Claims for Patent: 8,795,725

Summary for Patent: 8,795,725

Title:	GABA analog prodrug sustained release oral dosage forms
Abstract:	Sustained release oral dosage forms of a gabapentin prodrug, 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid, are disclosed. The dosage forms are useful for treating or preventing diseases and disorders for which gabapentin is therapeutically effective.
Inventor(s):	Cundy; Kenneth C. (Redwood City, CA), Sastry; Srikonda (Sunnyvale, CA), Leung; Manshiu (Daily City, CA), Kadri; Balaji V. (Tampa, FL), Stach; Paul E. (Plymouth, MN)
Assignee:	XenoPort, Inc. (Santa Clara, CA)
Application Number:	11/269,045
Patent Claims:	1. A sustained release oral tablet comprising: (a) 40 wt % to 65 wt % of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid; (b) 1 wt % to 30 wt % of glyceryl behenate; and (c) 30 wt % to 50 wt % of dibasic calcium phosphate; wherein wt % is based on the total dry weight of the dosage form, which tablet: when administered to one or more fasted human patients at a dose of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid ranging from 1100 mg to 1300 mg provides a gabapentin plasma concentration profile characterized by a C.sub.max ranging from 3 .mu.g/mL to 6 .mu.g/mL, a T.sub.max ranging from 4 hours to 7 hours, and an AUC ranging from 30 .mu.ghr/mL to 70 .mu.ghr/mL; or when administered to one or more fed human patients at a dose of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid ranging from 1100 mg to 1300 mg provides a gabapentin plasma concentration profile characterized by a C.sub.max ranging from 5 .mu.g/mL to 8 .mu.g/mL, a T.sub.max ranging from 6 hours to 11 hours, and an AUC ranging from 60 .mu.ghr/mL to 110 .mu.ghr/mL. 2. The tablet of claim 1, which is compressed to a hardness of at least 15 kiloponds. 3. The tablet of claim 1, comprising an amount of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid ranging from 300 mg to 700 mg. 4. The tablet of claim 1, wherein the 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid is in a crystalline form. 5. The tablet of claim 1, comprising one or more pharmaceutically acceptable excipients selected from diluents, lubricants, anti-adherents, glidants, surfactants, disintegrants, and combinations of any of the foregoing. 6. The tablet of claim 5, wherein the diluent is microcrystalline cellulose. 7. The tablet of claim 1, wherein the tablet comprises 600 mg of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid, and the dose comprises two of the tablets. 8. The tablet of claim 1, comprising a coating. 9. The tablet of claim 1, which when administered to the one or more fasted human patients at a dose of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid ranging from 1100 mg to 1300 mg provides a gabapentin plasma concentration profile characterized by a C.sub.max ranging from 3 .mu.g/mL to 6 .mu.g/mL, a T.sub.max ranging from 4 hours to 7 hours, and an AUC ranging from 30 .mu.ghr/mL to 70 .mu.ghr/mL; and when administered to the one or more fed human patients at a dose of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid ranging from 1100 mg to 1300 mg provides a gabapentin plasma concentration profile characterized by a C.sub.max ranging from 5 .mu.g/mL to 8 .mu.g/mL, a T.sub.max ranging from 6 hours to 11 hours, and an AUC ranging from 60 .mu.ghr/mL to 110 .mu.ghr/mL. 10. The tablet of claim 1, which when administered to a population of said fasted human patients at a dose of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid ranging from a 1100 mg to 1300 mg provides a gabapentin plasma concentration profile characterized by a mean C.sub.max ranging from 3 .mu.g/mL to 6 .mu.g/mL, a mean T.sub.max ranging from 4 hours to 7 hours, and a mean AUC ranging from 30 .mu.ghr/mL to 70 .mu.ghr/mL; and when administered to a population of said fed human patients at a dose of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid ranging from 1100 mg to 1300 mg provides a gabapentin plasma concentration profile characterized by a mean C.sub.max ranging from 5 .mu.g/mL to 8 .mu.g/mL, a mean T.sub.max ranging from 6 hours to 11 hours, and a mean AUC ranging from 60 .mu.ghr/mL to 110 .mu.ghr/mL. 11. The tablet of claim 1, wherein: the one or more fasted human patients do not eat any food from 10 hours prior to administering the dose until 4 hours after dosing, drink 250 mL of water 2 hours and 1 hour prior to dosing and 250 mL of water a 2 hours after dosing, eat a lunch 4 hours after dosing, and eat a dinner 10 hours after dosing; and the one or more fed human patients begin eating a test meal 30 minutes prior to administering the dose and complete eating the test meal 5 minutes prior to administering the dose, eat a lunch 4 hours after dosing, and eat a dinner 10 hours after dosing, wherein the test meal comprises 1000 total calories of which 500 calories comprise fat calories. 12. A sustained release oral tablet comprising: (a) 40 wt % to 65 wt % of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid; (b) 1 wt % to 30 wt % of glyceryl behenate; and (c) 30 wt % to 50 wt % of dibasic calcium phosphate; wherein wt % is based on the total dry weight of the tablet, which tablet when placed in 10 mM monobasic potassium phosphate buffer and 1% (wt/volume) sodium lauryl sulfate at pH 7.4 and 37.degree. C. agitated at 50 rpm (USP, Type II), releases 20% of the 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid after 2 hours, 50% after 5 hours, and 80% after 8 hours. 13. The tablet of claim 12, comprising an amount of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid ranging from 500 mg to 700 mg. 14. The sustained release oral tablet according to claim 1, further comprising: 5 wt % to 20 wt % of microcrystalline cellulose. 15. The tablet of claim 14, comprising an amount of 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid ranging from 500 mg to 700 mg. 16. A sustained release oral tablet, comprising: 45.8 wt % 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid; 39.56 wt % dibasic calcium phosphate; 4.58 wt % glyceryl behenate; 6.11 wt % talc; 0.41 wt % colloidal silicon dioxide; 1.84 wt % sodium lauryl sulfate; and 1.69 wt % magnesium stearate; which tablet is optionally coated. 17. The tablet of claim 16, comprising 300 mg to 700 mg 1-{[(.alpha.-isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane acetic acid. 18. A method of treating restless legs syndrome, comprising administering a tablet according to one of claims 1, 12, or 16, to a patient in need of such treatment. 19. A method of treating post-herpetic neuralgia, comprising administering a tablet according to one of claims 1, 12, or 16, to a patient in need of such treatment.