altos Hills, CA), Hsu; Ann F. (Los Altos Hills, CA)
Assignee:	Impax Laboratories, Inc. (Hayward, CA)
Application Number:	10/241,837
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 7,094,427
Patent Claims:	1. A pharmaceutical dosage form having an immediate release component and a controlled release component comprising: a) an immediate release component comprising a ratio of carbidopa to levodopa of from about 1:1 to about 1:50 such that the in vitro dissolution rate of the immediate release component according to measurements under the USP paddle method of 50 rpm in 900 ml aqueous buffer at pH 4 at 37.degree. C. is from about 10% to about 99% levodopa released after 15 minutes and from about 60% to about 99% after 1 hour; and b) a controlled release component comprising a ratio of carbidopa to levodopa of from about 1:1 to about 1:50 such that the in vitro dissolution rate of the controlled release component according to measurements under the USP paddle method of 50 rpm in 900 ml aqueous buffer at pH 4 at 37.degree. C. is from about 10% to about 60% levodopa released after 1 hour; from about 20% to about 80% levodopa eased after 2 hours; and from about 30% to about 99% levodopa released after about 6 hours, the in vitro release rate chosen such that the initial peak plasma level of levodopa obtained in vivo occurs between 0.1 and 6 hours after administration of the dosage form to a patient. 2. A pharmaceutical dosage form according to claim 1 wherein said immediate release component comprises a ratio of carbidopa to levodopa of from about 1:1 to about 1:50 such that the in vitro dissolution rate of the immediate release component according to measurements under the USP paddle method of 50 rpm in 900 ml aqueous buffer at ph 4 at 37.degree. C. is from about 10% to about 99% levodopa released after 15 minutes and from about 75% to about 99% after 1 hour; and said controlled release component comprises a ratio of carbidopa to levodopa of from about 1:1 to about 1:50 such that the in vitro dissolution rate of the controlled release component according to measurements under the USP paddle method of 50 rpm in 900 ml aqueous buffer at pH 4 at 37.degree. C. is from about 10% to about 60% levodopa released after 1 hour; from about 25% to about 80% levodopa released after 2 hours; from about 30% to about 85% levodopa released after 4 hours; and from about 40% to about 99% levodopa released after about 6 hours, the in vitro release rate chosen such that the initial peak plasma level of levodopa obtained in vivo occurs between 0.1 and 6 hours after administration of the dosage form to a patient. 3. A pharmaceutical dosage form according to claim 2 wherein the immediate release component comprises a ratio of carbidopa to levodopa of from about 1:1 to about 1:10. 4. A pharmaceutical dosage form according to claim 2 wherein the immediate release component comprises a ratio of carbidopa to levodopa of from about 1:1 to about 1:5. 5. A pharmaceutical dosage form according to claim 2 wherein the immediate release component comprises a ratio of carbidopa to levodopa of from about 1:1 to about 1:4. 6. A pharmaceutical dosage form according to claim 2 wherein the controlled release component comprises a ratio of carbidopa to levodopa of from about 1:1 to about 1:10. 7. A pharmaceutical dosage form according to claim 2 wherein the controlled release component comprises a ratio of carbidopa to levodopa of from about 1:1 to about 1:5. 8. A pharmaceutical dosage form according to claim 2 wherein the controlled release component comprises a ratio of carbidopa to levodopa of from about 1:1 to about 1:4. 9. A pharmaceutical dosage form according to claim 2 wherein the in vitro dissolution rate of carbidopa of the immediate release component according to measurements under the USP paddle method of 50 rpm in 900 ml aqueous buffer at pH 4 at 37.degree. C. is from about 95% to about 99% after about 1 hour. 10. A pharmaceutical dosage form according to claim 2 wherein the controlled release component comprises from about 10 to about 200 mg of carbidopa and from 25 to about 600 mg levodopa. 11. A pharmaceutical dosage form according to claim 2 wherein the controlled release component comprises from about 25 to about 150 mg of carbidopa and from 50 to about 500 mg levodopa. 12. A pharmaceutical dosage form according to claim 2 wherein the controlled release component comprises from about 25 to about 50 mg of carbidopa and from 50 to about 200 mg levodopa. 13. A pharmaceutical dosage form according to claim 2 wherein the immediate release component comprises from about 5 to about 75 mg of carbidopa and from 25 to about 300 mg levodopa. 14. A pharmaceutical dosage form according to claim 2 wherein a percentage of the total amount of carbidopa is replaced by another decarboxylase inhibitor. 15. A pharmaceutical dosage form according to claim 2 wherein some or all of the levodopa is in the form of the pro-drug 3-hydroxy-L-tyrosine ethyl ester. 16. A pharmaceutical dosage form according to claim 2 wherein the dosage form is comprised of particles. 17. A pharmaceutical dosage form according to claim 1 wherein the dosage form is comprised of a tablet. 18. A pharmaceutical dosage form according to claim 2 wherein the dosage form is comprised of a bilayer tablet. 19. A pharmaceutical dosage form according to claim 2 wherein the amount of carbidopa in the dosage form is selected from the group consisting of 12.5, 25, 50, 75 and 100 mg. 20. A pharmaceutical dosage form according to claim 2 wherein the amount of levodopa in the dosage form is selected from the group consisting of 25, 37.5, 50, 70, 75, 80, 100, 125, 130, 150, 200, 250, 300, and 400 mg. 21. A pharmaceutical dosage form according to claim 2 wherein the total amount of carbidopa to levodopa in the dosage form is 50 mg/100 mg with the carbidopa to levodopa amount in the immediate release portion being 25 mg/50 mg and the carbidopa to levodopa amount in the controlled release portion being 25 mg/50 mg. 22. A pharmaceutical dosage form according to claim 2 wherein the total amount of carbidopa to levodopa in the dosage form is 50mg/150 mg with the carbidopa to levodopa amount in the immediate release portion being 25 mg/70 mg and the carbidopa to levodopa amount in the controlled release portion being 25 mg/80 mg. 23. A pharmaceutical dosage form according to claim 2 wherein the total amount of carbidopa to levodopa in the dosage form is 50 mg/200 mg with the carbidopa to levodopa amount in the immediate release portion being 25 mg/70 mg and the carbidopa to levodopa amount in the controlled release portion being 25 mg/130 mg. 24. A pharmaceutical dosage form according to claim 2, wherein said immediate release component is in the form of a coating on a solid dosage form; and said controlled release component makes up the solid dosage form, said controlled release component including a retarding agent of a type and amount sufficient to provide the release of active ingredient for a period of from about 1 hour to about 24 hours. 25. A method of treating a patient suffering from a pathology or diseases characterized by reduced levels of dopamine in a patients brain comprising the step of administering to the patient a dosage form according to any of claims 1, 2, 21 or 22. 26. The pharmaceutical dosage form according to claim 2 wherein the dosage form is a matrix dosage form. 27. The pharmaceutical dosage form according to claim 26 wherein the dosage form is a bilayer tablet. 28. The pharmaceutical dosage form according to claim 2 wherein the dosage form includes immediate release particles in combination with controlled release particles. 29. The pharmaceutical dosage form according to claim 28 wherein the immediate release particles and controlled release particles are within an immediate release gelatin capsule. 30. The pharmaceutical dosage form according to claim 28 wherein the immediate release particles and controlled release particles are in the form of a two-layer tablet. 31. The pharmaceutical dosage form according to claim 2 wherein the in vitro release rate is chosen such that the initial peak plasma level of levodopa obtained in vivo occurs between 0.1 and 2 hours after administration of the dosage form to a patient.